Secretory carcinoma of breast with EGFR and weak ER positivity: A case report with discussion of distinguishing features

Abstract

Secretory breast carcinoma (SBC) is a rare histologic type of indolent carcinoma breast, accounting for <0.5% of all breast cancers. It is characterized by intracellular or extracellular secretion and granular eosinophilic cytoplasm of the neoplastic cells. A 46-year-old woman presenting with palpable breast lump, was diagnosed as Secretory carcinoma following imaging and preoperative core-needle biopsy. Patient underwent neoadjuvant chemotherapy, followed by breast conserving surgery. The diagnosis was further confirmed on histopathology and Immunohistochemistry (IHC) with weak ER positive and EGFR positive tumour showing no expression of PR, Her2neu and CK5/6. Secretory carcinoma is a rare and special type of invasive breast carcinoma, with a wide age range and good prognosis. Inclusion of both basal markers (CK5/6,EGFR) on IHC and cytogenetic analysis are crucial for confirmation of SBC.