Results of Surgical Treatment for Primary Malignant Melanoma of the Esophagus: A Multicenter Retrospective Study (2019 International Thoracic Oncology Summit #P5)

OBJECTIVE: Few large-sample research data sets exist on long-term survival and prognostic factors among patients with primary malignant melanoma of the esophagus (PMME), a rare malignancy associated with poor outcomes. We sought to investigate postoperative survival and prognostic factors in patients with PMME. METHODS: We retrospectively analyzed long-term follow-up results for patients with PMME who underwent surgery at 10 Chinese centers between January 1998 and January 2018. We performed uni- and multivariate analyses to investigate clinicopathologic factors associated with survival. RESULTS: Median overall survival for the entire group (N = 70 patients) was 13.5 months. Female sex (hazard ratio [HR], 0.352; 95% confidence interval [CI], 0.138-0.900; P = .029), ≥12 lymph nodes dissected (HR, 0.274; 95% CI, 0.133-0.563; P < .001), absence of lymph node metastasis (HR, 0.195; 95% CI, 0.084-0.451; P < .001), and postoperative adjuvant therapy (HR, 0.474; 95% CI, 0.249-0.901; P = .023) were factors of favorable prognosis. Preoperative pathologic diagnosis of PMME was as low as 47.1%. A high proportion of patients had lymph node metastasis, including those with early-stage tumors. Rates of lymph node metastasis were 54.2% (13/24) for pT1, 44.4% (12/27) for pT2, 57.1% (8/14) for pT3, and 100% (5/5) for pT4. Regional lymph node recurrence (N = 43 [61.4%]) was the predominant postoperative pattern of recurrence or metastasis. CONCLUSIONS: Female sex, pN0, increased number of lymph nodes dissected, and postoperative adjuvant therapy were associated with better outcomes among patients with PMME. Preoperative pathologic diagnosis of PMME was low, patients had lymph node metastasis (even those with early-stage tumors), and regional lymph node recurrence was common.