Tubular Carcinoma of the Breast: Immunohistochemical and DNA Flow Cytometric Profile.

Overview

Molecular markers of ordinary invasive ductal carcinoma of the breast have been extensively studied and their prognostic significance has been assessed. A common variant of breast cancer, tubular carcinoma, has an excellent prognosis as judged from several clinicopathologic studies. One would assume that tubular carcinomas have "favorable" molecular markers, however, published series of tubular carcinomas do not include molecular markers. We describe the molecular markers of 39 consecutive tubular carcinomas collected between January 1995 and July 1997. DNA ploidy, S-phase, estrogen and progesterone receptor (ER and PR, respectively) expression, and immunoreactivity for MIB-1, p53, and erbB2 were evaluated. Seventy-two percent of tubular carcinomas were DNA diploid, 49% had an S-phase less than 5%, 95% were ER positive, 69% were PR positive, 88% had less than 10% MIB-1-positive cells, 97% were p53 negative, and 97% did not overexpress erbB2 protein. Thus tubular carcinomas exhibit favorable molecular characteristics, which may play a role in their good prognosis.