Autologous transplantation of cytokine-induced killer cells as an adjuvant therapy for hepatocellular carcinoma in Asia: an update meta-analysis and systematic review

BACKGROUND: High recurrence rate after curative treatment is the major problem for hepatocellular carcinoma (HCC). Cytokine-induced killer cells (CIKs) therapy was extensively studied among HCC patients. However, the value of CIKs therapy was controversial. A meta-analysis was performed to investigate the efficacy of adjuvant CIKs after invasive treatments among HCC patients. METHODS: We searched online for literatures studying sequential CIKs therapy for HCC patients. Recurrence-free survival (RFS), progress-free survival (PFS) and overall survival (OS) were set as the main endpoints. Both overall and subgroup analysis were accomplished. RESULTS: A total of 12 clinical trials with 1,387 patients were included. The pooled analysis showed a significant improvement of RFS, PFS and OS in CIK group (HR 0.56, 95% CI 0.47-0.67, p<0.00001 for RFS; HR 0.53, 95% CI 0.40-0.69, p<0.00001 for PFS; HR 0.59, 95% CI 0.46-0.77, p<0.0001 for OS). The proportion of CD4(+) T cells increased significantly, while CD8(+) T cells decreased significantly after CIKs therapy (WMD 4.07, 95% CI 2.58-5.56, p<0.00001; WMD -2.84, 95% CI -4.67 to -1.01, p=0.002, respectively). No significant differences of adverse events between CIK and non-CIK group existed. CONCLUSIONS: Conventionally invasive therapies combined with CIKs therapy could improve the prognosis of HCC patients, especially for RFS and PFS, with mild side effects. Optimizing patient selection shall be the direction in future studies.