大腸pSM癌に対する内視鏡治療根治基準の拡大―リンパ節転移予測因子に関する検討─特殊染色による脈管侵襲判定を中心に

Risk Factors for Lymph Node Metastasis of Submucosal Invasive Colon Cancer: Emphasis on Detection of Vessel Permeation Using Special Stains

要旨　内視鏡摘除後追加治療の適応基準にかかわる大腸SM癌のリンパ節転移危険因子につき検討した．多変量解析で有意差がみられた因子は脈管（リンパ管and/or静脈）侵襲のみであった．脈管侵襲は転移危険因子の中で最も重要とされ，その判定に関し当院では特殊染色の効果を報告している．HE染色施行脈管侵襲評価によるリンパ節転移診断能は，感度75.0％，特異度50.3％であったが，特殊染色の場合，感度93.8％，特異度46.0％，陽性的中率12.9％，陰性的中率98.9％となった．特殊染色によって感度が向上し，脈管侵襲陰性ならばリンパ節転移がほぼ確実にないと判断できる点で意義があると考えられた．

　Risk factors for lymph node metastasis of submucosal invasive colon cancer are related to the indication of additional surgery after endoscopic resection. In this investigation of ours, multivariate logistic analysis showed vessel（lymphatic and/or venous）permeation to be the independent and significant risk factor.

　Vessel permeation has been reported to be the most important risk factor. We have reported on the effectiveness of its detection using special stains. With respect to ability to diagnose the likelihood of lymph node metastasis, the calculated sensitivity, specificity,PPV（positive predictive value）, and NPV（negative predictive value）of detection of vessel permeation using special staining were 93.8％,46.0％,12.9％, and 98.9％, respectively. HE（hematoxylin and eosin）staining had 75.0％sensitivity and 50.3％specificity. This result indicates that investigating vessel permeation using special stains is extremely useful for more accurate identification of patients who need additional surgery after endoscopic resection.