Adjuvant cytokine-induced killer cell immunotherapy improves long-term survival in patients with stage I–II non-small cell lung cancer after curative surgery

Non-small cell lung cancer (NSCLC) remains the most common cancer worldwide, with an annual incidence of around 1.3 million. Surgery represents the standard treatment in early-stage NSCLC when feasible. However, because of cancer recurrence, only approximately 53% of patients with stage I and II NSCLC survive 5 years after radical surgery. The authors performed a retrospective study to investigate the impact of cytokine-induced killer (CIK) cell immunotherapy on the long-term survival of patients with stage I-II NSCLC after curative resection.Fifty-seven patients with NSCLC were included in the study, with 41 and 16 in the control and CIK groups, respectively. Clinical characteristics were compared using a t-test and χ2 test. Survival analysis of patients with NSCLC was performed using the Kaplan-Meier method. The phenotypes and anti-tumor functions of CIK cells were evaluated by flow cytometry.Patients in the CIK group exhibited significantly longer overall survival (OS) and better disease-free survival (DFS) than those in the control group. Subgroup analysis indicated that patients with a higher risk of recurrence benefited more from CIK treatment and attained longer OS and DFS compared with those in the control group. No severe adverse events related to CIK treatment occurred. CIK cells contained a higher proportion of CD3+CD56+ natural killer (NK) T cells and CD3+ and CD8+ T cells and a lower proportion of CD3-CD56+ NK cells compared with peripheral blood mononuclear cells. CIK cells exhibited potent tumor-killing ability, with longer contact times with tumor cells and a greater number of cells exposed to tumor cells.The authors' data suggest that adjuvant CIK cell therapy is a safe and effective therapeutic strategy for improving OS and DFS in patients with stage I-II NSCLC after curative resection.