Acute-phase reaction induced by zoledronate and its effect on prognosis of patients with advanced non-small cell lung cancer

•prospective study of 23 patients with advanced non-small cell lung cancer.•zoledronate was administered and patients monitored for acute-phase reaction (APR).•APR was related to higher γδ T cell numbers and increased cytokines.•improved overall survival was observed in patients with APR. Zoledronate (ZOL) is usually used for prevention of skeletal-related events in cancer patients with bone metastases. The first administration of ZOL is occasionally associated with development of acute-phase reaction (APR), which is due to activation of γδ T cells. ZOL-related APR was associated with better overall survival (OS) of patients with non-small cell lung cancer (NSCLC) in our previous retrospective study. However, it remains to be clarified whether γδ T cells are more activated in patients who experienced ZOL-related APR, and whether γδ T cell activation is involved in prolongation of OS. Twenty-three patients with advanced NSCLC were recruited between 2012 and 2014 in this study. We administered ZOL to participants with standard care. The patient characteristics, change in γδ T cell counts and cytokines, OS, and skeletal-related event-free survival were compared between patients with APR (APR group) and those without APR (non-APR group). Ten patients (43.5%) experienced a ZOL-related APR. The number of γδ T cells at baseline in the APR group was significantly higher than that in the non-APR group. Serum interleukin-6 and tumor necrosis factor-α in the APR group were significantly increased, but no change in the number of γδ T cells was observed after the first administration of ZOL in both groups. OS in the APR group was significantly longer than that in the non-APR group (median survival time: 23.1 vs. 14.5 months, p