大腸過形成性ポリープの自然史および過形成性ポリポーシスの形態

Natural History of Hyperplastic Polyp of the Colon and Morphologic Features of Hyperplastic Polyposis

要旨　組織学的に過形成性ポリープと診断された46病変について，X線学的に経時的および遡及的検討を行った．その結果，平均4.1年の期間で過形成性ポリープの98％は大きさの変化は認められなかった．また，形態的な変化も認められなかった．経過観察例からみた結果を踏まえて，過形成性ポリープの形態およびその自然史の特徴について報告した．また，1cm以上の扁平な過形成性ポリープを混在した2例の過形成性ポリポーシスの症例を報告し，通常の過形成性ポリープとの比較を行った．

　Radiologic pictures of 46 lesions of the regular type of hyperplastic polyp (HP) of the colon which were confirmed by histopathologic examination were evaluated retrospectively.

　(1) The HPs smaller than 5 mm in size were usually smooth and oval in shape, although some of the HPs larger than 5 mm and smaller than 10 mm in size might be rough and oval in shape.

　(2) About 98% of the HP did not change In size during the observation period of 4.1 years on the average and no HP changed in shape.

　(3) The HP larger than 1 cm in size may be extremely rare.

　 The results on the hyperplastic polyposis were summarized as follows:

　(1) The shape of each polyp was the same as that of HP, but the HPs larger than 10 mm in size might be found in the hyperplastic polyposis.

　(2) Six-year follow up observation of a case with hyperplastic polyposis showed that the polyps did not changes in shape and size.

　(3) Hyperplastic polyposis may be attributed to familial factor, and there was high incidence of gastrointestinal cancer in the family.