Scrotal leiomyomas with bizarre nuclei: a report of three cases.

We discuss here three cases of scrotal leiomyoma with bizarre nuclei. The patients, ranging in age from 44 to 58 years, presented with painless scrotal masses that were clinically diagnosed as cysts. Clinical follow-up, available for two of the patients, revealed no evidence of local recurrence or distant metastasis 5 years after resection. The tumors were well circumscribed and ranged from 2 to 3 cm in maximal diameter. They were characterized by interlacing fascicles of spindle-shaped cells with pleomorphic nuclei. Nuclei were large and multilobulated with hyperchromatic chromatin and macronucleoli. Multinucleated tumor cells were infrequent. Intranuclear invagination of eosinophilic globules of cytoplasm produced pseudonucleoli. There was no mitotic activity. Immunohistochemically, the tumor cells expressed vimentin, desmin, smooth muscle actin, and muscle-specific actin, but not cytokeratin, neurofilament, or glial fibrillary acidic protein. In contrast to scrotal leiomyosarcomas, scrotal leiomyomas with bizarre nuclei are not hypercellular, and they lack mitotic activity.