Table 1.

Clinical studies applying CIK cells for the treatment of gastric cancer.

Study	Number of patients	Therapy	Results	Conclusions
Jiang et al., 2006 [21]	57	Gastrectomy and chemotherapy; immunotherapy group: additional CIK infusions	Better survival rate of patients in immunotherapy group only in beginning—after 2 yrs no difference in survival between the groups	Combination of chemo- and CIK cell therapy superior to chemotherapy alone in patients with advanced gastric cancer
Shi et al., 2012 [22]	151	Gastrectomy and chemotherapy; immunotherapy group: additional CIK cell therapy	The mean CD3+, CD4+ level and the CD4+/CD8+ ratio increased in patients' blood up to 2 months after immunotherapy; no severe side effects; OS and DFS significantly better in immunotherapy group	CIK cell therapy can prolong DFS and OS; patients with intestinal-type tumors benefit most from CIK cell therapy as determined by retrospective subgroup analysis
Wang et al., 2013 [23]	42	Chemotherapy; immunotherapy group: additional i.p. perfusion of CIK cells	Reduced volume of 2-cycle peritoneal fluid drainage in immunotherapy group; no serious adverse reactions; prolonged TTP and higher OS in immunotherapy group	Superior efficacy of combination of chemo- and CIK cell therapy for advanced gastric cancer patients with ascites; CIK cell therapy can enhance immunological function and prolong survival
Jiang et al., 2008 [24]	60	Chemotherapy; immunotherapy group: additional CIK cell transfusions	The remission rate was 58.6% in the immunotherapy group and 45.2% in the control group; side effects of CIK cell transfusions were chills, fever, general malaise, nausea, and vomiting	CIK cell therapy can reduce clinical signs of elderly advanced gastric cancer patients; side effects can be treated with conventional therapy
Jiang et al., 2010 [25]	156	Chemotherapy; immunotherapy group: additional CIK cell therapy	Significantly longer 2- and 5-yr survival time	Better survival after CIK cell therapy; increasing the frequency of CIK cell therapy seems to be beneficial for survival
Zhao et al., 2013 [26]	165	Gastrectomy and chemotherapy; immunotherapy group: additional CIK cell therapy	Improved 5-yr PFS and OS in immunotherapy group; within the immunotherapy group, the frequency of CIK cell therapy, clinical stage, and follow-up therapy were the most important factors for PFS and OS	CIK cell therapy can prevent recurrence and improve survival in combination with gastrectomy and chemotherapy

CIK: cytokine-induced killer; OS: overall survival; DFS: disease-free survival; i.p.: intraperitoneal; TTP: time to progression; PFS: progression-free survival.