Prognostic value of resected lymph nodes numbers for Siewert II gastroesophageal junction cancer

We aim to evaluate whether resected lymph nodes (RLNs) numbers have prognostic value in patients with gastroesophageal junction cancers (GEJ, Siewert type II). Patients with gastroesophageal junction cancers were identified from the Surveillance Epidemiology and End Results (SEER) registry between 1988 to 2013. Multivariate Cox regression analyses and Kaplan-Meier method were performed to analyze risk factors for overall survival (OS) and cause-specific survival(CSS). A total of 8396 patients who underwent surgeries and had reginal lymph nodes examined were identified. Kaplan-Meier analysis indicated that more numbers of resected lymph nodes (RLNs) were associated with better survival. The five-year OS rates for 1-20 and 21-90 RLNs were 26.8% and 32.4%, with a median survival time of 62 and 72 months, respectively (P < 0.001). The five-year CSS rates were 32.2% and 37.2% in each group, with median survival time of 90 and 101 months, respectively (P < 0.001). Cox regression multivariate analysis showed that year of diagnosis, age, sex, marital status, grade, seer histology, tumor histology, lymph node ratio (LNR) and RLNs as a categorical variable were all significant prognostic factors for both OS and CSS. RLN count is an independent prognostic factor for Siewert type II GEJ cancer patients and patients can achieve better overall and cancer-specific survival with more than 20 RLNs dissected.