Background: Patients with bone metastases secondary to prostate cancer are predisposed to skeletal-related events (SREs), including spinal cord compression, pathological fracture, surgery to bone and radiotherapy to bone. The objective of this study was to document current patterns of healthcare utilization and costs of SREs in patients with prostate cancer and bone metastases.
Methods: This was a retrospective, observational study using the Thomson MedStat MarketScan Commercial Claims and Encounters database from September 2002 to June 2011. Study subjects included all persons with claims for prostate cancer and for bone metastases, and one or more claims for an SRE. Unique SRE episodes were identified based on a gap of at least 90 days without an SRE claim, and classified by treatment setting (inpatient or outpatient) and SRE type (spinal cord compression, pathological fracture, surgery to bone or radiotherapy).
Results: Of 3919 patients with prostate cancer and bone metastases, 2090 (53%) had one or more SRE episodes. Among 1237 patients who met all other criteria, there were 1623 SRE episodes over a mean (s.d.) follow-up of 16.1 (12.9) months. The percent of episodes that required inpatient treatment ranged from 14% (radiotherapy) to 82% (surgery to bone). On average, inpatient episodes with surgery to bone (n = 36 episodes) were most costly (mean (s.e.) $88,838 ($11,830)/episode), whereas outpatient episodes with surgery to bone (n = 8 episodes) were least costly (mean (s.e.) $4749 ($1690)/episode). Of the total SRE costs (mean (s.e.) $20,984 ($951)/episode), 41% were attributable to outpatient radiotherapy (n = 1169 episodes), 23% to inpatient radiotherapy (n = 184 episodes), and 19% to inpatient treatment of pathological fractures (n = 101 episodes).
Conclusions: In patients with prostate cancer and bone metastases, SREs are associated with high costs and hospitalizations.