Robotic Laparoscopy and Endoscopy Cooperative Surgery for Primary Appendiceal Mucinous Carcinoma Masquerading as Bladder Cancer: A Case Report

Bladder invasion by appendiceal cancer resulting in a vesico-appendiceal fistula is an uncommon occurrence. Both radical tumor removal and functional preservation of the bladder are desirable in the surgical treatment of this disease, and there are few reports on detailed surgical methods. Here, we describe a case of primary appendiceal mucinous carcinoma with bladder invasion treated with robotic laparoscopy and endoscopy cooperative surgery (RECS). A woman in her 60s was initially considered to be bladder tumor and underwent transurethral resection. However, the tumor rapidly regrew, and she was rediagnosed with primary appendiceal cancer invading the bladder. RECS was performed, involving ileocecal resection with partial cystectomy. The postoperative course was favorable, with no bladder anastomotic leakage or ureteral obstruction. In the RECS procedure, the robotic operability facilitates bladder wall repair, and simultaneous cystoscopic observation allows for identification of the ureteral orifices, making the combined bladder resection radical and safe.