食道表在癌に合併した咽頭および食道melanosisの1例

Pharyngeal and Esophageal Melanosis Accompanied by Superficial Esophageal Carcinoma, Report of a Case

要旨　61歳，男性．上部消化管内視鏡スクリーニング検査にて食道表在癌，食道静脈瘤，咽頭・食道melanosisを認めたため，当院紹介となった．食道静脈瘤に対しEVL，食道癌に対しEMRを施行し，咽頭・食道melanosisは現在経過観察中である．食道melanosisの組織学的所見では粘膜上皮内にメラニン色素を有するmelanocyteの増殖を認めた．他症例の電子顕微鏡検査では，メラニン色素を有するmelanosomeを含むmelanocyteの増殖を認めた．食道melanosisは高飲酒歴，高喫煙歴の症例に多くみられ，食道癌と同様のリスクファクターを有することから，食道melanosisを有する症例は食道癌の発生に注意が必要である．

　A 61-year-old male, diagnosed with esophageal superficial carcinoma, esophageal varices and melanosis of the pharynx and esophagus by upper digestive endoscopy was referred to our hospital. Esophageal carcinoma was treated by endoscopic mucosal resection (EMR) using the EEMR-tube method, and esophageal varices were treated by endscopic variceal ligation (EVL). Melanosis of the pharynx and esophagus are being followed up by endoscopy. Histological examination revealed pigmented melanocytes amongst the keratinocytes in the epithelium. Melanosis has been frequently observed in the upper aerodigestive tract of Japanese heavy-smoking alcoholic men, so this indicates that the presence of esophageal melanosis can lead to a high risk for neoplasms of the esophagus.