Is SABR cost-effective in oligometastatic cancer? An economic analysis of the SABR-COMET randomized trial

X. Melody Qu, Yujie Chen, Gregory S. Zaric, Suresh Senan, Robert A. Olson, Stephen Harrow, Ava John-Baptiste, Stewart Gaede, Liam A. Mulroy, Devin Schellenberg, Sashendra Senthi, Anand Swaminath, Neil Kopek, Mitchell Liu, Andrew Warner, George B. Rodrigues, David A. Palma, Alexander V. Louie*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Purpose: The phase 2 randomized study SABR-COMET demonstrated that in patients with controlled primary tumors and 1 to 5 oligometastatic lesions, SABR was associated with improved progression-free survival (PFS) compared with standard of care (SoC), but with higher costs and treatment-related toxicities. The aim of this study was to assess the cost-effectiveness of SABR versus SoC in this setting. Methods and Materials: A Markov model was constructed to perform a cost-utility analysis from the Canadian health care system perspective. Utility values and transition probabilities were derived from individual-level data from the SABR-COMET trial. One-way, 2-way, and probabilistic sensitivity analyses were performed. Costs were expressed in 2018 CAD. A separate analysis based on US payer's perspective was performed. An incremental cost-effectiveness ratio (ICER) at a willingness-to-pay threshold of $100,000 per quality-adjusted life year (QALY) was used. Results: In the base case scenario, SABR was cost-effective at an ICER of $37,157 per QALY gained. This finding was most sensitive to the number of metastatic lesions treated with SABR (ICER: $28,066 per QALY for 2, increasing to $64,429 per QALY for 5), difference in chemotherapy use (ICER: $27,173-$53,738 per QALY), and PFS hazard ratio (HR) between strategies (ICER: $31,548-$53,273 per QALY). Probabilistic sensitivity analysis revealed that SABR was cost-effective in 97% of all iterations. Two-way sensitivity analysis demonstrated a nonlinear relationship between the number of lesions and the PFS HR. To maintain cost-effectiveness for each additional metastasis, the HR must decrease by approximately 0.047. The US cost analysis yielded similar results, with an ICER of $54,564 (2018 USD per QALY) for SABR. Conclusions: SABR is cost-effective for patients with 1 to 5 oligometastatic lesions compared with SoC.
Original languageEnglish
Pages (from-to)1176-1184
Number of pages9
JournalInternational journal of radiation oncology, biology, physics
Volume109
Issue number5
Early online date2021
DOIs
Publication statusPublished - 1 Apr 2021

Cite this