Appendiceal mucinous cystadenocarcinoma with implantation metastasis to the incision scar and cutaneous fistula.

Introduction: Mucinous cystadenocarcinoma of the appendix with invasion of the anterior abdominal wall and cutaneous fistula development is a rare condition. To the best of the authors' knowledge, five such cases have been reported in the medical literature.

Methods And Results: The patient was a 68-year-old man who presented with a mass growing through the incisional scar and a skin fistula with mucinous discharge 1 year after appendectomy via McBurney's incision. Carcinoembroyonic antigen and carbohydrate antigen 19-9 concentration was elevated. Abdominal computed tomography scan revealed a mass in the cecum with involvement of the abdominal wall. Right hemicolectomy with en bloc abdominal wall implant and skin fistula resection with clear margins was performed.

Discussion: The patient received intraperitoneal intra- and postoperative chemotherapy. Gross examination of the specimen showed a mass emerging from the remnant stump of the appendix. The patient showed no relapse 1 year after surgery. Clinical, paraclinical features, and treatment options are discussed with review of the literature.