Synchronous and Metachronous Bilateral Breast Malignancies: Report of Two Cases and Literature Review

Abstract

Abstract Background: Bilateral breast cancer (BBC) is a rare event accounting for 1%–3.2% of all breast malignancies. A second tumor in the contralateral breast may be either a synchronous or a metachronous lesion. The tumor is defined as a synchronous breast carcinoma (SBC) when contralateral cancer is identified within 6 months after the first breast cancer and as a metachronous breast carcinoma (MBC) if identified after 6 months. The majority of bilateral breast cancers are MBC, while SBC, accounts for 0.2%–2% of bilateral breast cancers. Cases: This article presents 1 case each of synchronous and metachronous BBC and discusses their distinct characteristics and varying concepts. Conclusions: As the prognosis of BBC is poor, it is crucial to be aware of this entity, and every patient with breast cancer should be followed-up regularly. (J GYNECOL SURG 32:136)