Australian women diagnosed with ovarian cancer before 2013, and their families, will be proactively identified and offered genetic testing for the BRCA1 and BRCA2 genes through a new international study, ‘TRACEBACK’.
Ovarian cancer takes more Australian women’s lives than any other gynaecological cancer. Like breast cancer, ovarian cancer is strongly associated with mutations in the BRCA1/2 genes. However, previous thinking underestimated the prevalence of BRCA1/2 mutations in ovarian cancer, meaning that many women diagnosed with ovarian cancer didn’t have access to genetic testing.
The framework for TRACEBACK, recently published in the Journal of Clinical Oncology, is part of an international program with strong leadership from Australia. It will be the first program in Australia to proactively and comprehensively identify women with a past history of ovarian cancer who missed out on genetic testing.
In Australia, the TRACEBACK initiative is being led by Professor David Bowtell and Associate Professor Paul James, Dr Rachel Delahunty and colleagues at the Peter MacCallum Cancer Centre in Melbourne and will recruit patients from right across Australia.
Professor Bowtell is an internationally renowned ovarian cancer genomicist, who heads the Ovarian Cancer Research Program at the Garvan Institute of Medical Research in Sydney and has a joint appointment at Peter Mac. Professor Bowtell’s work has already transformed the way we understand ovarian cancer. In 2013, his work changed the clinical genetic management of the disease in Australia, allowing women diagnosed with ovarian cancer to have genetic testing for the BRCA genes.
“Many women who were diagnosed with ovarian cancer before 2013 still don’t know whether they’re carrying a mutated BRCA1 or BRCA2 gene,” Professor Bowtell.
“Already, this has had a significant impact on cancer prevention. Many women who were diagnosed with ovarian cancer before 2013 still don’t know whether they’re carrying a mutated BRCA1 or BRCA2 gene. Retrospectively identifying and testing these women means that in the event they do carry the gene, their families can use risk-reducing strategies. Waiting for another cancer to develop in the family to become aware of the presence of one of these genes is unacceptable.
“Modeling based on the number of BRCA genes, or mutations that have been missed, the number of female relatives who may be carrying the mutation, and the type of cancers these mutations cause indicate that TRACEBACK has the potential to prevent around 800 ovarian cancers and more than 2000 breast cancers over a number of years. The sooner we can have TRACEBACK up and running, the better. Had they been diagnosed today, we’d be testing these women – and we want to ensure they aren’t missing out on information that could affect an entire family,” said Professor Bowtell.
TRACEBACK is just one part of Professor Bowtell’s broad approach to research aimed at improving outcomes for women diagnosed with ovarian cancer. Professor Bowtell’s entire research program works to understand the genetic basis, improved treatments and prevention of ovarian cancer. It is a multifaceted program with each project relying on patient recruitment, whole genome sequencing technology, clinical data collection and logistics coordination.
According to Professor David Thomas, Head of the Cancer Division at the Garvan Institute of Medical Research, “The impact of ovarian cancer is devastating. In 2017 alone, 1500 Australian women will be diagnosed with ovarian cancer, and more than 1000 women will pass away from this insidious disease. But we are making progress.
“All research within Garvan’s Cancer Division is aimed at providing better outcomes for patients, and Professor Bowtell’s work does just that. His research has already changed how ovarian cancer is treated, and this will continue. Through Garvan’s unparalleled capabilities in whole genome sequencing technology, Professor Bowtell’s research has the power to fast-track personalised and precision medicine for ovarian cancer.
“Garvan is proud to foster joint appointments, like Professor Bowtell’s with Peter Mac. It is through the power of collaborations like these that the benefits of cutting-edge and innovative research will be translated sooner to the clinic for the benefit of those with ovarian cancer,” said Professor Thomas.
One such project is seeking to understand how ovarian cancers evolve to make treatment ineffective. Many women with the most common type of ovarian cancer (called ‘high grade serous’, it is responsible for 70-80% of deaths) initially have a very good response to chemotherapy. Their cancer shrinks rapidly on treatment, but then the cancer evolves resistance to treatment, called acquired resistance. Professor Bowtell’s research has already identified several mechanisms involved in acquired resistance. This has important implications for drug selection in relapse in ovarian cancer as well as identifying who is at risk of chemoresistance.
Another major focus of Professor Bowtell’s work is to learn from the small number of patients – exceptional responders – who ‘beat the odds’ and survive much longer than five years (only 35–40% patients survive five years). Through an international collaboration, Garvan’s whole genome sequencing technology is applied in the hope that by understanding rare long-term survivors, new therapeutic approaches will be identified that will help women with more typical disease trajectories.
In addition, Professor Thomas’ Genomic Cancer Medicine Program, funded by NSW Health, uses genome sequencing to identify people at increased risk of cancer for more intensive screening. The program holds the real promise of being able to identify tumours months or years before physical symptoms appear and the cancers may have advanced too far to cure, a major problem in ovarian cancer.
Source: Garvan Institute