A case-control study of unilateral and bilateral breast carcinoma patients

BACKGROUND. Women with unilateral breast carcinoma are at increased risk fo r developing contralateral disease. The clinical significance of bilateral breast carcinoma has not been fully defined, and the subset of patients who may benefit from medical or surgical risk-reduction intervention has not y et been characterized. The purpose of this study was to evaluate risk facto rs and outcomes for bilateral breast carcinoma. METHODS, A subject group of 70 bilateral breast carcinoma patients (62% met achronous) was matched by age and survival interval with a control group of 70 unilateral breast carcinoma patients. Median follow-up was 103 months. RESULTS. Eighty-two percent of the unilateral patients and 80% of the bilat eral patients had Stage I or II disease at diagnosis. Median age at present ation was 53 years. In the bilateral group, the contralateral cancer was di agnosed at the same or earlier stage than the first cancer in 87% of cases. Bilateral patients were significantly more likely to have multicentric dis ease and to have a positive family history for breast carcinoma compared wi th the unilateral group. There were no significant differences regarding hi story of exogenous hormone exposure, lobular histology, hormone-receptor st atus, or HER-2/neu expression. Five-year disease-free survival was 94% for the unilateral breast carcinoma patients and 91% for the bilateral breast c arcinoma patients (P = 0.16). CONCLUSIONS. Survival for patients with bilateral breast carcinoma is simil ar to that of patients with unilateral disease; however, prophylactic risk- reduction intervention for the contralateral breast should be considered in patients who have multicentric unilateral disease or a positive family his tory for breast carcinoma. (C) 2001 American Cancer Society.