Selective avoidance of postoperative locoregional radiotherapy in breast cancer seems to be justified.

OBJECTIVE: To try and reduce the amount of routine postoperative radiotherapy that we prescribed without causing an unacceptable rise in locoregional recurrences. DESIGN: Retrospective study. SETTING: Teaching hospital, The Netherlands. SUBJECTS: 836 women who were treated for breast cancer between January 1980 and December 1989. INTERVENTIONS: These 836 had been treated by modified radical mastectomy (n = 534), excision of the tumour and axillary dissection (n = 279), lumpectomy (n = 15), or total mastectomy (n = 8). In December 1984 we stopped giving routine postoperative irradiation to women with T1 or T2 tumours unless there was any doubt about the operative specimen. MAIN OUTCOME MEASURES: The rate of locoregional recurrence 1985-9 compared with that from 1980-December 1984. RESULTS: Only 1 patient of 836 had a clinically detectable recurrence in the internal mammary chain. There were only 2 recurrences in the 235 axillas that had not been irradiated. CONCLUSION: By a process of careful selection of patients for locoregional irradiation, the number of fields of irradiation given to patients with breast cancer can be reduced by up to 80% without causing a rise in the rate of locoregional recurrences.