Gastrectomy for stage IV gastric cancer: a comparison of different treatment strategies from the SEER database

Abstract

In the West, more than one third of newly diagnosed subjects show metastatic disease in gastric cancer (mGC) with few care options available. Gastrectomy has recently become a subject of debate, with some evidence showing advantages in survival beyond the sole purpose of treatment tumor-related complications. We investigated the survival benefit of different strategies in mGC patients, focusing on the role and timing of gastrectomy. Data were extracted from the SEER database. Groups were determined according to whether patients received gastrectomy, chemotherapy, supportive care. Patients receiving a multimodality treatment were further divided according to timing of surgery, whether performed before (primary gastrectomy, PG) or after chemotherapy (secondary gastrectomy, SG). 16,596 patients were included. Median OS was significantly higher (p < 0.001) in the SG (15 months) than in the PG (13 months), gastrectomy alone (6 months), and chemotherapy (7 months) groups. In the multivariate analysis, SG showed better OS (HR = 0.22, 95%CI = 0.18-0.26, p < 0.001) than PG (HR = 0.25, 95%CI = 0.23-0.28, p < 0.001), gastrectomy (HR = 0.40, 95%CI = 0.36-0.44, p < 0.001), and chemotherapy (HR = 0.42, 95%CI = 0.4-0.44, p < 0.001). The survival benefits persisted even after the PSM analysis. This study shows survival advantages of gastrectomy as multimodality strategy after chemotherapy. In selected patients, SG can be proposed to improve the management of stage IV disease.

Figure 1

A, B Kaplan-Meier curve of overall survival (A) and cancer-specific survival (B). C, D Kaplan-Meier curves comparing OS (A) and CSS (B) between patients underwent or not gastrectomy (log-rank p < 0.0001). E, F Kaplan-Meier curves of OS (A) and CSS (B) among the different treatment groups (log-rank p < 0.0001). G Kaplan-Meier curves of OS comparing different pre-operative chemotherapy results in patients underwent secondary gastrectomy (log-rank p = 0.007). H Kaplan-Meier curves of OS comparing the effect caused by a complicated disease among patients underwent primary gastrectomy (log-rank p = 0.009)

Figure 2

A, B Kaplan-Meier curves of OS (A, log-rank p = 0.027) and CSS (B, log-rank p = 0.036) comparing primary and secondary gastrectomy after PSM. C, D Kaplan-Meier curves of OS (A, log-rank p = 0.019) and CSS (B, log-rank p < 0.021) comparing secondary gastrectomy and chemotherapy after PSM