潰瘍性大腸炎関連腫瘍に対する外科治療の現状と課題

Current Status and Issues Related to Surgical Treatment for Ulcerative Colitis-associated Colorectal Cancer

要旨●潰瘍性大腸炎に合併する癌/dysplasiaで手術となる症例が著明に増加している．ただ，サーベイランス内視鏡検査の技術の向上に伴い，比較的早期に診断される症例が増加している．そのため病理組織学的には，高分化型腺癌が最も多い組織型であり，予後も比較的良好で，累積5年生存率は約90%である．外科的問題点としては潰瘍性大腸炎に合併する大腸癌症例は比較的栄養状態の良好な症例に多く，肥満体型の症例ではJ-pouchが肛門まで届かない症例が増加していることである．また，今後の問題点としては，難治性回腸囊炎症例のpouch内の発癌についても注意する必要がある．大腸の部分切除や内視鏡的治療は症例を慎重に選ばなければならない．

　Because of improved surveillance colonoscopy techniques, the number of patients with cancer or dysplasia complicated with ulcerative colitis who undergo surgical treatment is increasing, as patients are more routinely diagnosed at a relatively early stage. Thus, well-differentiated adenocarcinoma is the most common histologic type. The prognosis of affected patients is relatively good, with a cumulative 5-year survival rate of approximately 90%. Surgical problems are often encountered in colitic cancer patients who are overweight or obese, with an increased number of patients in which the J-pouch does not reach the anus. Additionally, as a potential future complication, care is necessary regarding cancer in the pouch in refractory cases of pouchitis. In such patients, partial resection of the large intestine and endoscopic treatment should be carefully selected.