NEW APPROACH TO THE ANALYSIS OF SURVIVAL DATA

Attempts to compare radiation-survival data from a variety of biological systems using conventional survival curve parameters often fail to reveal consistent patterns of response with respect to cell age, drug concentration, LET. From a purely empirical approach and an analysis of data from a variety of biological systems the authors have introduced several new parameters, defined without regard to assumed mechanisms of radiation action. The use of these parameters appears to provide a high degree of consistency in patterns of radiation response in a variety of situations. Furthermore, analysis of a variety of data suggests that certain drugs, such as BUdR, and also high-LET radiations can be treated as though they were the equivalents of additional doses of radiation. Analysis of this information has led to the development of an analytic expression for survival which might be useful for predicting the response to radiations of varying LET and to radiation in the presence of certain classes of radiation-modifying agents such as BUdR.