大腸癌および前癌病変の多発をみた潰瘍性大腸炎の1剖検例

Ulcerative Colitis Complicated with two Colonic Carcinomas and Precarcinomatous Lesions, an Autopsy Case

　潰瘍性大腸炎の長期罹患者の癌化率は一般人と比較し5～10倍高いと言われる¹．前癌病変に関する病理組織学的検討は，欧米ではYeomans²以後，多くの報告をみる．本邦でも潰瘍性大腸炎に合併する癌の報告例はあるが前癌病変に関する記載は極めて少ない³⁾⁴⁾．埼玉医大で，約15年の潰瘍性大腸炎罹患歴を有すると思われる症例を剖検し，多発する大腸癌および前癌病変の合併を認めたので若干の文献的考察を加え報告する．

　This report is an autopsy case (a 48 year-old man) of longstanding ulcerative colitis (about 15 years) with two colonic invasive carcinomas and five patchy lesions of severe atypical epithelia. The distributions of the carcinomas and the atypical colonic epithelia classified in three gradings were examined. The relationship between the carcinomas and atypical epithelia is discussed. Ulcerative colitis involving the rectum up to the terminal ileum was complicated with two carcinomas. One was an ulcerated type in the ileocecum, up to 9cm in the greatest dimension, and was microscopically proved to be poorly differentiated adenocarcinoma infiltratively proliferated in the colonic wall to the ornentum. The other was an elevated type in the proximal descending colon, up to 3.5 cm in the greatest dimension. It was microscopically well differentiated adenocarcinoma infiltrating the serosa. The atypical epithelia were extensively distributed and involved the mucosa away from the carcinomas as well as that in the immediate vicinity of them. Each of five patchy lesions of severe atypical epithelia was situated in the ileocecum, ascending colon, proximal and distal transverse colon and proximal descending colon, respectively. Macroscopic appearances of the atypical epithelia were velvety, villous, fine and rough granular and polypoicl. It was difiicult to distinguish severe atypical epithelia from mild or moderate one.

　Microscopically the atypical epithelia showed adenoInatous change, basal cell change and regenerated mucosal epithelium-like change, each of which had some relation to the severe atypical epithelia and it was difficult to differentiate the portion of the lesion from carcinoma in situ. In this case, some intimate relation between the carcinoma and the atypical epithelium was suspected. It is probably valid that the severe atypical epithelium may be considered precarcinomatous, but it was not evident that mild and moderate atypical epithelia may become severe type, though there could be such possibility. Successive colonoscopic and histological examination of ulcerative colitis will reveal true precarcinomatous lesions more exactly.