3）拡大内視鏡

The Detection of Superficial Esophageal Carcinoma by NBI Magnified Endoscopy

要旨　食道表在癌の診断においてヨード染色は簡便であるが，炎症の惹起により病変の形が変わり，刺激が強く侵襲的である．また生検を施行すると病変の形が変わり，線維化を起こすため内視鏡治療の妨げになることがある．一方，近年開発されたNBIは簡便で非侵襲的で，SCCの大部分はBA（brownish area）として認識される．しかし，炎症もBAを呈するため，NBIの感度は高いが，特異度は低い．本稿ではNBI拡大内視鏡による血管パターン解析がBAの鑑別診断に有用か否かをretrospectiveに検討した．その結果，腫瘍性BAでは異常血管が認められると同時に血管間背景粘膜が変化することが判明した．今後はNBI拡大観察によるBAの鑑別診断を多施設共同前向き試験として実施する必要がある．

　Iodine staining is a useful method for the early detection of superficial esophageal SCC（squamous cell carcinoma）. However, iodine causes severe inflammation, and sometimes the area of SCC becomes unclear. Biopsy is also a useful method for the diagnosis of SCC. However, sometimes the biopsy disturbs endoscopic treatment. Because the shape of lesion is changed, and fibrosis is caused by biopsy.

　On the other hand,NBI（narrow band imaging） is a very simple, non invasive and useful detection device. The sensitivity of NBI is high. However, the specificity and PPV are low. The authors tried to use magnified endoscopy to increase the PPV. SCC showed an irregular, dilated vascular pattern. On the other hand, the non-SCC BA（brownish area）showed a regular vascular pattern by NBI magnified endoscopy. In addition,NBI magnified endoscopy could detect non-BA SCC by the irregularity of vessels. Therefore,NBI magnified endoscopy was useful for the differential diagnosis of BA.