内視鏡的粘膜切除術を施行した表層拡大型食道癌の1例

Superficial Spreading Type of Esophageal Carcinoma Treated by Endoscopic Mucosal Resection, Report of a Case

要旨　患者は55歳の男性．人間ドックで食道病変を指摘され，当科に紹介され入院した．入院後の内視鏡検査では右壁中心の約半周性の発赤した浅い陥凹性病変を認め，ヨード染色で不染帯の長径は約6cmに及んでいた．食道X線検査ではEi右壁に壁陥凹像を認め，口側にかけて連続した壁硬化像を認めた．深達度m3と診断したが，患者の希望で内視鏡的粘膜切除術（EMR）が施行された．切除標本では大きさ5.2×2.4cmの0-Ⅱc＋Ⅱb，表層拡大型，組織診断は高分化型扁平上皮癌，ly₀，v₀，深達度m3であった．術後1年1か月，再発なく健在である．表層拡大型食道癌症例に対するEMRの適応の問題点としては，多分割切除による断端判定の困難性，および多中心発生の可能性が考えられ，局所再発，異時性多発に対する，より慎重な経過観察が必要であると思われた．

　A 55-year-old male was diagnosed as having an esophageal cancer by routine endoscopic examination, and was admitted to our hospital for further evaluation and treatment. Endoscopically, the lesion was seen as a slightly depressed reddish mucosal area of about 6 cm in length, which was unstained with iodine. Barium swallowing examination revealed abnormal shadows and mucosal irregularity on the right wall of the middle and lower thoracic esophagus. Although, the depth of invasion was diagnosed as m3 preoperatively, the patient underwent endoscopic mucosal resection (EMR) by his desire. Histopathological examination revealed type 0-Ⅱc+Ⅱb, superficially spreading type carcinoma, measuring 5.2×2.4 cm in size, well differentiated squamous cell carcinoma, partly invading the lamina muscularis mucosa (m3), no lymphatic permeation (ly₀), and no venous permeation (v₀) . He has been in good health without recurrence for one year and one month since the resection. A difficulty to diagnose the tumor margin histologically due to piecemeal resection and a possibility of multicentric carcinogenesis were considered to be the problem of EMR for superficial spreading type of esophageal carcinoma.