Synchronous bilateral breast carcinoma (SBBC) is an uncommon presentation, and the management of patients with this disease is not well established.

In order to evaluate whether patients with early-stage SBBC could be safely and effectively treated with bilateral breast-conserving therapy (BCT), the authors retrospectively reviewed the records of 24 patients with clinical Stage I-II SBBC treated during the period 1977-1989 with bilateral BCT. SBBC was defined as bilateral invasive carcinomas diagnosed no more than 1 month apart. The median age at diagnosis was 56 years (range, 32-85 years), and the median follow-up for surviving patients was 95 months (range, 68-157 months). Pathology slides were available for review in 19 cases. Cosmetic results and complications after BCT were scored. Outcome was compared with that of 1314 patients with unilateral Stage I or II breast carcinoma, within the same age range, treated during the same time period.

There were no significant differences between the SBBC and unilateral groups in actuarial disease free survival (70% and 74%, respectively, at 5 years), overall survival (88% and 87%, respectively, at 5 years), or crude distribution of sites of first failure. Multivariate analysis of overall survival and disease free survival also did not show bilaterality to be a significant factor. The cosmetic results for the SBBC group were not significantly different from those for the unilateral group. Physician assessment of cosmetic outcome was excellent in 57% and good in 43% of SBBC patients evaluated 25-48 months after BCT. Long term complications were rare in both groups.

Patients with early-stage SBBC can be safely treated with carefully planned, bilateral BCT, with outcome that appears to be comparable to that of patients with early-stage unilateral breast carcinoma.