大腸の鋸歯状腺腫（serrated adenoma）―私の診断基準

A Proposal of Histologic Criteria for Serrated Adenoma

要旨　大腸鋸歯状上皮性病変を暫定的にserrated adenoma，過形成性ポリープ，異型過形成性ポリープに分け，それらの組織学的特徴の分析を行い，serrated adenomaのより明確かつ客観的な組織診断基準（私案）の作成を試みた．serrated adenomaの組織学的特徴として，①腺管中層～表層の核偽重層，②好酸性細胞質，③腺管分岐像，の3所見が特異的であり，①を主所見，②，③を副所見として，それらを組み合わせた組織診断基準について述べた．

　We classified serrated epithelial lesions of the colon and rectum into serrated adenomas, hyperplastic polyp and atypical hyperplastic polyps, and analysed histologic features of these lesions to discover a more objective histologic criteria for diagnosing serrated adenoma.

　Through the analysis, the following findings showed high predictive value for diagnosing serrated adenoma: 1) Nuclear pseudostratification in the middle to the upper zone of the crypt, 2) Eosinophilic cell population and 3) Glandular budding or branching. We regarded 1) as a major and 2) and 3) as minor (accessary) indicators for serrated adenoma and proposed the combination of these three findings as histologic criteria to help diagnose serrated adenoma.