Related Experiment Video
Updated: Jun 8, 2025

Competing-Risk Nomogram for Predicting Cancer-Specific Survival in Multiple Primary Colorectal Cancer Patients after Surgery
Published on: September 27, 2024
Estimating cure proportion in cancer clinical trials using flexible parametric cure models
Yuka Sano1, Shiro Tanaka2, Tosiya Sato3
1Data Science Department, National Cerebral and Cardiovascular Center, Osaka, Japan. sano.yuka@ncvc.go.jp.
Estimating cancer cure proportion requires careful cure model selection. Flexible parametric cure models can be sensitive to knot placement, impacting cure estimates in clinical trials.
Area of Science:
- Biostatistics
- Clinical Trials
- Cancer Research
Background:
- Estimating the cure proportion is crucial in cancer clinical trials.
- Cure models implicitly define a cure point, but its impact on estimates is unclear.
Purpose of the Study:
- To assess the sensitivity of cure proportion estimates to knot placement in flexible parametric cure models.
- To evaluate model performance and cure point determination using simulation.
Main Methods:
- Utilized data from the CheckMate 141 immuno-oncology clinical trial.
- Examined knot number and placement in flexible parametric cure models.
- Conducted a simulation study to evaluate model performance.
Main Results:
- The last knot's position significantly impacted cure proportion estimates and model fit.
- Placing the last knot at the last observed event time led to overestimation.
- Bias was reduced by placing the last knot later.
Conclusions:
- Flexible parametric cure models offer an alternative to the Kaplan-Meier method for cure proportion estimation.
- Careful consideration of cure point placement is essential for accurate estimates.
Related Concept Videos
Cancer Survival Analysis
Kaplan-Meier Approach
Comparing the Survival Analysis of Two or More Groups
Survival Curves
The Kaplan-Meier estimator is the most common method for constructing survival curves. This...
Actuarial Approach
Consider the example of a high-risk surgical procedure with significant early-stage mortality. A two-year clinical study is conducted,...
Parametric Survival Analysis: Weibull and Exponential Methods
Weibull Distribution
The Weibull distribution is a flexible model used in parametric survival analysis. It can handle both increasing and decreasing hazard rates, depending on its shape parameter...

