Dose-Response Relationships for Late Effects on Skin and Mucosa

The dose-response relationship is a very fundamental concept in radiotherapy for treatment of malignant diseases. The Poisson statistics, the number and types of target cells or functional tissue units, and their radiosensitivity determine the location and steepness of the dose-response curve in an individual patient. However, the dose-response curve estimated from a group of patients is always flatter than the individual one due to heterogeneity concerning the number and radiosensitivity of the target units and variation in the absorbed dose (Gilbert 1974; Thames and Hendry 1987).