Cellular immunotherapy plus chemotherapy ameliorates survival in gastric cancer patients: a meta-analysis

The efficacy of cellular immunotherapy plus chemotherapy in treatment of gastric cancer (GC) remains inconsistent even controversial. Hence, we performed a meta-analysis to better comprehend the clinical value of cellular immunotherapy plus chemotherapy for GC patients. We searched PubMed, Embase and EBSCO databases to identify the studies evaluating the association of cellular immunotherapy plus chemotherapy and overall survival (OS) and/or disease-free survival (DFS) in patients with GC, and then combined relevant data into hazard ratios (HRs) for OS, DFS and clinicopathological features such as TNM stage, etc. with STATA 12.0. Eleven studies with 1244 patients were included in this meta-analysis. We found that cellular immunotherapy plus chemotherapy remarkably improved overall survival (OS) and diseases-free survival (DFS) as compared to the chemotherapy for GC patients. In subgroup analyses, pooled data showed that the combined therapy was significantly associated with better 3-year and 5-year survival rate, but not with 1-year survival rate of patients; the application of cellular immunotherapy based on either CIK or DC-CIK cells could enhance survival as well as NK, gamma delta T and CIK cells-based immunotherapy. More importantly, the addition of cellular immunotherapy considerably improved OS and DFS only in patients with stage III rather than stage II. In addition, we also discovered that the combined therapy did not cause intolerable side effects to patients. Cellular immunotherapy plus chemotherapy ameliorates survival in GC, especially in patients with stage III, implicating that it is a valuable therapeutic strategy for these patients.