Mesonephric adenocarcinoma of the urinary bladder: a case report.

We report a very rare case of mesonephric adenocarcinoma of the urinary bladder, the origin of which is still uncertain. A non-papillary and broad-based tumor was located in the trigone and bladder neck on cystoscopic examination. Pelvic magnetic resonance imaging in T2-weighted images revealed a mass invading into the muscular layer of the bladder wall. Histologic examination of bladder cup-biopsy specimens showed adenocarcinoma. She underwent total cystectomy and pelvic lymph node dissection. Histologically, the tumor was chiefly composed of cells with eosinophilic cytoplasm and partly of cells with clear cytoplasm or hobnail-shaped cells, arranged in tubular or papillary structures, and infiltrated peri-vesical fat tissues. She died of metastatic disease 22 months after surgery. To the best of our knowledge, the present case is the 19th reported in the literature.