418P Analysis of the efficacy of cytokine-induced killer cell therapy in adjuvant treatment of colorectal cancer

Abstract

In the past decade, cell-based immunotherapy has been reported to improve clinical outcomes in cancer patients by altering tumour immune responses and improving prognosis and overall survival rates. This retrospective study aimed to evaluate the efficacy of cytokine-induced killer (CIK) cell infusion as an adjuvant therapy in patients with colorectal cancer. A total of 764 patients with colorectal cancer admitted to the Cancer Hospital of China Medical University, Liaoning Cancer Hospital & Institute from June 2006 to September 2017 were retrospectively analysed. All patients were treated with surgery for primary lesions, and then adjuvant chemotherapy was administered according to the NCCN guidelines. Among these patients, 394 patients received CIK therapy (CIK group), while the other 370 patients who had similar demographic and clinical characteristics did not receive CIK cell infusion therapy (non-CIK group). Patients were followed up and data were analysed by χ2 test, Kaplan-Meier and Cox regression. Our results showed that the 3- and 5-year OS rates were 88.71% and 83.68%, respectively, in the CIK group, and 79.24% and75.3%, respectively, in the non-CIK group. The OS in the CIK group was significantly higher than in the non-CIK group (P<0.01). At different stages according to AJCC 8 Cancer Staging Manual, the OS for patients with stage I CRC was not statistically significant between the two groups, P=0.195. The OS of patients with stage II∼IV CRC in the CIK group was significantly higher than in the non-CIK group, P values were 0.001, 0.033 and 0.008, respectively. Differentiation of primary tumour and CIK cell treatment were significantly associated with improved OS in the univariate analysis. Further multivariate survival analysis indicated that CIK cell treatment remained associated with improved OS. In addition, the OS in the chemotherapy plus CIK group was significantly higher than in the chemotherapy alone group (P < 0.001). The side effects in the chemotherapy plus CIK group were lower than in the chemotherapy alone group. The 5-year OS increased with the increase in cycles of treatment, which was statistically significant. CIK cell therapy can improve the efficacy of adjuvant chemotherapy in patients with colorectal cancer. Multicentre, large-sample randomized controlled trials are still needed to confirm these results.