本邦の報告例からみた腸結核関連大腸癌―萎縮瘢痕帯は高い発癌のポテンシャルを有するのか?

Clinicopathological Features of Intestinal Tuberculosis-related Carcinoma: A Review of the Reported Cases in Japan

要旨　大腸結核に侵された領域内にみられた大腸癌―大腸結核関連大腸癌―の61論文を解析し，以下の成績を得た．(1)病歴，胸写：肺結核などの既往を有する21例では，20例が9～59年前に罹患，治療された病歴を有していた．大腸結核と確診された14年および19年後に腸結核関連大腸癌が発生した2症例がみられた．(2)腸結核関連大腸癌の95％は右側結腸にみられた．(3)肉眼型：2型癌は2例（3.3％）のみ，粘液癌または粘液成分を有するものは42.6％にみられた．(4)癌巣以外の活動性潰瘍は23.0％にみられたにすぎなかった．線維症も萎縮瘢痕帯もなしと記載されたものは1例のみであった．(5)腺腫または異型上皮巣合併例は27.9％であった．萎縮瘢痕帯からの癌化と判断される3報告例がみられた．上記成績に考察を加え，腸結核の萎縮瘢痕帯は癌化のポテンシャルを高めると推測した．

　Introduction:

　In Japan, so-called “scarred area” has been a characteristic finding for healed interstianal tuberculosis in double-contrast radiology and endoscopy. In order to investigate whether this “scarred” area has a potential risk for carcinogenesis, we reviewed 61 cases with intestinal tuberculosis-related carcinomas that arose within the scarred area.

　Results: 　1. Twenty-two of the 61 cases had medical histories of extra-intestinal tuberculosis. The duration between the episodes of extra-intestinal tuberculosis and the development of carcinoma was 9 to 59 years.

　2. The male to female ratio was 0.19. The mean age (SD) was 61.8 (10.4) years old, which was significantly older than that of the reported age of onset for intestinal tuberculosis in Japan.

　3. Ninety-five percent of the carcinomas were located in the right hemicolon.

　4. Pathologically, only 5.0% of the carcinomas revealed ulcerative expansive type in their macroscopic appearance and 42.6% of them showed mucinous components in their histological findings.

　5. 98.4% of cases depicted fibrosis in the submucosal layer around the carcinomas.

　6. Co-existing dysplasia was found in 27.9% of cases. In three cases, histopathological investigation indicated multiple carcinomatous foci with various grades of dysplasia within the scarred area as well as the main carcinoma.

　In conclusion, it was suggested that the scarred area might have some potential to develop carcinoma.