Invasive Lobular Carcinoma of Breast with Extracellular Mucin: A Novel Entity

Abstract

Invasive carcinoma of no special type (NST) or ductal carcinoma is the most common type of invasive breast cancers. Invasive lobular carcinoma (ILC) is the most common special variant amongst breast cancers that lacks some of the common features associated with breast cancers e.g. absence of desmoplastic reaction and infrequent mitosis. Some cases of ILC produce intracellular mucin that pushes the nucleus to one side, creating the characteristic signet ring cell morphology. Extracellular mucin secretion is essentially described in association with mucinous breast carcinoma and ductal carcinoma. Very few cases of ILC showing extracellular mucin has been reported in literature. Herein, such a rare case of classic lobular carcinoma is described, in a 70-year-old female who presented to the Surgical department of our hospital. Keywords: Breast cancer, Extracellular mucin, Invasive lobular carcinoma