Primary amelanotic melanoma of the esophagus.

Primary melanoma of the esophagus (PME) is an uncommon malignancy with less than 250 cases reported in the literature. Amelanotic PME is exceedingly rare and accounts for 10-25% of melanomas of the esophagus. A 59-year-old male with a history of mild dysphagia, heartburn, moderate anorexia and weight loss for 1 month is described. Barium swallow examination and videogastroscopy showed a polypoid, ulcerated mass located 30-38 cm from the incisors. No skin or eye melanoma lesions were found. Five biopsy samples were obtained. Histological examinations revealed proliferation of large, loosely cohesive cells of variable shapes and prominent central nucleoli in the deep mucosa. Immunohistochemical findings included positive vimentin, protein S-100, Melan A, and HMB-45, and negative AE1/AE3, CD 17, and desmin. A total transhiatal esophagectomy with high cervical esophagogastric anastomosis was performed. Peritumoral lymph nodes revealed malignant invasion. A diagnosis of primary amelanotic melanoma of the esophagus was made. Fourteen months after diagnosis the patient developed disseminated PME.