Role of zoledronic acid in nasopharyngeal carcinoma patients with bone-only metastasis at diagnosis. (October 2019) - Sun, Xue-Song
Highlights: NPC patients with bone-only metastasis receiving PCT usually exhibit SREs. The addition of ZA to PCT does not improve OS in these patients. However, ZA application effectively prevents SREs in this patient cohort. Abstract: Objective: We aimed to investigate whether zoledronic acid (ZA) can prevent skeletal-related events (SREs) and offer survival benefits for nasopharyngeal carcinoma (NPC) patients with bone-only metastasis at diagnosis. Materials and Methods: A total of 228 newly diagnosed NPC cases with bone-only metastasis were eligible for this retrospective study. Using the propensity score method (PSM) method, a well-balanced cohort was created for further analysis. Overall survival (OS) was the primary endpoint. The difference in survival was evaluated using the log-rank test. Hazard ratios (HRs) and 95% confidence intervals (CIs) for allcause mortality were derived from a Cox regression model. Cumulative incidence competing risk analyses using Fine and Gray's method was used to test the cumulative incidence of SREs between the different treatment groups. Result: In the PSM cohorts, patients in the platinum-based palliative chemotherapy (PCT) + ZA group and PCT alone group achieved similar 3-year OS (57.3% vs. 46.4%; log rank P = 0.188). Multivariate analysis indicated that ZA administration was not an independent prognostic factor (HR, 0.783; 95% CI, 0.267–2.300; P = 0.657). There was no significant difference in acute treatment toxicity between the 2 treatment groups, although the cumulative incidence of bone-related events (SREs) was significantly lower in the PCT + ZA group (Fine-Gray P = 0.026). Conclusion: ZA combined with PCT could not improve OS in NPC patients with bone-only metastasis at diagnosis. However, the incidence of SREs could be effectively prevented via ZA application.