類基底細胞癌の粘膜下浸潤を伴った0-Ⅱc型表層拡大型食道表在癌の1例

Type 0-Ⅱc Superficial Spreading Esophageal Carcinoma Accompanied by Submucosal Invasion of Basaloid Carcinoma, Report of a Case

要旨　患者は60歳，男性．胃潰瘍の経過観察の目的で行われた近医の内視鏡検査で食道の異常を指摘されたため来院した．食道造影所見では，Imの全周性に及ぶO-Ⅱc型表層拡大型表在癌の所見で，辺縁の壁硬化・伸展不良を認めた．内視鏡所見では，陥凹内の凹凸不整とトルイジンブルー斑状濃染部を認め，推定深達度m₃と診断した．術後病理所見では，深達度m₁の中分化扁平上皮癌の中に，狭い範囲で粘膜下層深部への類基底細胞癌成分の浸潤が見られた．

　A 60-year-old man was referred to our hospital for a thorugh examination of the middle esophagus, where, at another clinic, an abnormal condition had been noticed during a follow-up endoscopy for gastric ulcer. Double-contrast radiography of the esophagus showed faint and irregular-shaped barium flecks in the middle esophagus, extending 60 mm in length annularly. On a lateral radiograph, poor-distensibility was recognized on the right wall of the lesion. Endoscopically, a reddish and slightly depressed lesion with an irregular granular mucosa was observed annularly. In it, discolored mucosal thickness and deformity of the esophageal cavity were demonstrated locally. We therefore diagnosed superficial spreading carcinoma invading the muscularis mucosae (m₃). Histological diagnosis revealed a moderately differentiated squamous cell carcinoma with a component of basaloid carcinoma invading the deep submucosal layer(sm₃). Because of the unusual form of invasion, we could not estimate the depth of invasion accurately.