Surgery Combined with Radiotherapy Improved Survival in Metastatic Esophageal Cancer in a Surveillance Epidemiology and End Results Population-based Study

This retrospective study used a population-based national registry to determine the impact of local treatment modalities on survival in patients with metastatic esophageal cancer (EC). The Surveillance Epidemiology and End Results (SEER) database was used to identify patients with metastatic EC from 1988 to 2012. A total of 9,125 patients were identified. There were 426 patients underwent primary surgery, 4,786 patients were administered radiotherapy (RT) alone, 847 patients underwent surgery plus RT and 3,066 patients without any local treatment. Multivariate analysis results indicated that year of diagnosis, age, race, histologic subtype, grade and local treatment modalities were independent prognostic factors for overall survival (OS). The 5-year OS were 8.4%, 4.5%, 17.5% and 3.4% in primary surgery, RT only, surgery plus RT and no local treatment, respectively (P < 0.001). Subgroup analyses showed that the impact of RT was mainly reflected by preoperative radiotherapy, as patients received preoperative radiotherapy had significantly better OS than patients who underwent primary surgery alone and postoperative RT, the 5-year OS rates were 24.7%, 6.5% and 7.8%, respectively, respectively (P < 0.001). Surgery plus RT, especially preoperative RT, may improve long-term survival of patients with metastatic EC.