The different prognostic factors between metastatic and nonmetastatic disease of esophageal neuroendocrine carcinoma

The specific risk factors of metastatic and nonmetastatic esophageal neuroendocrine carcinoma (NEC) are still uncertain. Whether primary site surgery is necessary for all patients with esophageal NEC is unknown. Patients with esophageal NEC in the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2014 were selected. STATA 12 was used to analyze the clinical and pathological features of esophageal NEC. In total, 241 patients with esophageal NEC were included. Metastatic patients had shorter overall survival than nonmetastatic patients (6.03 versus 11.90 months, respectively). Prognostic factors varied between metastatic and nonmetastatic esophageal NEC. The location of the primary tumor is a key point for the prognosis of esophageal NEC. For nonmetastatic esophageal NEC, patients with tumors in the upper third of the esophagus had the worst survival, and patients with metastatic esophageal NEC with a primary tumor in the lower part of the esophagus tended to have an increased risk of death. Moreover, age ≥68 years (hazard ratio [HR] = 2.05; 95% confidence interval [CI]: 1.28-3.31; P < 0.01) and large cell carcinoma (HR = 2.79; 95% CI: 1.30-6.00; P < 0.01) were independent risk factors in patients with metastatic esophageal NEC. Primary site resection benefited patients with nonmetastatic esophageal NEC (HR = 0.20; 95% CI: 0.07-0.56; P < 0.01) rather than patients with metastatic esophageal NEC (HR = 0.91; 95% CI: 0.29-2.83; P > 0.05). Our study presented that primary tumor location is an important risk factor for nonmetastatic esophageal NEC patients. Age and pathological type are important risk factors for patients with metastatic esophageal NEC. Nonmetastatic esophageal NEC will benefit from primary tumor resection. Systematic treatment is recommended for metastatic esophageal NEC.