Background: Lobular breast cancer in men is an extremely infrequent occurrence due to the lack of lobules and acini in the male breast. Such a rare case is described here. Case Report: A 74-year-old patient presented with a sizeable lesion in the right breast, which proved to be a lobular carcinoma. Genetic studies excluded Klinefelter’s syndrome, though revealing an interesting genetic multiformity feature. This case represented a lobular carcinoma in a genotypically male patient under no exogenous or endogenous estrogenic influence. Conclusions: The increasing number of male lobular breast cancer cases should be explored more extensively with particular emphasis placed on causally related genetic and hormonal factors.