Carcinoid tumor in the female urethral orifice: rare case report and a review of the literature.

We experienced an extremely rare tumor in the female urethral orifice in a 57-year-old Japanese woman. To our knowledge, only two cases of primary urethral carcinoid tumor have been reported. The previous reports of urethral carcinoid tumor were recognized in the male middle urethra and penile urethra. The present case was resected, and diagnosed as a carcinoid tumor by histological, immunohistochemical and ultrastructural findings. The tumor cells were stained by chromogranin A, synaptophsin and neuron-specific enolase, and neurosecretory granules were confirmed with electron microscopy. The patient did not complain of any symptoms until 5 years after the resection of the tumor. Therefore, the case we describe here is the first known report of carcinoid tumor in the Japanese female urethra.