Primary Malignant Melanoma of the Esophagus With Unusual Endoscopic Findings: A Case Report and Literature Review

Primary malignant melanoma of the esophagus (PMME) is a rare disease with an extremely poor prognosis. We experienced a 79-year-old man with PMME who had unusual endoscopic findings. On endoscopy, an elongated lump was detected on 1 side of the vertical axis of the esophagus. The mass extended progressively for 15 cm along the esophageal longitudinal axis and invaded half of the esophageal circumference. These endoscopic findings were not characteristic of PMME, and the condition was confirmed with biopsy and immunohistochemical staining. Here, we present this rare case and review the recent relevant literature regarding PMME. Doctors should be aware that PMME might present with unusual endoscopic findings.