Figure 1.

Estimated tumour log cell kill plotted vs tumour cell doubling time Tp during radiotherapy of the four schedules in the Radiation Therapy Oncology Group 90-03 clinical trial [27, 28]. The start of repopulation Tk was assumed to be 21 days. The rapid decrease of tumour effect as doubling time decreases is obvious, with two pairs of the schedules predicted to give identical results at two different levels of cell kill, but both at Tp = 2 days only, at the crossover points. Redrawn from log cell kill Figure 7 of Fowler 1989 [1].