Primary malignant melanoma of the esophagus.

Primary malignant melanoma of the esophagus is exceedingly rare. We identified six patients seen at Memorial Hospital for Cancer and Allied Diseases over a period of 35 years. All patients were Caucasian, with an age range of 30 to 74 years (mean: 60 years). There were three men and three women. No association was noted with tobacco or ethanol use, nor was there a personal or family history of malignant melanoma. Symptoms were related to obstruction or hemorrhage. All tumors were polypoid and had attained large size at the time of initial diagnosis. Histologically, the melanomas had epithelioid, spindle-cell, and pleomorphic areas with focal melanin production. An intraepithelial "in situ" component was present in five cases and melanosis of the non-neoplastic esophagus in five. All six neoplasms were immunoreactive for S-100 protein, and none reacted with anticytokeratins. Two cases examined ultrastructurally showed premelanosomes. All patients were treated by esophagogastrectomy. The mean survival for four patients was only 2.1 months. The two remaining patients are alive at 5.5 and 11 months.