Electron beam treatment in post-operative management of carcinoma of the breast : influence of overall treatment time and bioeffect models

Time dose fractionation (TDF) factor has been shown to poorly describe the effect of changes in dose per fraction and overall treatment time, both in acute and late responding normal tissues. The linear quadratic model derived from radiobiological cell survival curves and animal studies defines different repair factors for different normal tissues and tumours. Modifications to the linear quadratic equation have been proposed to incorporate time factor for repopulation. TDF and ERD models have been applied in this study to the data of patients with breast cancer