原発性食道悪性黒色腫の1例

Malignant Melanoma of the Esophagus, Report of a Case

要旨　患者は57歳，男性．嚥下時不快感を主訴に近医を受診．上部消化管内視鏡検査にて下部食道に隆起性病変を指摘された．胸部下部食道左壁に径3cm大の広基性の隆起性病変を認めた．その表面は凹凸を有するが，平滑であり，正常上皮によって覆われていた．隆起は部分的に軽度発赤を認めたが，色素沈着は認めなかった．生検の結果，炎症性の変化と診断された．全生検目的にEMRを施行した．病理学的検討の結果，悪性黒色腫と診断された．患者の希望により放射線照射による治療が選択され，60Gyの放射線照射を行った．EMR後12か月経過し，現在無再発生存中である．

　Malignant melanoma of the esophagus is rare with only 146 cases having been reported in the past 40 years in Japan. Its prognosis is extremely poor. We report a case of malignant melanoma of the esophagus.

　A 57-year-old male visited another hospital complaining of dysphagia. Endoscopic examination revealed a protruded tumor in the lower esophagus. No pigmentation of the esophageal mucosa was noted. He was referred to our hospital for further examination and treatment. Endoscopic biopsy of the tumor was diagnosed as an inflammatory reactive change of mesenchymal cells. Endoscopic mucosal resection (EMR) was performed for total biopsy of the tumor. Pathological studies of the resected specimen revealed primary malignant melanoma of the esophagus. The patient received radiation therapy (60 Gy) after the mucosal resection and is alive 12 months after EMR therapy without any sign of recurrence. From this, we conclude that malignant melamoma should be included among the differential diagnoses of submucosal esophageal tumor.