NBIによる食道小扁平上皮癌の存在診断

Detection of Small Esophageal Squamous Cell Carcinoma by NBI

要旨　食道小扁平上皮癌32病変を遡及的に検討した結果，存在診断の感度は白色光66％，NBI84％，ヨード染色100％であった．ヨード染色は炎症を惹起するため表層が非腫瘍性上皮で再生され，内視鏡治療の妨げになることがある．一方，NBIは全く非侵襲的であり，食道小扁平上皮癌の存在診断に有用と思われた．しかし，32病変中1病変はNBIでは存在診断困難であったが，白色光では診断可能であったことから，食道小扁平上皮癌の存在診断には白色光とNBIの併用が重要と思われた．一方，ヨード染色の感度は100％であり，咽頭・食道癌治療後などのハイリスクグループに対するサーベイランスではいまだにヨード染色が必須と思われた．

　Usefulness of NBI for the early detection of superficial esophageal SCC has been reported. However, the detection sensitivity for small esophageal SCC by WL,NBI and iodine staining has never been reported.

　Patients and Methods : 32 lesions of small SCC（29 lesions of EP and 3 lesions of LPM, tumor median size : 3mm）treated by EMRC or ESD from May, 2005 to December, 2008 were enrolled in this study. The endoscopic pictures of WL, NBI and iodine were investigated retrospectively. The SCC was detected from the endoscopic findings such as protuberant, depression or color change by WL, well demarcated brown area by NBI and irregular unstained area by iodine, respectively. Small SCC was defined as a lesion 10mm or less in size.

　Results : Sensitivity of WL, NBI and iodine was 66％, 84％ and 100％, respectively.

　Conclusion : NBI was useful for the detection of small esophageal SCC, however the sensitivity of NBI was lower than that of iodine staining. Therefore, iodine staining is still necessary for the surveillance in the high risk group for esophageal SCC.