Clinical pathological features of 180 cases with primary esophageal malignant melanoma

Objective: To investigate the clinical pathological and epidemiological characteristics of primary esophageal malignant melanoma (PMME). Methods: The clinical pathology data of 180 PMME patients in the esophageal cancer database of the key laboratory of esophageal cancer research in Henan Province from 1973 to 2016 were collected, of which 136 were male, aged (58.5±9.0) years, 44 were female, aged (56.7±12.2) years. Kaplan-Meier and Log rank test were used for survival analysis, Cox regression scale model was used for risk factor analysis. Results: The incidence of PMME is 0.036% (180/500, 000), mostly were male (about 3∶1 for men: female). The common sites of PMME were the lower part of the esophagus (48.9%, 85/174), followed by the middle section of the esophagus (46.0%, 80/174) and the upper part of the esophagus (5.2%, 9/174). No black particles were seen in the PMME cells of 3 patients under microscope, and strong positive expressions of Melan-A and HMB453 were observed in these 3 patients by immunohistochemical results. Of the 129 patients who had a routine preoperative esophageal biopsy, 69 were undiagnosed with PMME (53.5%). The medium survival time of the whole group was 7.9 months, and the survival rates of 1, 2, 3, 5 years were 25.0%, 7.9%, 6.6% and 1.3%, respectively. The univariate analysis showed that N, M, TNM phase and radiotherapy were related to the overall survival of patients (P<0.05). Multivariate analysis showed that TNM phase and radiotherapy were the independent risk factors for overall survival of patients (P<0.05). Conclusions: PMME is more common in men, the common site of the disease is the lower part of the esophagus. The preoperatively missed diagnosis rate of Chinese PMME is high. TNM phase and radiotherapy are the independent risk factors for overall survival of patients.