食道m3・sm1癌の質的・量的EUS診断

Endoscopic Ultrasonography for Patients with Esophageal Carcinoma Invading the Muscularis Mucosae or Upper Submucosa

要旨　食道表在癌に対する深達度診断には高周波数細径超音波プローブが有用であり，9層構造を基本としてm3浸潤の有無が診断可能である．問題点は，微小浸潤を診断することが困難であること，微細な層構造の描出率が高くはないことであると思われる．現在においてもm3・sm1領域における正診率は十分とは言えず，m3・sm1と診断された場合でもできる限りEMRを試みることが推奨される．組織学的にm3・sm1と診断され，追加治療の必要性を検討する際にEUSによるリンパ節の情報が重要な意味を持ってくる．また，仮に転移陰性と診断され，追加手術が行われなかった場合，経過観察にEUSは重要な役割を担う．

　The imaging procedures using a high frequency miniature probe are considered to be useful for the diagnosis of the depth of invasion in superficial esophageal carcinoma. The problems for diagnosis were that to visualize micro invasion was very difficult and normal nine-layered structure could not be visualized in some cases. Because the diagnostic accuracy of a miniature probe is hardly sufficient, endoscopic mucosal resection to obtain a histological diagnosis is recommended for patients with esophageal carcinoma diagnosed as m3 or sm1. To decide what additional treatment should be used for patients with esophageal carcinoma histologicaly confirmed to be m3 or sm1, the diagnosis for lymph node metastasis by using endoscopic ultrasonography is useful. If such patients fail to undergo surgical resection, endoscopic ultrasonography as a follow-up procedure is considered to be necessary.