Familial adenomatous polyposis (FAP) is a hereditary disease characterized by the appearance of numerous polyps in the large bowel with a high potential for malignant transformation unless untreated. A variety of extracolonic manifestations were reported such as osteoma, epidermoid cyst, desmoid tumor, gastroduodenal polyps, small bowel tumor, congenital hypertrophy of the retinal pigment epithelium, hepatobiliary tumor, thyroid tumor, and tumor of 12 the central nervous system. However, the ovarian involvement of FAP as an extracolonic manifestation was very rare and there have been only few reports. We experienced a rare case of ovarian cystadenofibroma in a patient with FAP as an extracolonic manifestation. We also found colon cancer with multiple hepatic metastasis initially manifested as intestinal obstruction in the same patient. Surgical treatment and subsequent chemotherapy for colon cancer and intraoperative radiofrequency ablation of hepatic metastasis were 15 performed.ope
