潰瘍性大腸炎のサーベイランス・スタディー

Surveillance Study on Cancer and Dysplasia Associated with Ulcerative Colitis

要旨　長期経過した潰瘍性大腸炎（UC）患者に対しdysplasiaの発見を目的とした内視鏡検査（surveillance colonofiberscopy：SCF）を行い大腸癌のリスクの評価を行った．1979年より1990年までに90例のUC患者に対し261回のSCFを行った．そのうち全大腸炎型63例（残存直腸型19例）から癌 3，dysplasia: high-grade 2，low-grade 4，indefinite 9，左側型27例からlowgrade 1，indefinite 1例を認めた．indefiniteを含めたdysplasiaの合併頻度は22％であり欧米からの報告に匹敵した．癌3例はすべてDukes Aであり，術後の平均追跡は3年で生存中である．核DNA量の解析によりdysplasiaの診断精度は上昇した．UCに合併する癌，dysplasiaの早期発見にはSCFは有効と考えられた．

　Surveillance colonoscopy has been performed to detect dysplasia and surgically treatable carcinoma in patients with ulcerative colitis. A total of 261 surveillance colonoscopies were carried out in 90 patients with longstanding ulcerative colitis of total or left sided type between 1979 and 1990. Out of 63 patients with total colitis, including 19 with rectal stump who had undergone colectomy and ileo-rectal anastomosis, 3 had carcinoma, 2 high-grade dysplasia, 4 low-grade and 9 indefinite for dysplasia. Out of 27 patients with left sided colitis, one had low-grade dysplasia and another one indefinite for dysplasia. The overall incidence of dysplasia including indefinite cases was 22%, similar to the reported incidence from western countries. All these patients who had carcinoma are alive and well postoperatively during 3-year period of follow-up. Microspectrophotometric DNA measurement has proved useful in diagnosing dysplasia associated with ulcerative colitis. Surveillance colonoscopy is useful in selecting patients at high risk of carcinoma at curative stage.