On the problem of the characterization of late effects by a linear-quadratic survival function. II. Some clinical applications.

On the basis of a previous publication, where radiobiological data of acute and late tissue responses have been analyzed by a linear-quadratic survival function SLQ, clinical observations referring preferably to the postoperative irradiation of mamma carcinoma are presented. Thus the qualitative behavior of radiobiological isoeffect slopes being steeper for late tissue responses than for acute effects can be confirmed by this analysis. However, a statistical analysis of the clinical observations will indicate that late effects and, in particular, the average latency period of their clinical manifestation is mainly dependent on the volume factor.