Multinucleation is an objective feature useful in the diagnosis of pleomorphic lobular carcinoma in situ

Abstract

Objectives: Bi- and multinucleated (B/M) cells are present in a variety of tumors. We evaluated lobular carcinoma in situ (classic and pleomorphic types) and ductal carcinoma in situ (DCIS) to determine if this objective morphologic feature aids the differential diagnosis. Methods: The number of B/M cells was recorded in pleomorphic lobular carcinoma in situ (PLCIS) (n = 20), classic lobular carcinoma in situ (CLCIS) (n = 26), and DCIS (n = 37). Results: Binucleated cells were significantly more frequent in PLCIS (100%) vs DCIS (43%; P