胃と腸46巻4号

2011年04月発行

今月の主題 大腸鋸歯状病変と癌化

主題

癌併存大腸広基性鋸歯状腺腫/ポリープの臨床病理学的特徴

著者： 三富弘之¹ 五十嵐誠治² 伴慎一³ 九嶋亮二⁴ 藤田恒平⁵ 平橋美奈子⁵ 大城由美⁶ 林大久生¹ 八尾隆史¹

所属機関： ¹順天堂大学医学部人体病理病態学講座 ²栃木県立がんセンター臨床検査部病理診断科 ³済生会川口総合病院病理診断科 ⁴国立がん研究センター中央病院病理科 ⁵九州大学大学院医学研究院形態機能病理学 ⁶松山赤十字病院病理部

ページ範囲：P.384 - P.393

文献概要

要旨　癌併存大腸広基性鋸歯状腺腫/ポリープ（sessile serrated adenoma/polyp ; SSA/P）37例49病変の以下のような臨床病理組織学的特徴を抽出できた．（1）高齢女性の右半結腸の広基性病変が多い，（2）粘膜下層浸潤（SM）癌が多い，（3）粘膜内（M）癌とSM癌では腫瘍全体の大きさに差はないが，癌部の大きさはSM癌が有意に大きい，（4）serrated type dysplasiaを伴う例が多い，（5）低異型度分化型腺癌が多い，（6）conventional type carcinomaを伴う例は，M癌ではSM癌に比し有意に少ない，（7）粘液癌併存例が比較的多い，（8）癌腺管構造の特徴をみるとM，SM癌ともに鋸歯状構造を示す例が多いが，M癌では小型の腺管形成が多く，SM癌では篩状構造が多くみられる，（9）小型の円形核を有する例が多い，（10）SM癌においても癌間質の炎症細胞浸潤は軽度で，線維化のない例が多い，（11）SSA/P部分の組織所見では腺底部の鋸歯状変化，分岐腺管，表層微小乳頭状増生巣，拡張腺管，水平腺管が多く観察された．以上より，癌併存SSA/Pはconventional typeの腺腫内癌とは異なる臨床病理学的特徴を有する特異な腫瘍と考えられる．

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