Incidence and consequences of bone metastases in lung cancer patients

Background

Bone metastases (BM) are common in NSCLC patients. Despite some potential positive effects of bone-targeted therapies, their use in NSCLC is infrequent, which may relate to the overall poor prognosis of advanced lung cancer. We reviewed the literature to evaluate the incidence, consequences and use of bone-targeting agents in lung cancer patients with BM in both the trial and non-trial clinical setting.

Methods

Published prospective and retrospective papers investigating lung cancer and BM, in trial and non-trial settings, were identified and are discussed in this review.

Results

BM are common in patients with advanced lung cancer and often present symptomatically with pain and skeletal related events (SREs). Patients with high bone turnover marker levels, multiple BM, and history of pathological fractures have shorter overall survival. In randomized studies bone-targeted therapies reduced the risk of SREs and prolonged the time to first SRE. The use of bone-targeted agents may also be associated with a survival benefit.

Conclusion

BM are a common problem in advanced lung cancer. While the benefits of bone-targeted therapies have been demonstrated, their use is limited in non-trial populations. If better predictive markers of individual risk were available this might increase the appropriate use of bone-targeted agents.

Prevention and management of bone metastases in lung cancer: a review

Approximately 30 to 40% of patients with advanced lung cancer will develop bone metastases in the course of their disease, resulting in a significant negative impact on both morbidity and survival. Skeletal complications of bone metastases include pain, pathologic fractures, spinal cord compression, and hypercalcemia. Total medical care costs are greater among patients with bone metastases who develop skeletal complications. A randomized phase III trial of the third generation bisphosphonate zoledronic acid has shown clinical benefit in the management of a subgroup of patients with bone metastases from lung cancer. Zoledronic acid treatment was associated with a reduction in both the risk of, and time to, a skeletal-related event. One of the markers of bone resorption, N-telopeptide, is both prognositic for development of skeletal-related events and predictive for benefit from zoledronic acid. In preclinical models, bisphosphonates have also demonstrated antitumor activity and are therefore currently being evaluated in adjuvant trials. Inhibition of the receptor activator of nuclear factor kappa B ligand-RANK pathway can reduce osteoclast-mediated bone resorption, and trials comparing receptor activator of nuclear factor kappa B ligand inhibitors with bisphosphonates are ongoing, including patients with lung cancer. In this article, we review the management of bone metastases and hypercalcemia as well as potential future directions for bone directed therapies in patients with lung cancer.