家族性大腸腺腫症に伴う甲状腺癌の1例

Familial Adenomatous Polyposis Associated with Carcinoma of the Thyroid Gland, Report of a Case

要旨　家族性大腸腺腫症（familial adenomatous polyposis; FAP）に伴った甲状腺癌の1例を経験した．患者は21歳，女性．粘血便，頸部腫瘤を主訴とし，大腸に非密生型のポリポーシス，甲状腺に3個の腫瘤を認めた．甲状腺亜全摘術，頸部リンパ節郭清および結腸全切除術，回腸直腸吻合術を施行した．径10mm以上のポリープ13個はm癌12個，sm癌1個であった．甲状腺腫瘤はいずれも乳頭癌で，リンパ節転移を認めなかった．FAPでは甲状腺癌のリスクが高く，その特徴として若年で発症しやすく，組織型は乳頭癌で多発性であり，また大腸癌を合併する傾向にある．思春期以降のFAP女性患者では甲状腺の検査が必要である．

　We report a 21-year-old woman with familial adenomatous polyposis (FAP) associated with carcinoma of the thyroid gland. She had no family history of FAP. Palpation and ultrasonography examination of the neck revealed three well-defined masses in the thyroid. Colonoscopy showed sparse-type polyposis in the colon and rectum. She underwent subtotal thyroidectomy with modified neck dissection and total colectomy with ileo-rectal anastomosis. Histologic examination revealed three papillary carcinomas in the thyroid gland and early carcinomas in 13 colonic polyps of which the diameters were larger than 10 mm. A review of the Japanese literature reveals the following characteristics of thyroid carcinoma in FAP patients; female predominance, early onset in youth, papillary carcinoma with multicentricity and association of colon cancer. Regular examination of the thyroid gland including palpation and ultrasound examination should be part of the routine follow-up of female FAP patients from the age of puberty.