The cost-utility of targeted germline BRCA testing in localised prostate cancer followed by cascade testing first-degree relatives with pathogenic variants.

Purpose: Genetic testing is recommended in localised prostate cancer (PCa) with elevated risk and in metastatic PCa (mPCa). The economics of genetic testing in mPCa has been evaluated but not assessed in localised PCa. We examined the cost-utility of germline BRCA testing in localised PCa with high-risk of pathogenic variants.

Methods: Cost-utility analysis of germline BRCA testing in localised PCa with 1) high/very high-risk classification; 2) family history of PCa; 3) Ashkenazi-Jewish ancestry. Analyses were performed from an Australian payer perspective using semi-Markov models over lifetime; quality-adjusted life years (QALYs) were the health outcomes. Decision uncertainty was characterized using one-way and probabilistic sensitivity analyses.

Results: The incremental cost-effectiveness ratio (ICER) of BRCA testing compared to no testing was AU$591,408/QALY in high/very high-risk patients, AU$3.9 million/QALY with family history of PCa and AU$650,098/QALY in Ashkenazi-Jews. Adding cascade testing of first-degree relatives (FDRs) resulted in ICERs of AU$18,872/QALY, AU$47,294/QALY and AU$14,637/QALY in the aforementioned groups. At a willingness-to-pay of AU$75,000/QALY, BRCA testing was not likely to be cost-effective in PCa patients; however, was cost-effective after cascade testing FDRs.

Conclusion: Germline BRCA testing may not be cost-effective when limited to patients with localised PCa but demonstrates value for money when extended to FDRs.