Cost analysis of secondary prophylaxis with oral clodronate versus pamidronate in metastatic breast cancer patients

Abstract

Objective: We compared the direct medical costs of secondary prophylaxis with bisphosphonates (BPs) in bone metastases (BMs) of breast cancer (BCa) from a payer perspective.

Patients and methods: This study adopted an incidence-based chart review of consecutive BCa patients with BMs who received prophylactic treatment with orally administered (po) clodronate (CLODpo group), or intravenously administered (iv) pamidronate (PAM group) in 1997 at two large oncology centers in Toronto, Ontario. We evaluated the difference in costs of management of patients among the CLODpo and PAM groups using an intent-to-treat analysis from diagnosis of BMs to death, or last follow-up. The results are presented as observed mean and average lifetime (including terminal care) costs per patient.

Results: The observed mean costs in the PAM and CLODpo groups were 49,472 dollars and 50,307 dollars (2002 Canadian dollars), respectively. The difference in costs between the CLODpo (n=34) and PAM (n=18) groups was not significant (P=0.64), and remained robust after sensitivity analyses. The corresponding average lifetime costs were 65,677 dollars in the CLODpo group and 61,254 dollars in the PAM group. Inpatient and terminal care were the major cost drivers, comprising 45% and 25% of overall costs. Of all hospitalizations, 46% were associated with complications from BMs.

Conclusions: Our analysis, which was based on a convenience sample, failed to reveal a statistically significant difference in the observed mean costs between groups of patients who initiated treatment with po clodronate versus iv pamidronate. The cost estimates from this study can be used for future corroborative economic analyses.