まだら食道を背景とした食道癌の初期浸潤所見

Early Invasive Cancers of the Esophagus in Patients with Multiple Lugol-voiding Lesions

要旨　食道内にヨード不染部が多発するまだら食道には，食道癌が多発しやすいことが知られている．筆者らはまだら食道に対する定期的な食道癌のサーベイランス中に初めて癌と診断できるようになった粘膜固有層浸潤癌を初期浸潤癌として検討を行った．通常内視鏡観察で初期浸潤癌は0-IIb型もしくは極めてわずかに陥凹した0-IIc型を示し，上皮内癌と鑑別するのは困難であった．一方，NBIで観察すると初期浸潤癌には“延長したループ状血管”が7/12病変，“ループ状血管に囲まれた小さなAVA様所見”が5/12病変にみられ，上皮内癌に比べ高率であったため，初期浸潤癌に特徴的な所見と考えられた．

　The esophagus with multiple Lugol-voiding lesions is an important risk factor for multiple esophageal cancers. Early esophageal cancer, such as epithelial or lamina propria mucosal cancers, are frequently detected during surveillance of patients with multiple Lugol-voiding lesions. Lamina propria mucosal cancers detected during surveillance endoscopy for these patients were defined as “early invasive cancers” in this study. Differentiating “early invasive cancers” from epithelial cancers was challenging, using a non-magnified white light image. Elongation of loop vessels and a small avascular area surrounded by loop vessels were typical findings for “early invasive cancers”. “Early invasive cancers” may be differentiated from epithelial cancers based on these findings.