成人仙尾部奇形腫の1例

Abstract

55歳男.人間ドックで骨盤内腫瘤, 左水腎症を指摘された.CTで仙骨前面に接し骨盤内臓器を腹側に圧排する13×11×15cmの腫瘤を認め, 内容は嚢胞成分, 脂肪織, 石灰化等が混在していた.手術は, まず砕石位で下腹部正中切開から経腹膜的に直腸後方の腫瘍に到達した.その際, 右総腸骨動脈部に右萎縮精巣を認め, 摘除した.腫瘤と直腸との間の剥離を進めると, 腫瘍は仙骨前面の一部と強く癒着していた.経仙骨アプローチを加えることとし, 体位をJack knife positionに変え, 仙骨後方に逆Y字切開した.S4, S5神経, 尾骨神経根を結紮切断した後, S4以下の仙骨, 尾骨を切断し腫瘍後面に到達した.鈍的に剥離を進めたが, S3仙骨と腫瘍との間に強い癒着を認めた.一部嚢胞壁が残存し嚢胞内容がこぼれたが, 腫瘍を一塊に摘出した.組織学的には悪性所見を認めず, 良性の成熟奇形腫と診断した.術後排便障害は1ヵ月で軽快し, 尿閉を術直後に認めたが, 1年後には自尿1回200mlと回復した

We report a case of adult sacrococcygeal teratoma resected by an abdominosacral approach. A cystic mass 13 cm in diameter in the pelvic cavity and left hydronephrosis were detected incidentally by abdominal computed tomographic (CT) scan in a 55-year-old man. The pelvic tumor extending from the presacral area to the coccyx was resected via a combined abdominal and transsacral approach. The resected specimen weighed 700 g and the pathological diagnosis was mature teratoma. While the sacrococcygeal area is the most frequent site of teratoma in infants, it is a rare site in adults. This is to our knowledge, the 30th case report of adult sacrococcygeal teratoma in Japan. At one month after the operation the patient had no bowel dysfunction and no dysbasia, but he had mild bladder dysfunction requiring self-catheterization twice a day at twelve months. The patient had no evidence of disease at twenty months after the operation.