CHART

Michele Saunders and Stanley Dische reasoned that tumour cells repopulate during a conventional six-week radiotherapy course, so they built a schedule that gave the whole dose in twelve consecutive days, three fractions a day, weekends included. The trial entered 563 patients through 13 centres and randomised them 3 to 2 to CHART or conventional radiotherapy.

CHART reduced the relative risk of death by 24 percent, lifting two-year survival from 20 percent to 29 percent (p = 0.004). In squamous cell carcinoma, which was 82 percent of the trial, the reduction was 34 percent and two-year survival went from 19 percent to 33 percent. Severe dysphagia in the first three months was commoner with CHART (19 percent against 3 percent) but there was no important difference in other morbidity. The mature analysis confirmed a 22 percent reduction in the relative risk of death and a 21 percent reduction in local progression, and found a 24 percent reduction in the relative risk of metastasis, which the authors read as evidence that better local control prevents spread. The schedule was logistically hard for departments to run, and the UK kept iterating on it with CHART-ED and INCH.