T stage and venous invasion are crucial prognostic factors for long-term survival of patients with remnant gastric cancer: a cohort study

BACKGROUND: The incidence of remnant gastric cancer (RGC) after distal gastrectomy is 1–5%. However, as the survival rate of patients with gastric cancer improves due to early detection and treatment, more patients may develop RGC. There is no consensus on the surgical and postoperative management of RGC, and the clinicopathological characteristics correlated with the long-term outcomes remain unclear. Therefore, we investigated the clinicopathological factors associated with the long-term outcomes of RGC. METHODS: We included 65 consecutive patients who underwent gastrectomy for RGC from January 2000 to December 2015 at the Osaka Medical and Pharmaceutical University Hospital, Japan. The Kaplan–Meier method was used to create survival curves, and differences in survival were compared between the groups (clinical factors, pathological factors, and surgical factors) using the log-rank test. Multivariate analyses using the Cox proportional hazard model were used to identify factors associated with long-term survival. RESULTS: No significant differences were noted in the survival rate based on clinical factors (age, body mass index, diabetes mellitus, hypertension, cardiovascular disease, pulmonary complications, liver disease, diet, history of alcohol drinking, and history of smoking) or the type of remnant gastrectomy. Significant differences were noted in the survival rate based on pathological factors and surgical characteristics (intraoperative blood loss, operation time, and the number of positive lymph nodes). Multivariate analysis revealed that the T stage (hazard ratio, 5.593; 95% confidence interval [CI], 1.183–26.452; p = 0.030) and venous invasion (hazard ratio, 3.351; 95% CI, 1.030–10.903; p = 0.045) were significant independent risk factors for long-term survival in patients who underwent radical resection for RGC. CONCLUSIONS: T stage and venous invasion are important prognostic factors of long-term survival after remnant gastrectomy for RGC and may be keys to managing and identifying therapeutic strategies for improving prognosis in RGC. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12957-021-02400-5.