Breast masses occur in men far less commonly than women and are infrequently subjected to fine-needle aspiration (FNA) biopsy. Papillary lesions of the male breast are rare and are comprised of a spectrum of lesions ranging from papillary hyperplasia in gynecomastia to invasive papillary carcinoma. The following study describes the cytomorphology of papillary breast lesions in 11 men. The patients ranged in age from 23 to 78 years old and each presented with an unilateral subareolar or periareolar breast mass that varied in size from 0.5 to 3 cm. Two patients presented with bloody nipple discharge.
Archival material (8-year period) from FNA biopsies of papillary lesions of the male breast was reviewed. The reviewed cases were correlated with appropriate clinicopathologic follow-up.
The smears had variable cellularity but all showed papillary clusters of mammary epithelial cells with and without fibrovascular cores. Single epithelial cells with a high nuclear-to-cytoplasmic ratio and eccentric nuclei were seen in all smears; however, these were more numerous in cases of adenocarcinoma. Hemosiderin-laden macrophages were present in all cases. Nipple discharge was seen only in the 2 benign lesions. All adenocarcinomas occurred in older men.
The only cytologic criteria that differentiated benign from malignant papillary lesions were marked cellularity and the presence of abundant 3-dimensional clusters. To the best of the authors' knowledge, the current series is the largest in the English literature to date that examines the cytomorphologic features of papillary breast lesions in men.