In May 2024 the S3 guideline "Prostate Cancer" (version 7.0) was updated. For the first time it is recommended to sequence genes involved in homologous recombination repair (HRR), e. g. ATM, BRCA1/2, BRIP1, CDK12, CHEK2, FANCA, HDAC2 and PALB2, before initiating a systemic therapy for castration-resistant prostate cancer (mCRPC).
The rationale behind the new recommendation is the still inconclusive study situation with regard to the predictive impact of HRR mutations on PARP inhibitor therapies in mCRPC. Based on the PROfound study, the PARP inhibitor Olaparib was approved in the EU at the end of 2020 as a monotherapy for patients with BRCA1/2-mutated mCRPC (Bono J et al. N Engl J Med 382:2091-2102, 2020). A clear benefit of Olaparib for mutation carriers of other HRR genes could not be derived from the study. Based on data from the PROpel study, Olaparib in combination with the hormone suppressor Abiraterone is approved for mCRPC patients with or without mutations in HRR genes (Saad F et al. Lancet Oncol 24:1094-1108, 2023). When deciding on a combination therapy of PARP inhibitor and abiraterone, the respective HRR mutation should be considered.
It is recommended to test the HRR genes on metastatic tissue if possible. In the case of bone metastases, attention should be paid to acid-free decalcification of the tissue with EDTA.
The AmoyDx® HANDLE HRR NGS Panel, a CE-IVD classified NGS assay, can be used to detect mutations in 27 HRR genes and in hotspot regions of BRAF, ERBB2, KRAS, NRAS and PIK3CA. Click here for more information about the panel.