Primary adenocarcinoma of the female urethra with three histologic patterns and partial AFP positivity.

A rare case of adenocarcinoma of the female urethra with alpha-fetoprotein (AFP) positivity in a 52-year-old woman is reported. The tumor was papillary polypoid, localized in the posterior wall of the mid-urethra and microscopically showed three histologic components. Upon immunostaining and histochemical staining, the tumor was characterized by intestinal-type cells positive for epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA), EMA-negative and AFP-positive columnar vacuolated cells and mainly EMA-positive clear cells. On the basis of these features together with the known embryogenesis of the urethra, an endodermal origin of the tumor is suggested, possibly arising from the reserve or stem cells in the urethral mucosa. This case and its immunohistochemical features are quite unique and the histologic combination is meaningful when considering the oncogenesis and histogenesis of urethral tumors.