Leiomyoma of the urethra in a Mexican woman: a rare neoplasm associated with the expression of estrogen receptors by immunohistochemistry.

BACKGROUND: Leiomyoma of the female urethra is a rare condition, although it can occur anywhere along the genitourinary tract. METHODS: We report on a 22-year-old woman found to have a urethral mass detected in our hospital delivery room. Examination showed a 6 X 5-cm mass at the urethral meatus. RESULTS: Pathologic examination revealed urethral leiomyoma. Immunohistochemistry confirmed leiomyoma with positive staining for vimentin, desmin, and actin. Immunoreactivity for estrogen receptors was also detected. CONCLUSIONS: Because this lesion was discovered while the patient was pregnant and it showed immunoreactivity for estrogen receptors, it is suggested that increased estrogen levels could accelerate smooth muscle growth.