1618 – Testing of tumour prostate tissue to detect BRCA1/2 pathogenic gene variants in men with metastatic castration-resistant prostate cancer to help determine eligibility for PBS olaparib

New MBS item.

The proposed medical service is testing of prostate tumour tissue to detect BRCA1/2 (BReast CAncer gene) gene variants in men with metastatic castration-resistant prostate cancer to determine eligibility for treatment with olaparib.

Type: Investigative

When localised, prostate cancer can be cured with surgery or radiotherapy, but some patients will relapse with either overt metastases or an isolated rise in prostate-specific antigen. There is also a proportion of men who have metastases when the prostate cancer is first diagnosed. Prostate cancer is termed ‘castrate resistant’ when the disease progresses despite continuous androgen deprivation therapy. After this, further treatment is needed to maintain disease control.

This application concerns the metastatic disease, which is a small part of the overall disease and is furthermore targeted at those patients with genetic mutations in their homologous recombination repair (HRR) genes. A small percentage of prostate tumours have loss of function mutations in candidate genes involved in HRR of DNA. BRCA1, BRCA2, or ATM are the most well characterised and/or frequently mutated HRR genes in prostate cancer. The overall mutation frequency for these three genes together range from 13% to 26.5% in metastatic castration resistant prostate cancer.

• PASC meeting: 17 April 2020
• ESC meeting: 11 to 12 February 2021
• MSAC meeting: 
  • 31 March to 1 April 2021
  • 25 to 26 November 2021