Faster genetic test, improved access to ovarian cancer drug

A new genetic testing service at Mater has slashed four months off the time it takes for Queensland ovarian cancer patients to access potentially life-saving drugs.

Patients previously had to wait up to five months to find out if their cancer was linked to variants in their BRCA1 and BRCA2 genes, but now they can access results in just four weeks.

Patients with a variant can be prescribed PARP inhibitor medication — which blocks recurrence of the cancer and can dramatically improve survival rates.

The reduction in waiting time is due to the commissioning of Mater Pathology’s own advanced 3500 Series Genetic Analyser which was funded by Mater Foundation.

An estimated 1300 Australian women were diagnosed with ovarian cancer in 2022. Ovarian cancer is the deadliest gynaecological cancer, with a five-year survival rate of 49%.

Mater’s Director of Anatomical Pathology, Rohan Lourie, said the enhanced testing and DNA sequencing operation was a major boost for ovarian cancer treatment in Queensland.

“Around 20% of ovarian cancer patients will have a genetic variant in one of their two BRCA genes, either in their inherited DNA or isolated in the tumour DNA itself,” Lourie said.

“This is critical information because it identifies the likely cause of their cancer and if other family members may be at risk.

“Reducing the turnaround time for testing means that those patients with BRCA variants can access new and effective inhibitor medications more quickly and that other treatments can be identified for patients without these variations.”

Mater previously relied on interstate and overseas laboratories, but in October it commenced routine onsite testing for up to 16 different genes. Variations within these genes have been linked to a range of cancers, including ovarian, breast, endometrial and prostate cancers.

South Brisbane campus treats around 130 new public and private ovarian cancer patients a year, all of whom undergo genetic screening.

Since August 2020, all patients with BRCA variants have been able to access the PBS-funded PARP inhibitor Olaparib. A typical course of the drug costs $140,000.

Dr Nimithri Cabraal, a gynaecological oncologist at Mater Hospital Brisbane, said new drugs such as Olaparib were saving and extending women’s lives.

“Without a doubt, PARP inhibitors are one of the biggest advances in treatment of ovarian cancer,” Cabraal said.

“There has been a massive increase in survival rates of women with BRCA genetic variants.

“One study showed that using PARP inhibitor medication at the end of chemotherapy reduced the risk of reoccurrence or death by 70% over four years in patients on PARP inhibitor medication.

“This sort of improvement is almost unheard of in studies, so it is a game changer for these women.”

She said Olaparib works by blocking PARP proteins from repairing DNA in ovarian cancer tumours.

“When our DNA is damaged it has the ability to repair itself through a number of mechanisms, but on Olaparib the repairs are inhibited, causing cancer cells that carry a BRCA mutation to die,” Cabraal said.

“It really is a life-changing treatment for women who have these mutations.

“Every woman diagnosed with the types of ovarian cancer that might be caused by BRCA variants should have genetic analysis — and the fact we can do that so quickly at Mater is a massive win for those women.”

Margaret Gooch, 65, of Magnetic Island, was diagnosed with ovarian cancer just under a year ago and had to wait five months for tests to confirm a BRCA variant in her tumour.

The tumour had already been removed at Mater and she was prescribed a two-year course of Olaparib. She recently returned to work part-time as a QUT social science researcher, working mostly from home.

“Learning I had the variant in the tumour was good news because it meant I could have Olaparib treatment, but at the same time it wasn’t an inherited variant.

“I still get tired, but my chemo markers are all in the normal range and my blood tests are showing very good results.

“I’ve been able to go back to work, which I love, and I’m back doing yoga, singing in my choir and living on a beautiful island with a fantastic community.”

Image caption: Dr Rohan Lourie with the Genetic Analyser. Image: Supplied