Bilateral synchronous breast cancer: Mode of detection and comparison of histologic features between the 2 breasts

Background. Bilateral synchronous breast cancer is uncommon (accounting for 1.0 %-2.6 % of all patients with breast cancer), and most physicians do no t accumulate a large personal experience of patients with this disease. We reviewed our experience with patients with bilateral synchronous breast can cer, focusing on the mode of detection and histologic features in the 2 bre asts. Methods. The charts of patients who were treated at this institution for bi lateral synchronous breast cancer during the 15-year period of 1984 through 1999 were reviewed. Information regarding age, mode of detection, histopat hologic features, treatment, and overall survival were analyzed. Results. During the study period 51 patients (all women) were treated at ou r institution for bilateral synchronous breast cancer This comprised 2.1 % of all patients (n = 2382 patients) treated for breast cancer during the sa me period of time. The first cancer was detected by palpation in 81 % and b y mammography in 14%. The corresponding figures for the contralateral cance r were 24 % and 54 %, respectively. The histologic type of cancer was ident ical in the 2 breasts in 29 patients (57 %) and tons different between the 2 breasts in 22 patients (43 %). The overall 10-year survival rate was 63 % . Conclusions. Bilateral synchronous breast cancer is often detected by mammo graphy and is frequently of the same histologic type as the index cancer A better awareness of the risk for this disease may help detect bilateral bre ast cancer earlier.