食道胃接合部腺癌の深達度診断—超音波内視鏡の立場から

Depth Diagnosis of Esophagogastric Junction Cancer Using Endoscopic Ultrasonography

要旨●食道胃接合部腺癌におけるEUSによる深達度診断の有用性を検討するため，通常内視鏡検査にて粘膜下層浸潤が疑われ，深達度診断のためEUSを行った食道胃接合部腺癌（Siewert分類Type II）83例を対象に，SM2浸潤（>500μm）診断の精度を評価した．SM2浸潤の診断において，EUSの感度は85.0%で通常内視鏡に比べ高く，特異度は60.5%，正診率は72.3%であった．また，EUSの深達度診断において，0-IIc型，病理学的潰瘍ありは有意な深読みの因子であった．深達度診断が難しい食道胃接合部腺癌においてEUSは有用と考えられ，通常内視鏡，EUSを合わせた総合的な診断が望ましい．

　To evaluate the efficacy of EUS（endoscopic ultrasonography）for depth diagnosis of EGJ（esophagogastric junction）cancer, we investigated its ability to detect SM2（>500μm）invasion retrospectively. In total, 83 patients with EGJ cancer（Siewert Type 2）, who were suspected of having SM invasion through CE（conventional endoscopy）and underwent EUS, were included in this study. The sensitivity, specificity, and overall accuracy for SM2 or deeper using EUS were 85.0%, 60.5%, and 72.3%, respectively. The sensitivity of EUS was superior to that of CE. Type 0-IIc and pathological ulceration were independent risk factors for overestimation using EUS. Since accurate depth diagnosis for EGJ cancer can be difficult, both EUS and CE should be used for the diagnosis.