[Primary malignant melanoma of the esophagus]. / Melanoma maligno primario de esófago.

Primary malignant melanoma of the esophagus is very rare, and only 139 cases have been described in all the world literature. We present one case of primary malignant melanoma of the esophagus in a 76-year-old woman who reported the symptoms of dysphagia and recent weight loss; the radiography showed a large polypoid mass filling the entire lower half of the esophagus, dark brown-black in the endoscopy. Histologic analysis demonstrated the existence of a malignant melanoma infiltrating the esophageal mucosa, composed of anaplastic cells with abundant brown pigment which had positive immunoreactivity for the S-100 protein.