INTRODUCTION: The aim of this prospective, observational, multicenter study was to examine the epidemiology and management costs of bone metastatic disease (BMD) in patients with lung cancer. METHODS: The analysis included all patients with BMD from lung cancer diagnosed between May 2006 and May 2007 in 40 centers. We analyzed their management and the direct costs of BMD from the health care provider's perspective, using a Markov model. Skeletal-related event (SRE) was defined as pathological fractures, spinal cord compression, or hypercalcemia (clinical SRE [cSRE]) for an initial analysis; a second analysis included palliative radiotherapy and surgery (therapeutic SRE [tSRE]). RESULTS: Among the 554 patients enrolled (62 ± 11 years, 76.5% males, 69.3% performance status 0/1, 91% non-small cell lung cancer), 24.7% had a cSRE and 26.7% a tSRE at baseline and 9% and 39% during follow-up, respectively; 81.8% received at least one chemotherapy cycle. The median survival time was 5.8 months, and the 1- and 2-year survival rates were 22% and 7%, respectively; there was no significant difference in overall survival between the patients with and without SRE at enrollment. The main BMD treatments were opiate therapy (77.7%), biphosphonates (52.3%), radiotherapy (42.1%), and surgery (9.2%). The mean monthly BMD treatment costs in euros were €190, €374, and €4672 for asymptomatic patients, symptomatic patients, and patients with SRE, respectively. The average first-year BMD management cost in euros was €3999 ± 4135 (95% confidence interval: 374-15,886), and 49.5% of this cost was attributable to patients with SRE. CONCLUSIONS: This analysis confirms the poor prognosis of BMD from lung cancer and underlines the burden of SRE in overall treatment costs.