Mucinous Adenocarcinoma and Carcinoid Tumor Arising Within an Ovarian Mature Cystic Teratoma: A Case Report.

The coexistence of both mucinous adenocarcinoma and carcinoid tumor within an ovarian mature cystic teratoma is extremely rare. We report a case of an 18-year-old Omani woman with a left ovarian cyst. After laparotomy with left salpingo-oophorectomy, omentectomy, and peritoneal washings, the excised cyst had the typical morphology of mature cystic teratoma with grade I mucinous adenocarcinoma and a focus of carcinoid tumor.