家族性大腸腺腫症における長期経過からみた大腸病変の取り扱い

Management of the Colonic Lesions of Familial Adenomatous Polyposis from the Viewpoints of Long-term Follow-up

要旨　1966年11月から1996年10月までの約30年間に国立がんセンターを受診し，家族性大腸腺腫症と診断され，経過観察が行われたのは78症例であった．56例に大腸の切除術がなされ，22例に結腸全摘回腸直吻合術が施行された．このうち3年以上の経過観察がなされた16例中7例で，残存した直腸に癌が出現し，初回手術から2回目手術までの平均follow-up年数は13.6年であった．この7例中3例に進行癌が出現したが，いずれも定期的な外来通院を中断し，長期間経過観察を受けていない症例であった．一方，定期的な経過観察が行われた症例では，早期癌は認められても進行癌の出現はなかった．これらの結果から，結腸全摘回腸直腸吻合術を行った症例では，放置すると10年以内に，進行癌が出現する危険性が高いことが判明し，直腸を温存した術式では，少なくとも年1回の経過観察の必要性が再確認された．

　During the period of 30 years between November 1996 and October 1996, 78 cases of familial adenomatous polyposis were diagnosed and followed in the National Cancer Center Hospital. Fifty six cases underwent colectomy, 22 of them were treated by the total colectomy with ileo-rectal anastomosis (IRA). Eight out of 17 cases treated by IRA and followed more than three years developed cancer in the residual rectum. The average follow-up period between the initial and second operations was 13.7 years. Three out of eight cases developed advanced cancers, but all of them missed regular follow-up visits and did not receive adequate evaluation over a long period of time. On the other hand, those who received regular follow-up examinations did not develop advanced cancer but early cancer. These results suggest that FAP patients treated by IRA may develop advanced cancer within 10 years if not followed properly, therefore those who underwent the operation for FAP which preserved the rectum should be evaluated at least once a year.