Guidelines for Complications of Cancer Treatment Vol VIII Part B

undertaken, based on individual patient data, of the relevantrandomised trials that began by 1995.METHODS: Information was available on 42,000 women in78 randomised treatment comparisons (radiotherapy vs noradiotherapy, 23,500; more vs less surgery, 9300; more surgeryvs radiotherapy, 9300). 24 types of local treatment comparisonwere identified. To help relate the effect on local(ie, locoregional) recurrence to that on breast cancer mortality,these were grouped according to whether or not the 5-yearlocal recurrence risk exceeded 10% (10%, 25,000 women).FINDINGS: About three-quarters of the eventual localrecurrence risk occurred during the first 5 years. In thecomparisons that involved little (10%) differences, however, 5-yearlocal recurrence risks were 7% active versus 26% control(absolute reduction 19%), and 15-year breast cancer mortalityrisks were 44.6% versus 49.5% (absolute reduction 5.0%, SE0.8, 2p