Aims: Prostate cancer (PCa) is highly heritable and one-half of associated pathogenic variants are in the BRCA genes. Genetic testing is recommended in localised PCa patients with elevated risk of mutations and in all patients with metastatic PCa (mPCa). The economics of genetic testing in mPCa has been evaluated previously, however, the value of testing patients with localised PCa has not been assessed. In this context we examined the cost-effectiveness of germline BRCA testing in localised PCa patients with high-risk of mutations with and without the inclusion of cascade testing of first-degree relatives (FDRs) of mutation carriers.
Methods: Cost-utility analysis of germline BRCA testing in localised PCa patients with 1) high/very high-risk PCa staging; 2) family history of PCa; 3) Ashkenazi-Jewish ancestry. Analyses were performed from an Australian payer perspective using semi-Markov multi-health-state transition models with a lifetime time horizon. Decision uncertainty was characterized using probabilistic 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 PCa staging, AU$3.9 million/QALY with a family history of PCa and AU$650,098/QALY in Ashkenazi-Jews. Extension of testing to FDRs resulted in ICERs of AU$18,872/QALY in high/very high-risk PCa, AU$47,294/QALY with a family history of PCa and AU$14,637/QALY in Ashkenazi-Jews. Probability of cost-effectiveness at a willingness-to-pay of AU$75,000/QALY was 0% in the patient-level analyses and 100% in most cascade testing scenarios.
Conclusion: Germline BRCA testing may not be cost-effective in localised PCa patients with a high-risk of mutations but demonstrates value for money when extended to blood related family members of variant-positive patients.