Table of Contents
Section of Bioengineering
Department of Biomathematics
Section of Biostatistics
Staff
Stuart Zimmerman, Ph.D. (1964) University of Chicago
Chairman, Department of Biomathematics, Mattie Allen Fair Research Chair Professor of Biomathematics
Chief, Section of Biostatistics (ad interim)
Areas: Biomathematics; biomedical computing; image processing;
computer karyotyping; biostatistics; cell kinetics
Peter F. Thall, Ph.D. (1975) Florida State University
Associate Professor of Biomathematics
Areas: Clinical trial design; survival analysis; statistical modeling;
nonlinear regression; longitudinal and repeated measures data;
computer-intensive methods in statistics; applied Bayesian methods
Su-Chun Cheng, Sc.D. (1995) Harvard School of Public Health
Assistant Professor of Biomathematics
Areas: statistical methods for survival data; design and analysis
of clinical trials
Kenneth R. Hess, Ph.D. (1992) The University of Texas School of
Public Health
Assistant Professor of Biomathematics
Areas: Survival data analysis; tree-based statistical models;
statistical consulting; statistical education for medical researchers;
prognostic factor studies
J. Jack Lee, Ph.D. (1989) University of California at Los Angeles
Assistant Professor of Biomathematics
Areas: Biostatistics; survival data analysis; design and analysis
of clinical trials; longitudinal data analysis; statistical computing
and graphics
J. Lynn Palmer, Ph.D. (1988) The University of Texas School of
Public Health
Assistant Professor of Biomathematics
Areas: Biostatistics; design and analysis of clinical trials;
longitudinal data analysis; Bayesian methods of design and analysis
Yu Shen, Ph.D. (1994) The University of Washington School of Public
Health
Assistant Professor of Biomathematics
Areas: Design and analysis of clinical trials; survival analysis;
estimation of natural history of diseases
Terry L. Smith, M.S. (1986) The University of Texas School of
Public Health
Assistant Professor of Biomathematics
Areas: Design and analysis of clinical trials; evaluation of prognostic
factors and their use in treatment comparisons
Mary Ann Gregurich, Ph.D. (1993) The University of Texas School
of Public Health
Research Associate
Areas: Biostatistics; statistical consulting; survey analysis;
statistical computer program packages; Bayesian methodology
Hai-An Hsu, Ph.D. (1995) The University of Texas School of Public
Health
Programmer Analyst II
Areas: Clinical trials and survival analysis
Chris Schacherer, Ph.D. (1996) Rice University
Programmer Analyst II
Areas: Database management; user interface design; psychometric
analysis
Qiong Dong, M.S. (1993) Iowa State University
Programmer Analyst II
Areas: Clinical trials and survival data analysis
Hsi-Guang Sung, M.S. (1996) University of Washington
Programmer Analyst II
Areas: Statistical computing
Chi-Hong Tseng, M.S. (1994) Iowa State University
Programmer Analyst II
Areas: Data analysis and statistical genetics
Jesus Rodriguez, B.S. (1993) The University of Houston
Computer Programmer II
Areas: Database development and programming; data analysis; statistical
programming
Activities
To collaborate with staff members of other Departments on the
design, analysis, interpretation, and reporting of clinical, observational,
and laboratory studies in cancer research.
To perform research in biostatistics on methodological problems
arising in consulting.
To provide biostatistical consultation and resources, including
educational lectures to clinical research scientists engaged in
the planning, conduct, analysis, and interpretation of clinical
research studies.
- Skin Cancer Control. Dr. T. E. Moon.
Skin cancers are the most common neoplasms in the United States,
commonly classified as melanoma, basal cell carcinoma (BCC) and
squamous cell carcinoma (SCC). Over 700,000 new skin cancers are
projected to be diagnosed in 1995, equalling approximately 58%
of the number of all other types of cancers combined. Skin cancer
annual incidence has increased for at least the past two to three
decades, with melanoma incidence showing the second highest increase
of all types of cancer. Although the survival rate for melanoma
has increased, skin cancer represents an increasingly important
health and economic problem. Health implications resulting from
the increasing incidence of skin cancer in the U.S. are further
intensified by the continued population migration to sunnier,
more southern regions and by the reduced stratospheric ozone.
Thus, there is increasing need to better understand the etiology
and to control skin cancer. Surveillance of skin cancer incidence
for defined populations is essential to accurately calculate the
magnitude of the cancer burden and also provides an important
reference to evaluate cancer control interventions. Improved statistics
and adaptation of biostatistical methods are critical to the successful
use of surveillance data. A publication is in preparation on skin
cancer surveillance.
The retinoid skin cancer prevention clinical trials have been
completed. These trials tested the hypothesis that vitamin A and
its synthetic derivatives (retinoids) reduce the risk of skin
cancers (SCC or BCC) in high risk individuals. Over 3,500 individuals
participated in these two complementary vitamin A clinical trials.
By use of more contemporary biostatistical methods (CART and other
regression models), the value of vitamin A supplementation will
be determined and the specific subgroup of individuals that benefitted
from retinoids identified. These results will not only benefit
the control of skin cancer but also common cancer types (squamous
cell type) that arise in other parts of the body. One publication
has been submitted and three other publications are in preparation.
- Evaluation Of Cancer Biomarkers. Dr. T.E. Moon, Dr.
R. Lotan, Dr. T.C. Shu, and Dr. H.N. Ananthaswamy.
The evaluation of biologic (bio) markers of carcinogenesis is
continuing to determine how to identify individuals at high risk
of cancer, biologic explanations of their high risk, and how to
cost effectively select interventions to control cancer. The success
of molecular biology research has resulted in the description
of an increasing number of putative biomarkers. Combined with
established clinical, medical and environmental risk factors,
the clinical value of such biomarkers requires adapting and developing
biostatistical methods. Also, the influence of measurement error
and heterogeneity of study subjects is included in the evaluation.
A population based case control study of all three major types
of skin cancer has been completed and provides data on multiple
risk factors and putative biomarkers, including dietary intake,
blood micro and macro nutrients, tissue fatty acid profiles plus
exposure and susceptibility measures. Data analyses indicate a
substantial variation in skin cancer risks by ultraviolet light
exposure and skin pigmentation. Unfortunately, these two risk
factors are of modest value in predicting who will develop skin
cancer. Various statistical techniques are being evaluated to
determine cost effective ways of integrating biomarkers into the
design of new clinical studies. A publication is in preparation
on the evaluation of biomarkers and other risk factors for the
three different types of skin cancer.
- Egyptian Cancer Research and Education Programs. Dr.
T. Moon, Dr. A. Soliman, Dr. M. Shebl, and Dr. K. El-Beltagy.
Our activities in Egypt focus on epidemiologic research for identifying
the risk factors and biomarkers of skin and liver cancer. Other
projects include developing a teaching curriculum for cancer control
and prevention and improving faculty skills in epidemiology and
biostatistics through a series of teaching workshops, coupled
with training Egyptian junior faculty at The University of Texas
M.D. Anderson Cancer Center.
- Time Dependence of Prognostic Effects.
Dr. K. Hess.
In a typical analysis of time-to-event data, covariates are assumed
to have a constant effect over the entire follow-up period. However,
some covariates violate this so-called proportional hazards assumption
by having effects which vary over time. For example, some covariates
are good predictors of short-term survival but poor predictors
of long-term survival. Methods were reviewed and some new methods
developed for identifying the presence and nature of the time
dependence and for modelling the time dependence of the covariate
effects. Alternative methods for demonstrating the presence of
time-dependent covariate effects were also pursued.
A powerful and straightforward method is to partition the follow-up
time into mutually exclusive intervals and then to compute survival
curves and relative risks within each interval. Plotting the relative
risks against the interval midpoints can be helpful in assessing
time-dependence. Instead of viewing the relative risk as a step
function of time, we can model it as a continuous function of
time. A convenient method is to use an extended Cox regression
model which incorporates a time-by-covariate interaction term
modelled as a product between the covariate and a function of
time. Smoothed plots of the Grambsch-Therneau-Schoenfeld residuals
are indispensable in deciding the correct function of time to
use. It is possible to fit simple transformations of time, polynomial
functions of time, and even piecewise polynomials of spline functions
of time (Recent Publications, #34
and #35).
- Metastatic Patterns. Dr. J. Abbruzzese and Dr. K. Hess.
The goals of this study are to describe and analyze the patterns
of metastases for a cohort of patients with single primary tumors
and to determine the feasibility of predicting the location of
the primary based on the pattern of metastases and certain clinical
and demographic factors. Patients admitted to UTMDACC during 1992
with one or more metastases and a single primary were identified
through the Patient Studies' EPIMAST database. Data on age, race,
sex, histology and metastatic pattern were acquired for 2,903
adult patients with one of the 13 primaries and one of the four
major histologic categories of interest. Preliminary analyses
using linear discriminant analysis and classification tree analysis
were performed on (1) women with colon, lung, breast and ovary
primaries and (2) men with buccal, colon, lung and prostate primaries.
The primary location was correctly predicted in 85% to 90% of
patients. Ultimately, the results will be compared to data from
the Unknown Primary Clinic to assess our ability to predict the
location of primaries in patients in whom the primary could not
be found clinically.
- A Better Confidence Interval for Kappa on
Measuring Agreement Between Two Raters with Binary Outcomes
(Recent Publications, #43).
Dr. J. Lee and Ms. Z. N. Tu.
Although the kappa statistic is widely used in measuring interrater
agreement, it is known that the standard confidence interval estimation
behaves poorly in small samples and for nonzero kappas. Efforts
have been made to improve the estimation through transformation
and Edgeworth expansion. However, the results remain unsatisfactory
when kappa is far from 0, even with the sample size as large as
100. In this research, we reparameterize the kappa statistic to
reveal its relationship with the marginal probability of agreement.
The reparameterization not only gives a more meaningful interpretation
of kappa but also clearly demonstrates that the range of kappa
depends on the marginal probabilities. Various 2-D and 3-D plots
are shown to illustrate the relationship among these parameters.
The immediate application is to construct a new confidence interval
based on the profile variance and reparameterization. Extensive
simulation studies show that the new confidence interval performs
very well in almost all parameter settings even when other methods
fail.
- Likelihood-Weighted Confidence Intervals for the Difference
of Two Binomial Probabilities. Dr. J. Lee, Dr. B.W. Brown,
and Mr. D.M. Serachitopol.
Two new methods for computing a confidence interval for the difference
of two binomial proportions are proposed. Both methods are based
on a weighted likelihood approach which maps the tail probabilities
in the two-dimensional space into a function of the one-dimensional
difference so that the weighted tail probability is
/2
at each end. The probability computation is based on the exact
distribution rather than the large sample approximation. This
procedure may be regarded as a natural extension of the Clopper
and Pearson (Biometrika, 26:404-413, 1934) interval to
the two-sample case. An extensive computation study was carried
out to evaluate the coverage probability and width of the likelihood
weighted intervals, and compared them to several other methods
reported in the literature. The likelihood weighted intervals
compare very favorably with the standard asymptotic interval and
with intervals proposed by Hauck and Anderson (The American
Statistician, 40:318-322, 1986); Cox and Snell (Analysis
of Binary Data, 2nd ed., Chapman and Hall: New York, 1989);
Santer and Snell (Journal of the American Statistician, 75:386-394,
1980); Santer and Yamagami (Communication in Statistics, 18:1325-1341,
1993); and Peskun (Journal of the American Statistical Association,
88:656-661, 1994). In particular, the likelihood weighted
intervals provide the best balance between accurate coverage probability
and short interval width.
- A Versatile One-Dimensional Distribution Plot: The BLiP
Plot. Dr. J. Lee and Ms. Z. N. Tu.
A versatile graphical tool, the BLiP plot, was developed
for displaying one-dimensional data. The basic building blocks
are boxes, lines, and points. Similar
to many standard one-dimensional distribution plots, the BLiP
plot is capable of displaying individual data value in points
or lines and grouped information in lines or boxes. In addition,
the BLiP plot includes many useful new features such as
variable-width plots. The central idea of the BLiP plot
is to provide basic graphical elements in a friendly and flexible
environment so that users can construct anything from a simple,
standard plots to a complex, customized plot to best present their
data. The program is available in the S functional form
and may be utilized on many computer platforms.
- Statistical Analysis of the Reliability and Classification
Error of the Mutagen Sensitivity Assay. Dr. J. Lee, Dr. Z.
Trizna, Dr. T. C. Hsu, and Dr. W. K. Hong.
Statistical analysis was applied to evaluate the reliability and
classification errors of the in vitro bleomycin sensitivity
assay(BSA). It has been demonstrated that BSA can be used for
determining an individual's genetic susceptibility to cancer.
The standard practice is to read 50 metaphases in each sample
and compute the mean chromatid breaks per cell (b/c). Since scoring
breaks is a time-consuming task, various fixed number and variable
number designs were evaluated to establish efficient and reliable
reading strategies. A collection of 160 cases with 100 consecutive
readings for each case was obtained. The b/c values were between
0.14 and 1.30 (mean: 0.61). Standard errors(SE) based on scoring
50 and 100 metaphases were 0.15 and 0.11, respectively. After
evaluating the first 50 metaphases, the gain in reducing SE is
less than 1% with each additional reading. Comparing to 100 readings,
the misclassification error for scoring 50 metaphases is less
than 4% but the maximum bias can be as high as 0.35. Variable
number designs reduce the bias of the fixed number design by reading
additional metaphases until the estimated SE is within a prespecified
bound. The maximum bias is reduced to 0.13 when SE<0.15. Reading
50 metaphases is sufficiently accurate for bleomycin-resistant(b/c<1.0)
subjects, while the variable number design should be applied to
increase the reliability for bleomycin-sensitive (b/c
1.0) subjects. Efficient and reliable scoring
methods can be applied in large scale cancer epidemiology studies
for individual risk assessment.
- Nonparametric Analysis of Longitudinal Data. Dr. J.
G. Staniswalis and Dr. J. Lee.
Methods were developed for analyzing data involving repeated measures
of the outcome variable in multiple groups over irregular time
intervals. It is demonstrated that the functional form of the
response curve can be recovered through nonparametric and semiparametric
modeling. The group effect, time effect, and group x time interaction
can be estimated and tested. Practical considerations such as
bandwidth selection in nonparametric smoothing, model robustness
to outliers, estimation accuracy in terms of sample size and signal-noise
ratio were also studied. The strength and limitation of this approach
will be compared to other methods reported in the literature,
such as the Laird-Ware model and GEE methods.
- Repeated Confidence Intervals and Bayesian Implementation
of Equivalence Trials. Dr. J. Lee and Mr. J.A. Dubin.
"Proving the null hypothesis" approach in equivalence
trials (Blackwelder, Controlled Clinical Trials, 3:345-353,
1982) is not suitable for interim analysis in the group sequential
setting because trials cannot be stopped early when the experimental
treatment is much worse than the standard. More appropriate methods
were proposed by constructing the repeated confidence intervals
(Durrleman and Simon, Biometrics, 46:329-336, 1990; Jennison
and Turnbull, Biometrics, 49:31-43, 1993). An alternative
is applying the Bayesian method for interim monitoring of equivalence
trials by adding the "handicap" proportion (Grossman,
et al., Statistics in Medicine, 13:1815-1826, 1994). The performance
of various repeated confidence methods and the Bayesian methods
were compared in simulation studies. It was found that while all
methods preserve the overall significance level, the Bayesian
approach is more efficient. As the number of tests increases,
the averaged sample size decreases for all methods. However, the
power decreases for repeated confidence intervals but increases
for the Bayesian method. The Bayesian method is also robust among
several choices of non-informative priors. Confidence interval
approaches and the Bayesian method offer more specific conclusions
(equivalent, non-equivalent, or inconclusive) compared to the
standard hypothesis testing method. They can also be easily adapted
to the group sequential designs to reduce the averaged sample
size.
- Bayesian Optimal Design in Population Models of Hematologic
Data. Dr. J.L. Palmer, Dr. M. Korbling, Dr. R.E. Champlin,
and Dr. P. Müller.
A population model was designed to investigate an optimum apheresis
schedule for breast cancer patients. Blood stem cells are collected
by apheresis prior to the patient's undergoing high-dose chemoradiotherapy
and these cells are returned after treatment to enable reconstitution
of white blood cells. Maximizing the number of blood stem cells
collected in as few aphereses as possible is desirable. We use
a longitudinal data model with random effects to describe profiles
of individual patients. A hierarchical prior model introduces
common mean profiles for patients undergoing different treatments.
The optimal apheresis schedule for a new patient is found by minimizing
an expected loss over the posterior predictive distribution of
the patient's predicted CD34 profile. Estimation of the model
and solution of the optimal design problem are implemented by
a simulation approach, which allows us to accommodate arbitrary
shapes for the profiles and realistic loss functions which include
relative penalties for the number of scheduled stem cell collections
and for collecting fewer than a specified target quantity of total
collected stem cells.
- Bayesian Estimates of Autocorrelation in
a Regression Model. Dr. J.L. Palmer, Dr. L.D. Broemeling,
and Dr. L.I. Pettit.
Two Bayesian estimates of autocorrelation were derived assuming
the errors of a multiple linear regression model follow a first
order autoregressive process. The first estimate is based on the
conditional posterior distribution of the autocorrelation parameter,
, given the regression
coefficients. A test of this estimate can be made by conditioning
on the usual least-squares estimate of the regression parameters
and constructing a region of highest posterior density (HPD).
The resulting t-test is convenient and easily implemented using
standard software packages. The second estimate is based on marginal
posterior distributions of regression and autocorrelation parameters
determined by a Gibbs sampling approach. For both estimates, posterior
inferences for estimation and testing have been made, with emphasis
on testing for no autocorrelation in the errors. Simulation results
show effects of sample size, values of the autocorrelation parameter,
and other sampling properties of the estimates of autocorrelation
(Recent Publications, #60).
Difficulty may be experienced when using the Gibbs sampler to
estimate the autocorrelation coefficient in a linear regression
model when moderate-to-high positive autocorrelated errors are
present. Although no problems in estimation were found, when the
true autocorrelation was near -1 estimates became unstable and
sometimes failed to converge when the true autocorrelation was
greater than 0.5. In order to determine the cause of this problem,
we simulated data with a positive autocorrelation of 0.9 and,
at each iteration of the Gibbs sampling process, recorded and
later evaluated estimates of
,
ß, and ß1. Results suggest that these estimation
difficulties are resolved when a vague but proper prior is used
rather than a non-informative, improper prior (Recent Publications,
#61).
- Strategies for Planning and Conducting Phase I Clinical
Trials of Chemotherapeutic Agents. Mrs. T. Smith, Dr. J.J.
Lee, Dr. M. Raber, and Mr. D. Serachitopol.
The objective of most Phase I trials of chemotherapeutic agents
is to establish a maximum tolerated dose of the agent which can
then be tested for anti-tumor efficacy in subsequent trials. The
usual approach is to administer increasing dose levels to small
cohorts of patients until some acceptable level of toxicity is
exceeded. Recent proposals in the statistical literature for more
quantitative methods of dose determination include a "continual
reassessment ethod" in which toxicity outcomes associated
with all previous patient doses are used to update a dose-response
model and decide the dose for an incoming patient. In a survey
of Phase I trials conducted recently at MDACC, it was learned
that all were conducted by conventional methods. Trials fell into
distinct categories, classified, for example, by whether or not
a trial represented the first administration of an agent in humans.
Information from this survey will be used to propose practical
alternatives to the continual reassessment and other methods,
and computer programs already developed to implement these methods
will be appropriately modified. Discussions are ongoing with clinicians
regarding suitable trials in which some of these methods can be
implemented.
- Uses of Prognostic Factors in the Planning and Analysis
of Clinical Studies. Mrs. T. Smith.
Since heterogeneity among patients with respect to prognostic
factors often leads to more variability in outcomes than is dependent
upon the particular therapy administered, it is of great importance
to account properly for the prognostic features of the patients.
Knowledge of prognostic factors is essential for both the design
and analysis of clinical trials, and also in evaluating clinical
importance of the many new biological parameters which can now
be measured in laboratory investigations. Application of standard
methods such as proportional hazards regression analysis in the
case of survival-type endpoints often leads to impressive relative
risk estimates and highly significant P-values for certain factors.
Additional analyses which yield estimates of the amount of variation
in an outcome variable explained by those factors may provide
the clinical investigator a more realistic understanding of the
disease being studied. Various aspects of these problems are under
investigation in clinical studies, e.g. in leukemia, prostate
cancer, breast cancer, lymphoma, head and neck cancer.
- Evaluation of the Adequacy of Follow-up Time Available
in Investigations Involving a Survival-Type Endpoint. Mrs.
T. Smith and Dr. M. Schemper.
Much clinical research is based on the comparison of survival-
type endpoints to draw conclusions regarding treatments, prognostic
factors, or disease course. In designing randomized trials, a
minimum amount of follow-up duration must be specified and adhered
to in order to achieve the required power for the hypothesis being
tested. Studies of prognostic factors are usually not prospectively
designed, and may be based on a cohort of patients drawn from
various sources and with no specified follow-up requirements.
In such studies, there may be some unmeasured influence determining
which patients are followed more completely. Various methods are
used to describe the amount of follow-up when studies comparing
survival are reported in the clinical literature, and some reports
do not address the issue of follow-up at all. The value of the
various methods for determining duration of follow-up when not
all cases have been followed to completion (i.e. censored) is
being investigated, with the intent to make recommendations for
more meaningful summaries of available follow-up.
- A Bayesian Strategy for Screening Cancer
Treatments Prior to Phase II Clinical Evaluation (Recent
Publications, #79).
Dr. P. Thall and Dr. E. Estey.
We address the problem of selecting a treatment for phase II evaluation
when several candidate treatments emerging from phase I testing
are available. A pre-phase II Bayesian selection design which
randomizes patients among treatments is proposed. The patient
group in the trials has a prognosis more favorable than that of
phase I patients but less favorable than the target group of the
subsequent phase II trial. The patient response rate distribution
in each treatment arm is continually updated during the trial
for comparison with early termination cutoffs, and the best final
treatment must satisfy a minimal posterior efficacy criterion.
The primary aim is to replace the usual informal treatment selection
process with a fair comparison formally based on a combination
of prior opinion and clinical data.
- New Designs for the Selection of Treatments
to be Tested in Randomized Clinical Trials (Recent Publications,
#73). Dr. R. Simon,
Dr. P. Thall, and Dr. S. Ellenberg.
The most important aspect of phase III randomized clinical trials
is the selection of the experimental treatments to be tested.
Often this decision is based on uncontrolled phase II trials.
Substantial statistical attention has been focused on the design
of phase III trials. Much less statistical effort has been devoted
to the design and analysis of phase II trials for screening effective
experimental treatments to determine whether they are sufficiently
effective, relative to standard treatments, to warrant the conduct
of a large randomized phase III trial. This problem is particularly
acute in the development of drug combinations where many regimens
are possible. We review several designs for such screening trials
which we have developed.
- Practical Bayesian Guidelines for Phase
IIB Clinical Trials (Recent Publications, #82).
Dr. P. Thall and Dr. R. Simon.
A phase IIB clinical trial typically is a single arm study aimed
at deciding whether a new treatment E is sufficiently promising,
relative to a standard therapy S, to include in a large-scale
randomized trial. Thus, phase IIB trials are inherently comparative
even though a standard therapy arm usually is not included. Uncertainty
regarding the response
of S is rarely made explicit, either in planning the trial
or interpreting its results. We propose practical Bayesian guidelines
for deciding whether E is promising relative to S
in settings where patient response is binary and the data are
monitored continuously. The design requires specification of an
informative prior for
,
a targeted improvement for E and bounds on the allowed
sample size. No explicit specification of a loss function is required.
Sampling continues until E is shown to be either promising
or not promising relative to S with high posterior probability,
or the maximum sample size is reached. The design provides decision
boundaries, a probability distribution for the sample size at
termination, and early stopping probabilities under fixed response
probabilities with E.
- An Optimal Three-Stage Design for Phase
II Clinical Trials (Recent Publications, #23.
Ms. L. Ensign, Dr. E.A. Gehan, Mr. D.S. Kamen, and Dr. P.F. Thall.
A phase II clinical trial in cancer therapeutics is usually a
single-arm study to determine whether an experimental treatment
(E) is sufficiently promising to warrant further testing,
usually in a much larger randomized comparative trial. Patient
response is generally defined as a binary variable denoting treatment
success/failure, with the parameter p = Pr (success) the
criterion for evaluating treatment efficacy. The design for two-stage
phase II cancer clinical trials proposed by Gehan (1961) provided
the minimum number of patients required so that if all patients
were non-responders, further study of the therapy could be discontinued
with a given type II rejection error.
Simon (1989) considered two-stage procedures that permitted rejection
of a therapy at either of two stages, but acceptance only at the
final stage. The rationale was that stopping a study early was
undesirable when a therapy appeared to be effective, but desirable
when the treatment seemed ineffective. Simon's design was optimal
in that it minimized null expected sample size at given levels
of significance and power. One drawback to Simon's design is that
it does not allow early termination if there is a long run of
failures at the start.
We propose a three-stage design that permits early stopping when
a moderately long sequence of initial failures occurs. In Stage
1, n1 patients are treated and the trial terminates
if all n1 are treatment failures. If one or
more successes are observed in Stage 1, then Stage 2 and (possibly)
Stage 3 are implemented, the latter two stages having the same
decision rule structure as in Simon's Stages 1 and 2. The optimal
three-stage design is parameterized to minimize the null expected
sample size.
- A Bayesian Approach to Establishing Sample
Size and Monitoring Criteria for Phase II Clinical Trials
(Recent Publications, #81).
Dr. P. Thall and Dr. R. Simon.
Thall and Simon propose
a Bayesian approach to phase II clinical trials with binary outcomes
and continuous monitoring. The efficacy
of an experimental treatment E is evaluated relative to
that of a standard treatment S based on data from an uncontrolled
trial of E, an informative prior for
and a non-informative prior for
.
The trial continues until Eis shown with high posterior
probability to be either promising or not promising, or until
a predetermined maximum sample size is reached. Operating characteristics
are evaluated under fixed values of the success probability of
E.
We propose two extensions of this decision structure, describe
sample size and monitoring criteria, and provide numerical guidelines
for implementation. The first extension gives criteria for early
termination of trials unlikely to yield conclusive results, based
on the marginal (predictive) distribution of the observed
success rate. The second extension allows early termination only
if E is found to be not promising compared to S.
Operating characteristics of each of these designs are evaluated
numerically over a range of design parameterizations. We also
examine the effects of intermittent monitoring on the design's
properties. An application of this approach to a leukemia bio-chemotherapy
trial is described.
- Bayesian Sequential Monitoring Designs
for Single-Arm Clinical Trials with Multiple Outcomes (Recent
Publications, #84).
Dr. P. Thall, Dr. R. Simon, and Dr. E. Estey.
We present a Bayesian approach for monitoring multiple outcomes
in single-arm clinical trials. Each patient's response may include
both adverse events and efficacy outcomes, possibly occurring
at different study times. We use a Dirichlet-multinomial model
to accommodate general discrete multivariate response. We present
Bayesian decision criteria and monitoring boundaries for early
termination of studies with unacceptably high rates of adverse
outcomes or low rates of desirable outcomes. Each stopping rule
is constructed either to maintain equivalence or to achieve a
specified level of improvement of a particular event rate for
the experimental treatment, compared with standard therapy. We
avoid specification of costs and a loss function. We evaluate
the joint behavior of the multiple decision rules using frequentist
criteria. Applications include trials where response is the cross-product
of multiple simultaneous binary outcomes, and hierarchical structures
that reflect successive stages of treatment response, disease
progression and survival. We illustrate the approach with a variety
of single-arm cancer trials, including bio-chemotherapy acute
leukemia trials, bone marrow transplantation trials, and an anti-infection
trial, with up to seven elementary patient outcomes in each, and
up to four monitoring boundaries running simultaneously. We provide
general guidelines for eliciting and parameterizing Dirichlet
priors and for specifying design parameters.
- Recent Developments in the Design of Phase
II Clinical Trials (Recent Publications, #83).
Dr. P. Thall and Dr. R. Simon.
This article reviews statistical methods for the design and conduct
of phase II clinical trials. Following a description of the basic
phase I-II-III paradigm, the single-stage phase II trial design
is described in detail. The limitations of this design are discussed,
and more general approaches to treatment development are described.
These approaches include designs for selecting treatments prior
to phase II, randomized phase II trials, conduct of a sequence
of phase II trials, and an integrated phase II/III approach. Practical
considerations in the design and conduct of phase II trials are
discussed, followed by descriptions of specific designs which
incorporate historical data, Bayesian designs, designs with early
stopping rules, and designs which account for multiple patient
outcomes.
- Analysis of CD7 Expression in Acute Myelogenous
Leukemia: Martingale Residual Plots Combined with "Optimal"
Cutpoint Analysis Reveals Absence of Prognostic Significance
(Submitted Publications, #10).
Dr. S.M. Kornblau, Dr. P.F. Thall, Dr. Y.O. Huh, Dr. E.H. Estey,
and Dr. M. Andreeff.
Conflicting results regarding the prognostic significance of CD7
expression in acute myelogenous leukemia (AML) have appeared in
the literature. Differences in the method for determining CD7
positivity, the antibody used, the therapy administered, and the
CD7 level used as a cutoff for reducing it to a binary variable
all have been postulated to account for the discordant findings.
In this study, CD7 level was determined by flow cytometry in 331
patients with newly diagnosed AML. Martingale residual plots from
fitted Cox regression models of survival on CD7 and an exhaustive
cutpoint search were used to obtain "optimal" cutpoints
for determining whether a patient was CD7 positive or negative.
After accounting for cytogenetic category and other important
prognostic variables (age, performance status, albumin), CD7 was
shown to have no additional prognostic value, either in its raw
numerical form or as a binary variable.
- Estimating Genomic Category Probabilities
from Fluorescent in situ Hybridization Counts With Misclassification.
(Recent Publications, #80
and Recent Publications, Section of Mathematical Biology,
#36). Dr. P.F. Thall,
Mr. D. Jacoby, and Dr. S.O. Zimmerman.
Fluorescent in situ hybridizating (FISH) is used in many
medical settings to identify the specific genetic alteration or
chromosomal abnormality characterizing a disease. Using FISH techniques,
a sample of a patient's cells may be classified into genomic categories,
one or more of which is associated with the disease. Estimating
the proportion of cells of a particular type based on count data
is complicated by classification error inherent in FISH methodology.
We address the problem of estimating the proportions of cells
of each category in the patient when background counts on cells
of known type are available. We do this by modelling the misclassification
probabilities and then estimating the parameters of the model
and the patient's cell-type proportions jointly using maximum
likelihood. Our objective is to obtain more reliable estimates
by accounting formally for misclassification error. The method
is applied to data arising in chronic myelogenous leukemia (CML),
where FISH is used to identify the translocation between chromosomes
9 and 22 which characterizes CML.
- Large Sample Properties of Some Survival
Estimators in Heterogeneous Samples. (Recent Publications,
#68). Dr. Y. Shen
and Dr. T. R. Fleming.
In studies having right-censored failure time data, the Kaplan-Meier
estimator is often used to estimate the corresponding survival
distribution. However, the Kaplan-Meier estimator can be biased
for a heterogeneous sample, in particular, when the censoring
mechanism is dependent on the survival mechanism. We investigated
a mean survival estimator that incorporates important covariates
associated with survival. The estimator is constructed based on
Cox's regression model and a weighting according to any specified
distribution of the baseline covariates. A mean hazard function
estimator is also derived corresponding to the multiplicative
intensity model which allows for recurrent outcome events.
- Weighted mean survival test statistics:
a class of distance tests for censored survival data (Recent
Publications, #69,
#70). Dr. Y. Shen
and Dr. T. R. Fleming.
A class of test statistics is introduced which is sensitive against
the alternative of stochastic ordering in the two-sample censored
data problem. The test statistics for evaluating a cumulative
weighted difference in survival distributions are developed while
taking into account the imbalances in baseline covariates between
two groups. This procedure can be used to test the null hypothesis
of no treatment effect, especially when baseline hazards cross
and prognostic covariates need to be adjusted. The statistics
are semiparametric, not rank based, and can be written as integrated
weighted differences in estimated survival functions, where these
survival estimates are adjusted for covariate imbalances.
- Estimating Asymptomatic Duration in Cancer:
The AIDS Connection . (Recent Publications, #25).
Dr. R. Etzioni and Dr. Y. Shen.
Many chronic diseases, including cancer and AIDS, do not manifest
themselves clinically until some time after their inception. In
studies of diseases' natural history, the duration of the asymptomatic
period is of interest -- in AIDS, to predict the epidemic's course,
and in cancer, to develop efficient screening strategies. By adapting
AIDS methodology to cancer, the article identifies a non-parametric
method for estimating the duration of the asymptomatic period
in cancer. The method is designed to be applied to data from a
cohort of individuals, screened periodically. The adapted EM algorithm
which, at convergence, provably yields a maximum or saddle point
of the likelihood. We investigate the performance of the algorithm
by means of a simulation study, and explore the effect of adding
a smoothing step to the estimation procedure.
- Parametric Likelihoods for Multiple Non-Fatal
Competing Risks and Death. (Submitted Publications,
#24). Dr. Y. Shen
and Dr. P.F. Thall.
Clinical trials of fatal diseases often focus on one or more non-fatal
events, in addition to survival, both to characterize morbidity
and to improve survival estimates. The statistical complications
are that the time to each non-fatal event and subsequent residual
survival may be either positively or negatively associated, the
times to death with or without an antecedent event often have
very different distributions, and death may censor some of the
non-fatal event times. Consequently, the overall survival time
distribution is a mixture of the distributions corresponding to
the possible antecedent non-fatal events. In this paper, we consider
a general parametric model for multiple non-fatal competing risks
and death. The model accounts for positive or negative association
between the time of each non-fatal event and subsequent survival
while accommodating covariates and the usual administrative censoring.
Each event time distribution is specified marginally, and the
time of each non-fatal event and subsequent residual survival
are combined under a bivariate generalized Morgenstern distribution.
The approach is illustrated by application to two data sets from
clinical trials in colon cancer and acute leukemia.
- Inference for Long Term Survival by Incorporating
Historical Control Information. (Submitted Publications,
#23). Dr. Y. Shen
and Dr. T.R. Fleming.
In this article, we present an approach to using historical control
data to augment information from a randomized controlled clinical
trial, when the clinical trial does not provide long term follow-up
for the control regimen. Based on an adjustment procedure to the
historical control data, estimation of the long term survival
function for the clinical trial control group and inference for
the long term treatment effect are obtained. Advantages of this
approach are its simple interpretation, validity in important
settings, and ability to be readily implemented using existing
software. Data from the first and second National Wilms' Tumor
studies are used to illustrate the method.
- Age Specific PSA: A Re-assessment.
(Submitted Publications, #6)
Dr. R. Etzioni, Dr. Y. Shen, Dr. J.C. Petteway and Dr. M.K. Brawer
Prostate specific antigen (PSA) has emerged as the most useful
of all serum tumor markers in prostate oncology. In this article,
we have attempted to compare the expected survival advantage when
screening for prostate cancer when a positive screen is defined
as PSA>4.0 ng/ml, with that expected when a positive screen
is defined as PSA greater than an age-specific bound. By extensive
statistical simulations, we found that using a bound of 4.0 ng/ml
for all ages is more efficient in identifying men with cancer
in a screening cohort and will ultimately provide increased population
longevity.
- Analysis of Failure Time Data with Linear
Transformation Models. (Recent Publications, #14
& #15) Dr. S.C.
Cheng, Dr. L.J. Wei and Dr. Z. Ying
In many clinical trials the goals are to evaluate the effects
of patient covariates on survival or disease progression time,
and to predict survival probabilities for future patients with
given characteristics. Statistical inference is complicated by
the presence of right censoring, due to the facts that some patients
are lost to follow-up, while others are still alive or have not
suffered disease progression or death at the end of the study.
For this common data structure, namely censored time-to-event
outcomes with covariates, the proportional hazards model introduced
by Cox (1972) is often used. The Cox model may not fit the data
well, however, when the proportional hazards assumption is not
met.
In this research we consider a large class of semi-parametric
transformation models, under which an unknown transformation of
the survival time is linear related to the covariates with various
specified error distributions. This class of regression models
includes the proportional hazards and proportional odds models.
Inference procedures, which are derived from a class of generalized
estimating equations, are proposed to examine the covariate effects
and to predict survival probabilities for future patients. These
methods provide a more general and practical alternative to the
Cox regression model.
- Distribution-Free Confidence Intervals
for Pr(X < Y) Based on Censored Survival Data. (Submitted
Publications, #5)
Dr. S.C. Cheng and Dr. P.F. Thall
In randomized clinical trials the primary goal is to compare the
efficacy of two treatments in terms of patient survival or disease
progression time. If X and Y denote the respective progression/survival
times of a random patient under the two treatments, treatment
comparison may be carried out by constructing a confidence interval
for Pr(X < Y). This quantifies the degree of superiority of
one treatment over the other and conveys more information than
a p-value. Cox's proportional hazards model (1972) provides a
semiparametric basis for estimating Pr(X < Y) based censored
survival data. Cheng, Wei and Ying (1995) can also be used to
derive semiparametric confidence interval for Pr(X < Y) under
an extension of the Cox model.
In this project we propose a robust nonparametric confidence interval
for Pr(X < Y) based on two independent samples of censored
survival data. Our procedure generalizes the nonparametric confidence
interval proposed by Mee (1990), which only accommodates the uncensored
case. Mee's procedure is a modification and improvement of the
method of Halperin, Gilbert and Lachin (1987), who in turn rely
on the approach used by Ghosh (1979) to construct a confidence
interval for a binomial parameter in the one sample case. We study
the nonparametric confidence interval by simulation under a range
of distributions having proportional hazards, proportional odds,
and neither of these properties, and under both moderate and heavy
censoring.
Our simulation results indicate that, in terms of closeness to
nominal coverage, the nonparametric interval is superior to the
Cox model-based interval under departures from proportional hazards,
and is superior to the semiparametric procedure of Cheng, Wei
and Ying (1995) for small to moderate sample sizes under heavy
censoring.
- Prediction of Cumulative Incidence Function
under the Proportional Hazards Model. (Submitted Publications,
#4) Dr. S.C. Cheng,
Dr. J.P. Fine and Dr. L.J. Wei
In the presence of dependent competing risks in survival analysis,
the Cox model can be utilized to examine the covariate effects
on the cause-specific hazard function for the failure type of
interest. For example, competing risks can be different causes
of death, or local recurrence versus recurrence involving a distant
metastasis. In this situation, the cumulative incidence function
provides an intuitively appealing summary curve for marginal probabilities
of the interested event.
In this project we show how to construct confidence intervals
and bands for such a function under the Cox model for future patients
with given covariates. Our proposals are illustrated with data
from two breast cancer studies conducted at M.D. Anderson Cancer
Center.
- Survival Analysis with Linear Transformation Models When
Covariate Variables are Measured with Error. Dr. S.C. Cheng,
Dr. N. Wang and Dr. L.J. Wei
In many biomedical studies, patient covariates are often measured
with error, or may not be directly observable. For analysis of
survival data, a naive and quite common approach to this problem
is to use the Cox model with the observed value of the covariates.
Unfortunately, this usually produces biased parameter estimates
and unreliable inferences. Existing statistical methods for censored
survival data accommodating covariates subject to measurement
errors have focused on the estimation of the parameters in the
Cox model. In this project we will explore the effect of covariate
measurement error on the estimation of regression parameters as
well as the prediction of survival probabilities in the context
of a much more general class of models.
- Two-Stage Selection and Testing Designs for Clinical Trials
Monitoring Both Safety and Efficacy Outcomes. Dr. P.F. Thall
and Dr. S.C. Cheng
This project addresses the general problem of evaluating several
new "experimental" treatments and comparing them to
an established "standard" treatment. In particular,
it is highly desirable to determine which, if any, of the experimental
treatments are promising compared to the standard as quickly but
reliably as possible, due to limited resources. Thall, Simon,
and Ellenberg (1988, 1989) developed optimal two-stage phase II/III
designs which first select the best experimental treatment and,
if it is promising, subsequently compare it to the standard in
a larger second stage. These designs are limited to trials with
a single, binary "success" outcome, hence do not accommodate
safety monitoring. We propose to develop optimal two-stage selection
and testing designs which deal with bivariate patient responses,
including both adverse and efficacy outcomes. These outcomes are
similar to those treated by the Bayesian continuous-monitoring
design of Thall, Simon, and Estey (1996). Additionally, decision
rules will be based on a two-dimensional representation of clinically
meaningful trade-offs between safety and efficacy.
- A Bayesian Analysis for Estimating the
Common Mean of Independent Normal Populations using the Gibbs
Sampler. (Recent Publications, #29)
Dr. Mary Ann Gregurich and Dr. Lyle D. Broemeling.
Combining information from several independent normal populations
to estimate a common parameter has applications in meta-analysis
and is an important statistical problem. For this application,
a Bayesian technique via the Gibbs sampler is adopted. Given several
normal independent populations with a common mean and different
variances, it is possible to perform a complete Bayesian analysis
that determines the posterior distribution of the important parameter,
the common mean, by using the Gibbs sampler. The methodology is
illustrated using two examples. Characteristics such as the mean
and the 95% Credible Region are presented. In example 2, a hypothesis
test is performed.
- Bayesian Estimation of Multinomial Logit Model Regression
Coefficients. Dr. Mary Ann Gregurich.
A Bayesian approach to estimation of the regression coefficients
of a multinomial logit model with ordinal scale response categories
is presented. A Monte Carlo method is used to construct the posterior
distribution of the link function. The link function is treated
as an arbitrary scalar function. The the Gauss-Markov theorem
is used to determine a function of the link which produces a random
vector of coefficients. The posterior distribution of the random
vector of coefficients is used to estimate the regression coefficients.
The method described is referred to as a Bayesian generalized
least square (BGLS) analysis. Two cases involving multinomial
logit models have been described. Case I involves a cumulative
logit model and Case II involves a proportional-odds model. All
inferences about the coefficients for both cases are described
in terms of the posterior distribution of the regression coefficients.
The results from the BGLS method are compared to Maximum likelihood
estimates of the regression coefficients. The BGLS method avoids
the nonlinear problems encountered when estimating the regression
coefficients of a generalized linear model. The method is not
complex or computationallly intensive. The BGLS method offers
several advantages over Bayesian approaches.
- The Internet Survey. Dr. Mary Ann Gregurich and Dr.
Marilyn Greer.
The purpose of this study was to evaluate employee satisfaction
with the Internet, the quality of in-house services, and use of
the Internet as a tool int was developed and tested with a focus
group of employees. The survey was distributed to all faculty
and staff using institutional mail. The response rate was 35.4%
(615 respondents); respondent, reliability, and validity analysis
was completed.
The majority of respondents were faculty members (61.2%) between
36 and 50 years of age (61.4%). E-mail was the most widely used
application (94.1%), followed by the World Wide Web (77.5%). Internet
users (87.8%) responded that the Internet was a valuable tool
in the workplace and 75% responded that it was easy to use. Only
29% of respondents were satisfied with in-house Internet assistance.
Comments suggested that Internet users were dissatisfied with
in-house training availability and home access to the Internet.
Employee use of the Internet will improve the institution's effectiveness
as a research center and cancer hospital. It is recommended that
the study be repeated every two years to assess employee satisfaction
and use of the Internet.
- Surveillance Committee Review for Protocols:
- Dr. Peter F. Thall
- Dr. Su-Chun Cheng
- Dr. Kenneth R. Hess
- Dr. J. Jack Lee
- Dr. J. Lynn Palmer
- Dr. Yu Shen
- Mrs. Terry L. Smith
- Dr. Mary Ann Gregurich
- Breast cancer prognosis in young women
(Recent Publications, #31).
Dr. V. Guinee, Ms. S. Taylor, and Dr. K. Hess.
This study was undertaken to determine possible prognostic factors
in women less than 30 years old with breast cancer. The clinical
presentation and course of treatment was documented for 407 women
aged 20-29 years with histologically-confirmed local or regional
invasive breast carcinoma who registered from 1978 through 1988
at one of nine centers participating in the International Cancer
Patient Data Exchange System. Analysis was performed using Cox
proportional hazards regression analysis. For patients whose breast
cancer was diagnosed during pregnancy, the relative risk of dying
from beast cancer (compared to those who had not been pregnant)
was 3.2 (p = 0.0005, 95% confidence interval: 1.8 to 5.8).
The relative risk, adjusted for number of metastatic axillary
nodes and tumor diameter, was 2.6 (p = 0.036, 95% confidence
interval: 1.1 to 5.8). For each 1-year increment in the interval
between a prior pregnancy and breast cancer diagnosis, the risk
of dying decreased by 15 percent, a relative risk of 0.85 (p
= 0.011, 95% confidence interval: 0.74 to 0.97). Insufficient
data were available to assess the effect of subsequent pregnancy
on survival. However, the magnitude of the effect of a concurrent
or recent pregnancy is such that it should be considered as a
contributing factor in the acknowledged poor prognosis of young
women with breast cancer.
- Risk factors for neurosurgical complications. Dr. R.
Sawaya, Dr. M. Hammoud, and Dr. K. Hess.
Data were collected on 400 craniotomies to determine predictors
of postoperative complications. Complications were scored as major
or minor and systemic or neurological. Data on twelve potential
predictors were analyzed with multiple logistic regression and
classification tree analysis. A total of 53 (13%) cases developed
a major complication: 34 neurologic deficit, 12 other neurologic,
and 11 systemic. Only three patients had multiple types of major
complications. Logistic regression identified age and grade (lesion
in nonfunctional part of brain, near functional part, in functional
part) as significant independent predictors of the occurrence
of major complications. Classification tree analysis also demonstrated
that among the cases with tumors in the nonfunctional parts of
the brain, pathology (glioma or metastasis) was predictive. Of
the 79 patients with metastatic lesions in nonfunctional areas,
only one (1%) developed a major complication. Analysis of factors
related to length of stay was performed using linear regression
and regression tree analyses (with a log (log) transformation
of hospital stay). In addition to age, grade, and pathology, lower
performance scores were found to be associated with prolonged
stays.
- Fecal occult blood testing in a community setting.
Dr. B. Levin, Ms. C. Johnson, and Dr. K. Hess.
A mass screening (80,000 kits distributed) with fecal occult blood
tests was performed in cooperation with a local television station
(Channel 13) and local grocery store chain pharmacies (Randall's).
The goal was to compare three tests manufactured by Smith-Kline
Diagnostics. A Scantron questionnaire was included with the test
kits. A total of 10,633 kits were returned with 1,748 testing
positive on one or more tests. These patients were urged to see
their doctors for further testing. The test positivities ranged
from 5% to 15%, while the positive predictive values in the 1029
patients with clinical follow-up ranged from 6% to 13%. Non-compliance
with dietary and medication restrictions and the presence of gastrointestinal
symptoms increased the positivity rates.
- Unknown primary tumors (Recent Publications,
#1). Dr. J. Abbruzzese
and Dr. K. Hess.
A primary objective of this study was to identify new and verify
existing prognostic factors in patients with unknown primary carcinoma.
Among 927 consecutive patients referred to the Unknown Primary
Clinic between 1987 and 1992, a standardized clinical evaluation
identified 657 patients with unknown primary carcinoma. Data on
age, gender, race, histology and pattern of involved organ sites
were correlated to survival time using Cox proportional hazards
regression analysis. Increasing numbers of involved sites, adenocarcinoma
histology, male gender, and liver involvement were significant
independent predictors of shorter survival times. Neuroendocrine
carcinoma histology and lymph node involvement were significant
independent predictors of longer survival. Based on the prognostic
index computed from the Cox regression analysis, we profiled the
139 lowest-risk patients and the 100 highest-risk patients. We
also analyzed the two-way interactions between the prognostic
factors to determine whether the effects of some factors depended
on the levels of the other factors. Among the patients with isolated
lymph node involvement, it was demonstrated that patients with
supraclavicular nodal involvement had shorter survival and among
patients with isolated liver involvement. Patients with neuroendocrine
metastases had longer survival. In the future, prognostic stratification
will be performed using classification tree analysis. This information
will allow the selection of patients for specific therapeutic
interventions.
- Chemoprevention aerodigestive PO1 project (CAP). Dr.
W. Hong, Dr. S. Lippman, Dr. J. S. Lee, Dr. R. Lotan, Dr. W. Hittelman,
Dr. M. Tainsky, and Dr. J. Lee, and Dr. T. Moon.
The CAP study is a five-year project which includes two Phase
III clinical trials and four basic science research to study the
efficacy and mechanism of retinoid chemoprevention in the aerodigestive
tract. Dr. Lee is the statistician of "Chemoprevention Trial
in Oral Premalignancy" and is responsible for the statistical
issues involved in the design, implementation, and analysis of
this trial. He also provides statistical consultation to the basic
science studies.
- Phase III double-blind randomized trial of 13-cis retinoic
acid to prevent second primary tumors (SPT) in stage I non-small
cell lung cancer. Dr. S. Lippman, Dr. S. Benner, Dr. R. Winn,
Dr. J. J. Lee, Mr. Joel Dubin, and Ms. N. Tu.
As of February, 1995, there were 736 patients registered in this
multi-center clinical trial and among them, 593 were randomized.
It is expected that it will take another two years to reach the
accrual goal of enrolling 1,260 patients. With an additional three
to four years of follow-up, the study will have 80% power in detecting
a 50% reduction in the SPT incidence rate. The study is moving
along well. The accrual rate and compliance rate are on target.
QA and QC procedures are in place to ensure the quality of the
data. Statistical reports are provided every six months.
- Suppression of retinoic acid receptor b in oral premalignant
lesions and its upregulation by isotretinoin. Dr. R. Lotan,
Dr. S. Lippman, and Dr. J. Lee.
Data from 52 oral leukoplakia patients indicated that only 40%
of the lesions expressed RAR-ß at baseline while 100% expression
was found in normal controls. It was found that, after 3-month
of high-dose isotretinoin treatment, 90% of the lesions expressed
RAR-ß (p=.00001, McNemar's test). The upregulation of RAR-ß
is correlated with clinical response (p=.039, Fisher's exact test).
The result suggests that RAR-ß expression is an excellent
biomarker for retinoid chemoprevention trials in oral carcinogenesis.
- Relationship of P-glycoprotein and CEA expression in human
colon carcinoma to local invasion, DNA ploidy, and disease relapse.
Dr. F. Sinicrope and Dr. J. Lee.
Among a total of 52 Stage B2 colon cancer patients, P-glycoproteins
were detected in 44 and 42 patients by JSB-1 and HYB-241 and CEA
was found in 50 patients. In a multivariate analysis, a high level
of P-gp expression, DNA aneuploidy, microinvasion, and single
carcinoma cell invasion were found to be significant predictors
of disease relapse. The results indicate that diffuse P-gp expression
is present in the majority of Stage B2 colon cancer and can be
of prognostic value in predicting disease recurrence.
- Prognostic value of size of lymph node metastases in patients
with cutaneous melanoma. Dr. A. Buzaid, Dr. S. Legha, Dr.
R. Benjamin, Dr. J. Lee, and Ms. N. Tu.
In a retrospective study of 442 melanoma patients, it was found
that the number of positive nodes, age, and tumor thickness were
significant prognostic factors for survival. On the other hand,
the size of the nodal mass by either physical examination or pathology
were not of prognostic value and should be eliminated from the
current staging system.
- p53 and retinoid chemoprevention of oral carcinogenesis.
Dr. S. Lippman, Dr. D. Shin, and Dr. J. Lee.
The patterns of p53 expression, association with retinoid treatment
and modulation were studied in 40 patients with oral premalignant
lesions. It was found that the accumulation of p53 had a direct
association with histology grade and an inverse correlation was
found between the baseline p53 expression and treatment response.
- Trisomy 7: A potential cytogenetic marker of human prostate
cancer rogression. Dr. M.G. Bandyk, Dr. L. Zhao, Dr. P. Troncoso,
Dr. L.L. Pisters, Dr. A.C. von Eschenbach, Dr. L.W.K. Chung, Dr.
J.C. Liang, and Dr. J.L. Palmer.
The technique of fluorescence in situ hybridization (FISH)
was employed to demonstrate that chromosome 7 trisomy is associated
with the progression of human prostate cancer to advanced stages
and to metastatic sites such as the bone marrow. Thirty-five human
specimens including 14 primary prostate tumors, 16 metastatic
lesions, and 5 normal prostate tissues were examined for the presence
of chromosome 7 aneuploidy. In addition two prostatic tumor cell
lines of different tumorigenic potential were also evaluated for
the copy number of chromosome 7. Results showed that the androgen-unresponsive
and tumorigenic cell line PC-3 exhibited a significantly higher
ratio of chromosome 7 to total chromosome number than the androgen-responsive,
non-tumorigenic cell line. In the human prostate specimens, significantly
elevated frequencies of trisomy 7 cells were observed in the advanced
stage tumors as compared to the early stage tumors and normal
prostatic tissue. Furthermore, metastases were found to have a
significantly higher frequency of trisomy 7 cells than primary
tumors. Trisomy 7 was apparently not due to triploidy of the cells
because when chromosome 9 was used as an internal control, all
primary tumors and metastases were predominantly disomic for this
chromosome. Also, in two patients with paired primary and metastatic
tumors, the percentage of trisomy 7 cells increased from 4-7%
in the primary tumors to 42-45% in the metastatic prostate tumor
cells in the bone marrow. Therefore, our data suggest that trisomy
7 may be a common feature associated with the local and metastatic
progression of human prostate cancer and may serve as a novel
marker for human prostate cancer progression.
- p53 protein accumulation in the progression of human prostate
carcinoma. Dr. N.M. Navone, Dr. P. Troncoso, Dr. L.L. Pisters,
Dr. A.C. von Eschenbach, Dr. C.J. Conti, and Dr. J.L. Palmer.
Nuclear accumulation of the p53 protein has been shown to be strongly
associated with p53 mutations. Previous studies on accumulation
of the p53 protein in prostate carcinoma have been confined to
primary tumors. We studied the accumulation of p53 protein in
specimens obtained from primary and metastatic sites of prostate
carcinoma. This study was designed to understand the role of p53
mutation in the progression of prostate carcinoma and to determine
the relationship between accumulation of this protein with stage,
histologic grade and androgen responsiveness of the tumor. We
studied the accumulation of the p53 protein by means of immunohisto-chemical
methods using the polyclonal antibody to human p53. The material
studied consisted of formalin fixed, paraffin-embedded tissue
obtained from primary tumors and metastases of 92 cases of prostate
carcinoma. All tumors with p53 accumulation were metastatic, poorly
differentiated and androgen independent. Results showed that p53
accumulation had a strong association with stage, grade, and androgen
sensitivity. Logistic regression analysis demonstrated that androgen
sensitivity predicted p53 outcome better than stage or grade alone.
- Significance of tumor size and radiation dose to local
control in stage I-III diffuse large cell lymphoma treated with
chop-bleo and radiation. Dr. L.M. Fuller, Dr. P. McLaughlin,
Dr. A. Rodriguez, and Dr. J.L. Palmer.
The purpose of this study was to evaluate the possible effect
of adjunctive involved field radiotherapy on long-term local control
for patients with Ann Arbor Stage I-III diffuse large cell lymphoma
who achieved a complete remission on a combined modality program
which included cyclophosphamide, doxorubicin, vincristine, prednisone,
and Bleomycin (CHOP-Bleo). One hundred and ninety patients were
included in this study. Analyses were made to determine response
to treatment according to stage, extent of maximum local disease
and irradiation dose. Relapse patterns were also studied. A complete
remission was achieved in 162 patients. Among patients who achieved
a complete response, local control was better for those who received
tumor doses of
40 Gy (97%) than for those who received < 40 Gy (83%). Among
those with extensive local disease, the corresponding control
rates were 88% and 71%, respectively.
- Analysis of lymphangiogram and laparotomy findings in relation
to staging in adult patients with Hodgkin's disease. Dr. L.
Fuller, Dr. N. Mirza, and Dr. J.L. Palmer.
The objective of this study is to determine prognostic factors
which correctly predict a positive finding of Hodgkin's disease
by lymphangiogram; and for those patients with a negative lymphangiogram,
which factors would predict a correct positive finding of the
disease by laparotomy. Laparotomies are being eliminated as sequential
staging procedures, but a large data base is available for past
procedures performed at M.D. Anderson.
- Second-line treatment for breast cancer patients. Dr.
R. Winn, Dr. M. Weitzner, Dr. C. Meyers, Dr. J. Palmer and others.
The objectives of this study are to determine what variables predict
whether or not a breast cancer patient will receive second-line
chemotherapy and which predict whether or not a breast cancer
patient who receives second-line chemotherapy will respond. The
study will also attempt to determine outcomes (in terms of survival,
quality of life) for breast cancer patients who do and who do
not receive second-line chemotherapy (and who do and do not respond).
Since this is not a randomized study, efforts were made to insure
that patients compared were equivalent in terms of major clinical
variables.
- Evaluation of interferon therapy for treatment of chronic
myelogenous leukemia (CML). Dr. H. Kantarjian and Mrs. T.
Smith.
Approximately one-third of patients with early stage CML achieve
a cytogenetic response (significant reduction of Philadelphia
chromosome), sometimes after prolonged therapy with interferon.
We were able to show that risk of death is reduced in these patients,
compared to those with no or lesser response. In addition to the
Philadelphia chromosome, patients with CML often develop other
chromosomal abnormalities during the long course of their disease.
Recursive partitioning methods are being used in an exploratory
phase of investigation into the impact on survival of the various
types of abnormalities. This analysis is based on a large series
of patients treated with interferon.
- Staging of chronic lymphocytic leukemia (CLL). Dr.
M. Keating and Mrs. T. Smith.
Classical staging systems, such as those of Rai and Binet, were
developed prior to the advent of effective chemotherapy agents
such as fludarabine. Since 1984, several hundred CLL patients
have been treated at MDACC on fludarabine regimens. Factors associated
with treatment response and survival have been investigated in
this population; inclusion of additional factors resulted in prediction
models that categorized patients more accurately than traditional
staging systems when tested in an independent group of CLL patients.
A large patient population with early stage CLL not requiring
fludarabine therapy is also being investigated to determine if
inclusion of information on such characteristics as B2-microglobulin
can improve on previous staging systems.
- Evaluation of breast cancer treatment programs. Dr.
G. Hortobagyi, Dr. A. Buzdar, Dr. F. Holmes, and Mrs. T. Smith.
Many large clinical trials are underway evaluating various strategies
for the treatment of both early stage and advanced forms of breast
cancer, and statistical methods are applied for the design and
analysis of these trials. An investigation of the role of radiotherapy,
and whether it may be associated with the development of second
cancers, is underway. Other studies involve the role of hormone
therapy, intensified therapy with bone marrow transplantation,
and the timing of various components of therapy.
- Predicting the need for blood transfusion following surgery
for head and neck cancer. Dr. R. Weber and Mrs. T. Smith.
A model incorporating several pre-surgery factors has been developed
to predict which patients undergoing surgery for head and neck
cancer are likely to require blood transfusion. This would allow
more efficient decisions regarding directed blood donations. Data
are being collected on recent patients so that the model may be
subjected to testing before it is recommended for prospective
application.
- Adenocarcinoma as an independent risk factor for recurrence
in patients with stage IB cervical carcinoma. Dr. P. Eifel
and Mrs. T. Smith.
The objective of this investigation is to determine the influence
of histologic type on outcome in patients with stage IB carcinoma
of the cervix treated with radiotherapy. A draft manuscript has
been written and is under review.
- Use of G-CSF before, during, and after
fludarabine+ ara-C induction therapy of newly-diagnosed AML or
MDS: Comparison of fludarabine + ara-c without G-CSF (Recent
Publications, #24).
Dr. E. Estey, Dr. P. Thall, Dr. M. Andreeff, Dr. M. Beran, Dr.
H. Kantarjian, Dr. S. O'Brien, Dr. S. Escudier, Dr. L.E. Robertson,
Dr. C. Koller, Dr. S. Kornblau, Dr. S. Pierce, Dr. E.J Freireich,
Dr. A. Deisseroth, and Dr. M. Keating.
Two lines of evidence suggest that the use of granulocyte colony-stimulating
factor (GCSF) might be beneficial in the management of untreated
acute myelogenous leukemia (AML). Japanese investigators have
found that administration of GCSF following completion of chemotherapy
shortens the duration of neutropenia by about one week and also
reduces the infection rate among previously treated AML patients.
In vitro data suggest that GCSF administered before, during,
and shortly after ara-C may sensitize leukemia cells to the drug.
In this paper, the clinical effects of GCSF administered in this
manner with fludarabine + ara-C (FLAG), compared to fludarabine
+ ara-C alone (FA), are investigated. Logistic regression analyses
of 112 FLAG patients and 85 FA patients, from consecutive studies,
showed accelerated neutrophil recovery with FLAG, but no significant
difference in complete remission rate between FLAG and FA.
- Phase II study of accelerated fractionation
radiation therapy with carboplatin followed by PCV chemotherapy
for the treatment of glioblastoma multiforme (Submitted Publications,
#14). Dr. V.A.
Levin, Dr. P.F. Thall, Dr. M.H. Maor, Dr. W.K.A. Yung, Dr. J.
Bruner, Dr. R. Sawaya, Dr. A. Kyritsis, Dr. S. Woo, Dr. L. Rodriguez,
and Dr. M.J. Gleason.
In the past 20 years, numerous drug-radiation combinations have
been tried in an attempt to improve the survival of patients with
glioblastoma multi-forme (GBM). This paper describes a phase II
one-arm study to evaluate the long-term efficacy and safety of
accelerated fractionated radiotherapy combined with intravenous
carboplatin for patients with previously untreated glioblastoma
multiforme tumors.
Eighty-three patients received 1.9-2.0 Gy radiation three times
a day with 2-h infusions of 33 mg/m2 carboplatin for
two 5-day separated by 2 weeks; following radiotherapy, patients
received procarbazine, lomustine (CCNU), and vincristine (PCV)
for 1 year or until progression.
Seventy-four of the 83 patients (89%) received one or more courses
of PCV; their median survival was 55 weeks. Total resection was
performed in 20%, subtotal resection in 69%, and biopsy in 11%;
reoperation (total or subtotal resection) was performed in 37%
of patients. Survival was worst for those
61 years old (median 35 weeks). Covariates individually
predictive of improved survival were younger age, smaller radiation
volume, total or subtotal resection vs. biopsy, and higher Karnofsky
performance status. A multivariate analysis showed that age and
extent of initial surgery together were predictive of a better
survival with no other variables providing additional significance.
Only 8.4% of patients had therapy-associated neurotoxicity ("radiation
necrosis").
When comparable selection criteria were applied, the survival
in this study is similar to the results currently attainable with
other chemoradiation approaches. The relative safety of accelerated
fractionated radiotherapy, as used in this study with carboplatin,
enables concomitant full dose administration of chemotherapy or
radio-sensitizing agents in GBM patients.
- Prognostic significance of preoperative
MRI scans in gliobastoma multiforme (Submitted Publications,
#7). Dr. M.A. Hammoud,
Dr. R. Sawaya, Dr. W. Shi, Dr. P.F. Thall, and Dr. N.E. Leeds.
Tumor necrosis, enhancement, and associated edema in patients
with gliobastoma multiforme (GBM) represent biological variables
that can be quantitated on preoperative MRI scans. We reviewed
48 high selected patients, all of whom had supratentorial lesions,
underwent gross total tumor resection, and received adjuvant radio-
and chemotherapies. None had prior surgery. The median age was
50 years. The median Karnofsky performance score was 80. Cox regression
analysis revealed that the strongest prognostic variable is the
amount of tumor necrosis on preoperative scan, with median survivals
of 42, 24, 15, and 12 months for tumor necrosis grades of 0, I,
II, and III, respectively. The intensity of enhancement of the
tumor nodule is also prognostic, with median survivals of 35,
18, and 13.5 months for enhancement grades of 0, I, and II, respectively.
The extent of peritumoral edema has a quadratic effect, with grades
I, II, and III surviving for 24, 12, and 20 months respectively.
In conclusion, GBM patients with little or no necrosis and with
less tumor nodule enhancement on preoperative MRI survive longer
than patients with greater amounts of necrosis and with less tumor
nodule enhancement on preoperative MRI survive longer than patients
with greater amounts of necrosis and greater degrees of tumor
enhancement. In addition, a moderate degree of peritumoral edema
is associated with worse prognosis.
- Evaluation of Short-Chain Fatty Acid Enemas:
Treatment of Radiation Proctitis (Recent Publications, #3).
Dr. R. Al-Sabbagh, Dr. F.A. Sinicrope, Dr. J.H. Sellin, Dr. Y.
Shen, and Dr. L. Roubein.
Radiation proctitis is a common complication of abdominal and
pelvic radiotherapy; unfortunately, there is no established effective
therapy for radiation proctitis. Short-chain fatty acids (SCFA)
have been effectively used to treat a variety of colitides. We
sought to determine whether SCFA enemas have a role in the treatment
of radiation proctitis. Results: Four weeks of treatment with
SCFA enemas resulted in clinical improvement in all patients.
There were modest, but not significant, changes in endoscopic
and pathological parameters. Therefore, SCFA is a promising therapeutic
option in radiation proctitis.
- Elevated Soluble Fas Levels in Nonhemotopoietic
Human Malignancy (Submitted Publications, #16).
Dr. G.P. Midis, Dr. Y. Shen and Dr. L.B. Schaub
Fas is a widely expressed membrane-anchored protein that induces
apoptosis. Soluble Fas (sFas), generated by alternative mRNA splicing,
can antagonize cell-surface Fas function. We have investigated
sFas in 104 cancer patients with nonhematopoietic malignancies
using a Fas-specific ELISA and immunoprecipitation. Our studies
demonstrate an elevated 40-42 kDa sFas species in both patient
serum and tumor explants. These observations provide the first
evidence that sFas is increased in patients with solid tumors
in a manner reflective of disease stage and tumor burden and argue
that sFas can be synthesized and released both systemically and
locally within the tumor microenvironment.
- Increased Apoptosis Accompanies Neoplastic
Development in the Human Colorectum (Recent Publications,
#75). Dr. F.A.
Sinicrope, Dr. G. Roddey, Dr. T.J. McDonnell, Dr. Y. Shen, Dr.
K.R. Cleary and Dr. C. Stephens.
A disturbance in the balance between cell proliferation and cell
loss, or apoptosis, may underlie neoplastic development. Therefore,
we determined spontaneous apoptotic and proliferative rates in
normal, hyperplastic, adenomatous, and malignant colorectal epithelia.
In normal mucosa, luminal epithelial cells demonstrated higher
rates of apoptosis compared to cells in the proliferative zone.
Neoplastic transformation was associated with a significant increase
in rates of apoptosis and proliferation. However, apoptosis, but
not proliferation, decreased at the adenoma to carcinoma transition
coincident with expression of mutant p53. In carcinomas, both
mutant p53 and bcl-2 protein levels were associated with attenuated
apoptotic rates. In conclusion, apoptosis is an important regulator
of growth in normal and neoplastic epithelia.
- Loss of p21 Protein Expression Accompanies
Neoplastic Progressionin Human Colorectalum (Submitted Publications,
#19). Dr. G. Roddey,
Dr. S. Ruan, Dr. C. Stephens, Dr. M.L. Frazier, Dr. G. Glober,
Dr. Y. Shen, Dr. W. Zhang, and Dr. F.A. Sinicrope.
p21, a cyclin-dependent kinase inhibitor, can be transcriptionally
activated by p53 and mediates cell cycle arrest. We analyzed p21
expression during colorectal tumorigenesis and its relationship
to p53, bcl-2, and to rates of proliferation and apoptosis. No
relationship between p21 and proliferative or apoptotic labeling
indices, or with bcl-2 expression, was found in neoplasms. In
conclusion, a reduction in the frequency of p21 expression and
altered topography accompany colorectal neoplastic development
and progression. These findings suggest that p21 is an early target
of alteration and that loss of negative cell cycle regulation
may be a critical event in colorectal tumorigenesis. The lack
of correlation between p21 and p53 expression suggests that p21
may be regulated by p53-independent pathways.
Other Consultations and Collaborations
- Critical determinants of aggressive skin cancer program project
(application). Dr. M. Kripke, Dr. T. Moon, and Dr. J. Lee.
- Chemoprevention trial in oral premalignancy. Dr. S. Lippman,
Dr. R. Winn, Dr. J. Lee, Dr. G. Clayman, and Dr. T. Moon.
- Genetic alterations in PUVA-induced skin cancers. Dr. H. Ananthaswamy
and Dr. T. Moon.
- Medical informatics patient studies unit. Dr. M. Morris and
Dr. T. Moon.
- Institutional data monitoring. Dr. M. Keating and Dr. T. Moon.
- Molecular investigation of etiological factors in hepatocellular
carcinoma in the U.S. Dr. Y. Patt, A. Hogue, and Dr. T. Moon.
- Therabite mobilizer for maxillary resection. Dr. R. Jacob
and Dr. T. Moon.
- Smoking cessation among school children. Dr. A.V. Prokhorov
and Dr. T. Moon.
- Retrograde cerebral perfusion in pigs. Dr. H. Safi and Dr.
K. Hess.
- Cerebral spinal fluid drainage and distal aortic perfusion
in surgery for thoracoabdominal aortic aneurysms. Dr. H. Safi
and Dr. K. Hess.
- Bcl-2 in medulloblastoma. Dr. J. Bruner and Dr. K. Hess.
- p53 correlations in breast cancer. Dr. M. Cervantes and Dr.
K. Hess.
- Radiosurgery for brain metastases. Dr. R. Sawaya, Mr. R. Bindal,
and Dr. K. Hess.
- MIB-1 antigen and BudR in meningioma. Dr. L. Langford, Ms.
C. Cooksley, and Dr. K. Hess.
- Prognostic factors in melanoma of the foot. Dr. J. Reilly,
Mr. G. Giacco, and Dr. K. Hess.
- Pelvic exenteration for rectal carcinoma. Dr. J. Skibber,
Mr. G. Giacco, and Dr. K. Hess.
- Improved contrast-enhanced MRI of the breast. Dr. K. Wright
and Dr. K. Hess.
- Fibroblast growth factor receptor alterations in human gliomas.
Dr. R. Morrison and Dr. K. Hess.
- Latent primary malignancies. Dr. J. Abbruzzese and Dr. K.
Hess.
- Reoperation for metastatic brain tumor. Dr. R. Sawaya, Mr.
R. Bindal, and Dr. K. Hess.
- Melanoma metastatic to GI tract. Dr. H. Gutman and Dr. K.
Hess.
- Contrast-enhanced MRI of the liver. Dr. M. Fenstermacher and
Dr. K. Hess.
- Detecting axillary lymph nodes in breast cancer. Dr. S. Wallace
and Dr. K. Hess.
- Heart rate variability. Dr. T. Vybiral and Dr. K. Hess.
- Sequential annual immunization with influenza vaccine. Dr.
W. Keitel and Dr. K. Hess.
- High doses of purified influenza vaccine. Dr. W. Keitel and
Dr. K. Hess.
- Aggressive meningeal tumors. Dr. R. Sawaya, Mr. G. Younis,
and Dr. K. Hess.
- BUdR labeling in glioblastoma multiforme. Dr. R. Sawaya, Dr.
A. Ritter, and Dr. K. Hess.
- Sarcoma brain metastases. Dr. R. Sawaya, Mr. R. Bindal, and
Dr. K. Hess.
- Phase II and III Trials for comparing the combined effect
of cis-retinoic acid, alpha-interferon and radiation versus radiation
alone in metastatic cervical cancer. Dr. S. Lippman, Dr. I. Krakoff,
and Dr. J.J. Lee.
- Correlation of PSA, retinol, and 13-cRA level in oral leukoplakia
patients. Dr. S. Lippman, Dr. H. Fritsche, and Dr. J. Lee.
- Expression of p53 oncoprotein in non-small cell lung cancer:
A favorable prognostic factor? Dr. J.S. Lee, Dr. J. J. Lee, and
Ms. N. Tu.
- Phase I trial of chemoradiation therapy with taxol and brachytherapy
for patients with NSCLC. Dr. J. S. Lee and Dr. J. J. Lee.
- Bronchial squamous metaplasia chemoprevention trial. Dr. W.K.
Hong, Dr. J.S. Lee, and Dr. J. Lee.
- Lung cancer chemoprevention with synthetic retinoid 4-HPR.
Dr. W. K. Hong, Dr. E. Gehan, and Dr. J. Lee.
- Primary and secondary prevention of lung cancer. Dr. W. K.
Hong, Dr. J. J. Lee, Dr. M. Spitz, and Dr. C. Amos.
- Lung cancer chemoprevention research program (U19). Dr. W.K.
Hong, Dr. J. Kurie, Dr. W. Hittelman, Dr. R. Lotan, and Dr. J.
Lee.
- The prognostic effect of p53 expression in head and neck cancer
patients. Dr. D. Shin, Dr. W. Hittelman, Dr. J. Lee, and Ms. N.
Tu.
- Combined therapy of high-dose 13cRA, alpha interferon and
CDDP in patients with stage III/IV head and neck SCC. Dr. D. Shin
and Dr. J. Lee.
- High proliferation cell nuclear antigen expression predicts
poor survival in patients with head and neck squamous cell carcinoma.
Dr. D. Shin and Dr. J. Lee.
- A phase II study of topotecan in patients with advanced non-small
cell lung cancer previously untreated with chemotherapy. Dr. R.
Perez-Soler and Dr. J. J. Lee.
- Micronuclei analysis on the high-dose induction, low-dose
maintenance, oral leukoplakia trial. Dr. S. Benner and Dr. J.
J. Lee.
- Phase I trials of new anti-cancer agents. Dr. M. Raber, Dr.
J. Lee, and Dr. E. Gehan.
- DNA repair in biochemotherapy of melanoma. Dr. F. Ali-Osman,
Dr. A. Buzaid, and Dr. J. Lee.
- Macrophages and cytokines in biochemotherapy of melanoma.
Dr. E. Grimm, Dr. A. Buzaid, and Dr. J. Lee.
- Protective effects of in vivo 13-cis-retinoic acid
treatment against mutagen-induced genetic damage. Dr. Z. Trizna
and Dr. J. Lee.
- A randomized study of vitamin E versus placebo in the prevention
of treatment induced mucositis. Dr. C. Verschraegen and Dr. J.
Lee.
- Melphalan-taxol dose finding study. Dr. D. Gershenson, Dr.
P. Thall, and Dr. J. J. Lee.
- Is follow-up of lung cancer patients following resection medically
indicated and cost effective? Dr. G. Walsh and Dr. J. Lee.
- Lung cancer risk assessment among ex-smokers. Dr. M. Spitz
and Dr. J. Lee.
- Phase II study of adriamycin, ifosfamide and platinum on sarcomas.
Dr. S. Patel and Dr. J. Lee.
- Master agreement application -- Phase I Chemoprevention Agents.
Dr. B. Levin and Dr. J. Lee.
- Subcutaneous heparin in reducing the pulmonary embolism and
venous thrombosis in patients receiving thoracic surgery. Dr.
J. B. Putnam, Jr. and Dr. J. Lee.
- A randomized comparison of intravenous versus thoracic epidural
sufentanil for analgesia in adult patients. Dr. J. C. Nesbitt
and Dr. J. Lee.
- The combination therapy of 13-cis-retinoic acid with alpha-interferon
in treating aggressive squamous carcinoma of the skin. Dr. G.
Clayman, Dr. S. Lippman, and Dr. J. Lee.
- Quantitative DNA analysis by PCR. Dr. J. Roth, Dr. R. A. White
and Dr. J. Lee.
- Calcium carbonate therapy of diarrhea in intestinal bypass
patients. Dr. G. Steinbach and Dr. J. Lee.
- Studies on the role of H. Pylori in the immunopathogenesis
of MALT lymphomas. Dr. G. Steinbach and Dr. J. Lee.
- Using p65 staining as a screening tool for diagnosing colon
cancer. Dr. G. Steinbach, Dr. J.J. Lee, and Ms. N. Tu.
- Expression of the bcl-2, p53, and p-glycoproteins during colorectal
tumorigenesis. Dr. F. Sinicrope and Dr. J. J. Lee.
- The design and analysis of human colorectal epithelial cell
proliferation studies using the labeling index as an intermediate
marker. Dr. M. Wargovich, Dr. G. Steinbach, Dr. R. Winn, and Dr.
J. Lee.
- Reliability analysis of computerized scoring system of colon
epithelial cell proliferation index. Dr. M. Wargovich, Dr. J.
J. Lee, and Mr. J. Dubin.
- Protocol DM 89-08: Utility of a panel of intermediate markers
in predicting colonic adenomatous polyp recurrence. Dr. R. Winn,
Dr. M. Wargovich, Dr. J. J. Lee, and Ms. N. Tu.
- Time to hematopoietic recovery after high-dose cyclophosphamide,
etoposide and cisplatin. Dr. R. Champlin, Dr. D. Seong, and Dr.
J. Palmer.
- High dose tandem chemotherapy with or without autologous bone
marrow transplantation. Dr. D. Seong and Dr. J. Palmer.
- Blood stem cell transplantation in patients with high risk
hematologic malignancies. Dr. M. KÖrbling and Dr. J. Palmer.
- Pancreatic patient quality-of-life study. Dr. R. Winn, Dr.
R. Pazdur, and Dr. J. Palmer.
- Phase I clinical trials of anticancer agents. Dr. J. Abbruzzese,
Dr. M. Raber, and Dr. Palmer.
- Survival differences in three groups of colon cancer patients.
Dr. R. Pazdur and Dr. J. Palmer.
- A phase I-II study of induction chemotherapy followed by radiotherapy
and concomitant boost chemotherapy in patients with locally advanced
nasopharyngeal carcinoma. Dr. B. Glisson and Dr. J. Palmer.
- Phase II study of topotecan and ara-C in MDS and CML patients.
Dr. M. Beran, Dr. H. Kantarjian, and Dr. J. Palmer.
- Genotoxic effects of multiple cycles of eight chemotherapeutic
agents on mouse germinal stem cells. Dr. P. Sen, Dr. M.L. Meistrich,
Dr. M. Kattan, Dr. J.C. Liang, and Dr. J.L. Palmer.
- Androgen independent growth in prostate cancer. Dr. C.J. Conti,
Dr. L. Chung, Dr. P. Troncoso, Dr. A.C. von Eschenbach, Dr. N.
Navone and Dr. J.L. Palmer.
- Clinical trials of biological response modifiers. Dr. J.L.
Murray, Dr. R. Freedman, Dr. H.M. Vriesendorp, Dr. S.M. Quadri,
Dr. D.A. Podoloff, Dr. D.J. Macey, Dr. L.P. Kasi, Dr. H.Z. Zhang,
Dr. R. Katz, Dr. M. Raber, and Dr. J.L. Palmer.
- Quality of life measurement in newly diagnosed patients with
intermediate grade non-Hodgkin's lymphomas. Dr. M.A. Rodriguez,
W. Swanson, and Dr. J.L. Palmer.
- Phase I-II studies for patients with small cell lung cancer.
Dr. B. Glisson, Dr. R. Komaki, and Dr. J.L. Palmer.
- A comparison of the sensitivity of blood and
bone marrow for the presence of the Ph+ chromosome in chronic
myelogenous leukemia by fluorescent in situ hypridization.
(Submitted Publications, #22).
Dr. D. Seong, Dr. P.F. Thall, Dr. H. Kantarjian, Dr. J. Swantkowski,
Dr. J. Xu, Dr. Y. Shen, Dr. S. Zimmerman, Dr. A. Glassman, Dr.
L. Ramagli, Dr. E. Freireich, Dr. R. Champlin and Dr. M. Siciliano.
- Multi-institutional phase I trial of Cox-2 inhibitor, piroxicam-DFMO,
piroxicam versus sulindac control for patients with colorectal
segment or duodenal polyps. Dr. Steinbach, Dr. Shen, Dr. Zimmerman,
et al.
- Cooperative family registry for epidemiologic studies of colon
cancer. Dr. P. Lynch, Dr. C. Amos, Dr. Y. Shen, et al.
- Study of mechanisms of Fos induced osteosarcoma and cell transformation.
Dr. P. Chiao, Dr. D. Cromeens, Dr.Y. Shen, et al.
- Estimate the misclassification probabilities and test for
the technician effect associated with the FISH method. Dr. A.
Glassman, Dr. Y. Shen, Dr. P.F. Thall.
- A Phase II clinical trial for preoperative chemoradiation
therapy in patients with gastric adenocarcinoma. Dr. P. Mansfield,
Dr. Y. Shen, et al.
- Risk factors for time to death in advanced colon carcinoma
patients. Dr. G. Roddey, Dr. Y. Shen, and Dr. F.A. Sinicrope.
Biostatistical Resource Group
Background
The University of Texas M.D. Anderson Cancer Center has been committed
to clinical research for over 50 years. Currently, there are over
400 clinical studies in progress which have a range of biostatistical
needs, including study design, assessment of feasibility, quality
assurance of database management, statistical analysis, and reporting
of results. Studies underway encompass pilot, phase I, II, and
III clinical trials as well as observational studies of therapeutics,
translational and cancer control objectives.
Studies vary in their requirements for biostatistical collaboration.
Some require only simple statistical analysis. Most require extensive
interactions in the planning and design phase, the conduct and
database management phase, and the analysis and reporting phase.
To maximize the cost effectiveness of contemporary clinical research,
more sophisticated biostatistical methods must be used. Frequently,
adaptation and development of biostatistical methods are required
to ensure maximal use of data from cancer research. Biostatistical
education and training of physicians and basic scientists is essential
to high quality clinical and translational research.
An institution-wide Biostatistical Resource Group was established
for all clinical investigators for training in biostatistics and
for collaboration in clinical research. The Biostatistical Resource
Group was organized in 1986 and has been funded as a Shared Resource
of the Cancer Center Support ("Core") Grant, CA16672,
to The University of Texas M.D. Anderson Cancer Center (Dr. F.F.
Becker, Principal Investigator).
Functions
Major functions include:
- Provision of biostatistical consultation and resources in
statistical computing and database management to institutional
scientists engaged in the planning, conduct, analysis, interpretation,
and reporting of clinical trials and observational studies. Collection
of the data accruing on studies is the responsibility of the scientist.
Advice is provided on computerized database management and the
establishment and quality assurance of appropriate data management
procedures.
- Continue the education and training in biostatistical methods
and clinical research. An entire course and a series of lectures
is being prepared in the areas of design, conduct, analysis, interpretation,
and reporting of clinical research.
- Continue research on biostatistical methods for clinical research.
The program of the Biostatistical Resource Group thus complements
the ongoing activities of the Section of Biostatistics and provides
a visible mechanism for enhancing the quantitative research environment
at The University of Texas M.D. Anderson Cancer Center.
Table of Contents
Section of Computer Science