Invasive lobular carcinoma of the male breast: a case report.

A case of lobular carcinoma in a male breast is described. Because the structure of the male breast does not have lobules and acini, lobular carcinoma cases are seen infrequently. The pathological diagnosis was invasive lobular carcinoma of the breast. The karyotype of the patient revealed a 46 XY/46 XY, dmin (double minutes) chromosomal structure. Although 28% of the examined metaphases showed 46 XY, 1-5 dmin, the others were normal. We reviewed the English literature and found 20 reported cases of lobular carcinoma of the male breast. Our case represents lobular carcinoma in a proven genotypic male patient showing no exogenous or endogenous estrogens.