Radiotherapy after breast-conserving surgery in small breast carcinoma: Long-term results of a randomized trial

Background: Breast-conserving surgery followed by radiotherapy is a widely accepted form of treatment in patients with breast cancer of limited extent . Many attempts have been made to identify subgroups of patients who might avoid radiotherapy. Patients and methods: Between 1987 and 1989, 579 women with carcinoma of th e breast were randomly assigned to quadrantectomy, axillary dissection and radiotherapy (299) and to quadrantectomy with axillary dissection without r adiotherapy (280). Eligible patients were women with a breast carcinoma les s than 2.5 cm in maximum diameter up to 70 years of age. Primary endpoints were intra-breast tumour reappearance (IBTR) and all-cause mortality. Results: The number of IBTRs was significantly higher in patients treated w ith surgery alone (59 cases out of 273; 10-year crude cumulative incidence of 23.5%) than in patients treated with surgery plus radiotherapy (16 cases out of 294; 10-year crude cumulative incidence of 5.8%). The difference in IBTR frequency between the two treatments appeared to be particularly high in women up to 45 years of age, tending to decrease with increasing age up to no apparent difference in women older than 65 years. Overall survival c urves for the two groups, did not differ significantly (P = 0.326). However , a limited survival advantage was evident after radiotherapy for node-posi tive women. Conclusions: After breast-conserving surgery radiotherapy appears indicated in all patients up to 55 years of age, in patients with positive axillary nodes, and in patients with extensive intraductal component at histology. T he data suggest that radiotherapy may be avoided in patients older than 65, and may be optional in women aged 56-65 years with negative nodes.