Mucinous appendiceal adenocarcinoma invading the bladder: not always an easy diagnosis. A case report.

Appendiceal neoplasms account for less than 1% of intestinal cancers and their clinical manifestation is typically, nonspecific and ambiguous. Appendiceal tumor infiltrating the urinary tract is extremely rare and few cases are mentioned in literature. A 72-year-old woman presented gross hematuria and right colic pain. No prior urologic disease was reported. Cystoscopic examination showed a large lesion on the right side of posterior bladder wall, with multiple ulcerated areas and microscopical examination of the specimen revealed a mucinous adenocarcinoma infiltrating urinary bladder. Contrast-enhanced computed tomography (CT) scan identified focal thickening of bladder dome 21 × 7 cm with a possible origin from the appendix and with an unclear relationship with the uterus and the right fallopian tube. These findings were discussed with the local gastrointestinal multidisciplinary team, where a decision to perform upfront surgery was made. Explorative laparotomy confirmed a tumor of the appendix invading the urinary bladder. We performed an en-bloc resection including right colon, 40 cm of terminal ileum with a partial cystectomy removing the infiltrated area of the right bladder wall, and an omentectomy. Reconstruction was made first with a full-thickness suture of the bladder, then with an ileo-colon stapled anastomosis. The postoperative course was uneventful and the CT scan at 9 months from surgery did not show any recurrence. Right hemicolectomy is considered the gold standard for all lesions with invasion beyond the mucosa, and, appendicectomy alone seems to be the ideal treatment for in situ and localized cases.