大腸villous tumorの診断―組織所見と切除標本肉眼所見，X線および内視鏡所見との比較を中心に

Diagnosis of Villous Tumors of the Colon: A Comparison of Histologic Findings with Macroscopic, Radiologic, or Endoscopic Features

要旨　villousあるいはtubulovillousと判定された大腸腫瘍46例47病変と，tubular adenoma9例10病変を合わせた57病変を対象とし，組織所見と切除標本肉眼所見，X線および内視鏡所見とを比較検討した．その結果，組織所見と切除標本肉眼所見の間に良好な相関性が認められた．すなわち，組織学的なvillous成分の増加と共に，腫瘍表面の絨毛状～顆粒状パターンが顕著となり，結節状パターンは減少した．また，X線および内視鏡所見も組織所見とよく相関し，組織学的なvillous成分の増加と共に，X線上の網目状～顆粒状パターンおよび隆起辺縁の毛羽立ちが，内視鏡上の微細顆粒状～絨毛状パターン，粘液付着および特徴的な色調（中等度ないし軽度の発赤を呈し，部分的に白色調を認める）がそれぞれ顕著となった．そして，これらvillous tumorに特徴的なX線・内視鏡所見は，組織学的なvillous成分が腫瘍全体の約3/4以上を占める症例（VおよびV＞T）で高頻度に出現した．したがって，villous tumorは，組織学的なvillous成分が腫瘍全体の約3/4以上を占めるものに限定されるべきであると考える．

　The purpose of the present investigation was to study the correlation between histologic findings and macroscopic, radiologic or endoscopic features of villous and tubulovillous tumors of the colon, and also to construct the definition of villous tumors of the colon. Based on histologic findings, 47lesions of villous or tubulovillous tumor and 10lesions of tubular adenom^a of the colon were divided into the following 6 groups:

　1) villous elements form more than 90 per cent of the whole tumor (V, 14lesions) ;

　2) villous elements form about 75 per cent (V＞T, 8lesions) ;

　3) villous elements form about 50 per cent (V＝T, 11lesions) ;

　4) villous elements form about 25 per cent (V＜T, 10lesions) ;

　5) tubular elements form the almost entire tumor with minimal villous elements (T(v), 4lesions) ;

　6) tubular elements form the whole tumor (T, 10lesions).

　As villous elements became more predominant, the tumor macroscopically appeared more villous and granular but less nodular on the surface. Radiographically reticular and/or granular patterns with feathery margin were more frequently seen in cases with dominant villous elements of tumor. In addition, a fine granular and villous patterns with much adherent mucus and relatively mild reddening with white spots were common endoscopically in those with dominant villous elements.

　In summary, the radiologic and endoscopic characteristics of villous tumor were seen when the tumor consisted of greater villous elements (V and V＞T). Therefore, we should define villous tumor as that with villous elements of more than 75 per cent of the entire tumor.