Sequencing of chemotherapy and radiation in lymph node-negative breast cancer.

Purpose: To conduct a retrospective analysis of chemotherapy and radiation sequencing in lymph node-negative breast cancer patients treated with breast-conserving surgery.

Patients and methods: Between February 1982 and January 1996, 124 patients with lymph node-negative breast cancer underwent breast-conserving surgery with axillary dissection followed by chemotherapy and radiation therapy. The outcome of 68 patients who received chemotherapy first was compared with that of 56 patients who received radiation first. The two groups were balanced with respect to patient age, tumor stage, margin status, and estrogen and progesterone receptor status. Sixty-two percent of the patients had T1 primary disease. The median follow-up among surviving patients was 44 months for the chemotherapy-first group and 61 months for the radiation-first group.

Results: There were no statistically significant differences in local control, disease-free survival, or overall survival between the two groups. Five-year actuarial rates for local control for the chemotherapy-first and the radiation-first groups were 100% and 94%, respectively. Five-year recurrence-free rates for the chemotherapy-first and radiation-first groups were 92% and 77%, respectively. The 5-year overall survival rate was 89% for both groups.

Discussion: Giving chemotherapy before radiation in lymph node-negative breast cancer did not compromise local control. Given the concerns about increased distant metastases if radiation is given first, the chemotherapy-radiation sequence is recommended.