Bilateral breast carcinoma: clinical characteristics and its impact on survival

The higher incidence of breast cancer, the improvements in diagnosis and treatment, together with the growing life expectancy have brought about an increase in the number of patients at risk for bilateral breast carcinoma. The aim of this study is to describe the characteristics of patients suffering from bilateral breast carcinoma who underwent surgery at the Breast Pathology Service of the Buenos Aires British Hospital and to analyze impact on survival. Between January 1970 and May 2007, 4,085 cases of breast carcinoma in 3,864 patients were treated at the Breast Diseases Division of the Buenos Aires British Hospital. A retrospective study of 194 patients with bilateral breast carcinoma was carried out: 80 synchronous and 114 metachronous. In order to compare survival, a group of 2,237 patients with unilateral breast carcinoma who had undergone surgery was analyzed. The risk of developing a contralateral breast carcinoma was 0.9% per year, with an accumulated risk at 15 years of 12.75%. The 5-year survival was 85.9% for unilateral carcinomas, 94.6% for metachronous carcinoma, and 63.3% for synchronous carcinoma. The 15-year survival was 65.5% for unilateral carcinomas, 52.3% for metachronous, and 37.2% for synchronous. The incidence of bilateral carcinomas is low. Survival was worse in patients with metachronous carcinoma diagnosed within 5 years of the first malignancy. Survival in patients with metachronous carcinoma diagnosed after 5 years is similar to those with unilateral carcinoma. Synchronous carcinoma was associated to worse survival, being an independent risk factor for mortality.