Clinical significance of zoledronic acid and strontium-89 in patients with asymptomatic bone metastases from non-small-cell lung cancer.

BACKGROUND: The purpose of this study was to clarify the treatment value of zoledronic acid (ZA) and/or strontium-89 (Sr-89) in patients with non-small-cell lung cancer (NSCLC) with asymptomatic bone metastases (BMs).

PATIENTS AND METHODS: Eligible patients were those with resectable NSCLC and asymptomatic BMs. These candidates were randomized into 4 groups: group A was treated with ZA and Sr-89 simultaneously, group B was treated with ZA, group C was treated with Sr-89, and group D was untreated. Patients were monitored and analyzed for the first skeletal-related event (SRE), overall survival (OS), and annual incidence of SREs.

RESULTS: One hundred eighty patients were enrolled. Time to first SRE in group A was 15 months (95% confidence interval [CI], 14.0-16.0 months), in group B it was 12 months (95% CI, 11.1-13.0 months), in group C it was 9 months (95% CI, 8.5-9.5 months), and in group D it was 8 months (95% CI, 7.1-8.9 months) (P = .000). The overall survival (OS) in group A was 17 months (95% CI, 16.0-18.1 months); in group B, it was 16 months (95% CI, 14.2-17.8 months); in group C, it was 12 months (95% CI, 11.1-12.9 months); and in group D, it was 12 months (95% CI, 10.8-13.2 months). The annual incidence of SREs in group A was 24.4%; in group B, it was 55.6%; in group C, it was 75.6%; in group D, it was 91.1% (P = .000).

CONCLUSIONS: Treatment with ZA and/or Sr-89 significantly extended the time to first SRE as well as survival time and reduced the annual incidence of SREs. Treatment with the combined use of ZA and Sr-89 was safe and well tolerated and achieved the best effect on asymptomatic BMs of NSCLC.