Brain metastases in breast cancer patients receiving adjuvant chemotherapy.

A retrospective analysis was performed comparing the incidence of brain metastases as a site of first recurrence in patients receiving adjuvant chemotherapy during the period from 1973--1979 for node-positive operable carcinoma of the breast, compared to a matched control group of patients presenting during the same period treated by local measures only. Five of 115 patients (4.3%) receiving adjuvant chemotherapy have had brain metastases as first site of distant recurrence compared to zero of 115 (0%) in the control group. This comprised 12.8% of first distant recurrences in the adjuvant group. The authors suggest that this increased incidence of brain metastases, as site of first recurrence, reflects prolonged suppression of systemic disease by adjuvant chemotherapy with less effect in controlling metastases in the brain.