Treatment Outcomes of Surgery and <scp>ICI</scp> Therapy in 52 Patients With Esophageal Melanoma: A Retrospective Single‐Center Cohort Study

Primary malignant melanoma of the esophagus (PMME) accounts for only 0.5% of all melanomas but is associated with the shortest interval to disease progression and the highest metastasis rate. The optimal treatment for PMME remains elusive. The present study aimed to assess the utility of screening as a means of predicting the prognosis of PMME and to determine the efficacy of surgery and immune checkpoint inhibitors (ICIs) against this disease. Fifty-two patients with PMME treated at the National Cancer Center Hospital in Japan between 2010 and 2023 were enrolled. Survival analysis was performed for (i) patients with PMME (n = 52); (ii) resectable cases at the initial presentation (n = 36); and (iii) cases with systemic therapy (n = 37). The 5-year overall survival (OS) rate was 45.0%, and the median OS was 55.8 months. The 5-year OS rate of the patients in whom PMME was detected by screening and those in whom it was diagnosed clinically was 54.7% and 40.1%, respectively (p = 0.255). The presence of a lymph node metastasis was associated with a significantly higher recurrence and poorer prognosis. The 3-year RFS rate of the patients at the local and nodal stage was 57.8% and 6.9%, respectively (p < 0.0001). At surgery, the rate of lymph node metastasis in the recurrence group and the nonrecurrence group was 68% and 10%, respectively (p = 0.0027). In the patients who received ICI therapy, the 3-year OS was 33.3%, the median OS was 15.0 months, and the overall response rate was 23.5%. Our findings suggested that ICI therapy may improve survival in patients with advanced PMME. However, further research is warranted to identify both the clinical and molecular predictors of the treatment response as a means of improving patient selection.