Crohn病の癌化例の検討

A Study of Cancerization in Patients with Crohn's Diseases

要旨　過去12年間に当センターで経験したCrohn病の癌化例は小腸癌と直腸癌の異時性癌1例，直腸癌1例，痔瘻癌3例の5例6病変であった．それらの癌化例をもとに臨床病理学的特徴，癌化の発生形式，治療上の注意点を検討した．癌発見時の平均年齢は35歳，Crohn病の病脳期間は14.8年であり，病理組織学的所見では粘液癌5病変，中分化腺癌1病変であった．癌化の発生形式を①びまん性びらん病変からの癌化，②瘻管病変からの癌化，③common cancerに分類した．①のびまん性びらん病変からの癌化は潰瘍性大腸炎のcolitic cancerと同様な発生機序であると考えられた．また狭窄病変の口側や小腸の検索は困難なため，全例に有効なsurveillanceを行うことはできないであろうが，10年以上のCrohn病罹患歴の患者にはできる限り癌を念頭に置いた検索が必要である．特にびまん性のびらん病変や瘻孔病変を有する患者には注意を要する．

　Over a period 12 years we experienced 5 patients including each one patient of metachronal colon or rectal cancer, 3 carcinomas of anal fistula, totally with 6 lesions, showing cancerization from Crohn's disease. The present study assessed clinicopathologic features, modality of cancerization, and risk factors for treatment. At the time of diagnosing a cancerization, mean patient age was 35 years, mean duration of Crohn's disease was 14.8 years, and histopathological findings included 5 lesions of mucinous carcinoma and one lesion of moderately differentiated adenocarcinoma. The cancerization modalities were classified as from 1) diffuse and erosive lesions, 2) fistulous lesions, and 3) common cancers. Cancerization of 1) supposedly had a similar developmental mechanism as that of colitic cancer from ulcerative colitis. Although lesions at the aboral site of contraction and of the small intestine are difficult to detect resulting in limited cases for effective surveillance of cancerization, we believe that patients with a longer than 10 year history of Crohn's disease should be examined for possible cancerization. Especially patients with diffuse and erosive as well as fistulous lesions should be examined closely for cancerization.