Mucinous Cystadenoma of the Urachal Remnant Successfully Resected by Laparoscopic Surgery: A Case Report.

A urachal remnant is a disorder resulting from a disturbance in the closure process of the urachus. A 55-year-old man was referred to our hospital for treatment of gallstones. The computed tomography scan revealed a cystic mass in the lower abdomen connecting to the urinary bladder. The preoperative diagnosis was a urachal cyst. Simultaneous laparoscopic cholecystectomy, mass resection, and urachectomy were performed. The mass on the cranial side of the urinary bladder was located on the median umbilical ligament. Both were resected and removed, along with the umbilicus. The postoperative course was uneventful. The histopathological diagnosis was urachal mucinous cystadenoma. There is no sign of a recurrence. A complete resection without damage is especially important for mucinous tumors of the urachal remnant because the injury to the tumor may lead to the development of pseudomyxoma peritonei. Only seven cases of mucinous cystadenoma of the urachal remnant were reported in English literature, and only one of these was treated with laparoscopic surgery. In our case, complete resection was possible by taking advantage of the magnifying effect of laparoscopic surgery. Furthermore, we are able to provide very clear intraoperative images and specimen photographs, which we believe will be useful for readers. Laparoscopic surgery will be beneficial when treating similar cases in the future. However, it should be kept in mind that a safe resection requires careful and meticulous technique.