Concurrent chemoradiotherapy plus cytokine-induced killer cells therapy or observation in patients with locoregionally advanced nasopharyngeal carcinoma: A ten-year follow-up of a randomized, phase II study.

2558 Background: Concurrent chemoradiotherapy (CCRT) is the standard of care for patients with locoregionally advanced nasopharyngeal carcinoma (NPC). We aimed to evaluate the efficacy and safety of Cytokine-Induced Killer cells (CIK) consolidation therapy in combination with CCRT in these patients. Methods: Patients with locoregionally advanced NPC were randomized in a 1:1 ratio to receive concurrent chemoradiotherapy therapy plus CIK consolidation therapy or concurrent chemoradiotherapy alone in this single-center, randomized, phase II study. The primary endpoints were disease-free survival (i.e., survival period free from disease recurrence [distant metastasis and/or locoregional recurrence] or death from any cause) and overall survival in the intention-to-treat population. Safety was a secondary endpoint. Results: 58 patients were enrolled in this study (29 in the CIK therapy group and 29 in the control group). The median follow-up time was 144.70 months. In the CIK therapy group, the 10-year disease-free survival rate was significantly higher than that in the control group (82.5% versus 61.3%; hazard ratio for recurrence or death, 0.258; 95% confidence interval [CI], 0.094-0.712; P=0.005). The 10-year overall survival rate was 86.2% and 67.5%, respectively; (hazard ratio for death, 0.377; 95% CI, 0.131-1.087; P=0.06). The main adverse effects of CIK was fever which resolved after symptomatic treatment. In the CIK therapy group, 23.1% of patients experienced acute adverse events of grade 3 or 4 versus 17.2% in the control group during CCRT. The most frequent adverse events of grade 3 are mucositis, followed by decreased appetite, marrow suppression. Conclusions: CIK consolidation therapy plus CCRT significantly improved disease-free survival in patients with locoregionally advanced NPC. (This trial is registered with Chinese CilnicalTrial.gov, number ChiCTR-TRC-08000262). Clinical trial information: ChiCTR-TRC-08000262 .