Comparison of clinical protocols through the mathematical results analysis of survival curves.

In an effort to establish a survival curve model which could help to evaluate adjuvant therapy, two equations were presented to approximate the various clinical curves. These curves usually show three different segments, describing high-risk, intermediate-risk and low-risk groups. The percentage of patients and the annual mortality in each risk group can be calculated from the coefficients of the equation. The present study analysed the survival curves of variously treated uterine cancer and stomach cancer after resection on the one hand, and of adjuvant therapy of breast cancer, malignant melanoma and acute lymphoid leukaemia on the other hand. This method of analysis should be useful for understanding and comparison of curves of phase III trials.