Radiotherapy with and without chemotherapy after breast conservation surgery for early stage breast cancer: a review of timing

Purpose: To evaluate the effects in women of the timing of breast irradiation (BI) in relation to the application or non-application of adjuvant chemotherapy after breast conservation surgery (BCS) for early stage cancer. Methods: Between October 1981 and June 1995, 47 women with stage I and II breast cancer underwent BCS. Twenty-six patients did not receive adjuvant chemotherapy (NAC) and 21 women did (AC). In the NAC group, BI commenced within (n=9) or after (n=17) seven weeks following BCS; in the AC group, 18 women received BI more than 24 weeks after BCS and three patients within 24 weeks. Results: In the NAC group, there was a trend toward more local and systemic failures plus a definite correlation with poorer survival (p=0.05) when BI was initiated more than 7 weeks after BCS. In the AC group, the locoregional and systemic failures occurred only in women with a delay of BI exceeding 24 weeks; survival was not different between the subgroups. Conclusion: An undue delay of BI should be avoided in patients after BCS whether they require adjuvant chemotherapy for early stage breast cancer or not.