Josie Dietrich should have been enjoying the thrills of new motherhood.
Instead, at 35 and just four years after her mother’s death from breast cancer at 56, she was thrust into the fight of her life.
When her son Felix was just eight months old, Ms Dietrich was diagnosed with breast cancer following a routine screening in 2009.
In the months and years afterwards, she underwent chemotherapy, had nine lymph nodes removed and a double mastectomy and reconstruction. Then her womb, ovaries and cervix were removed, leaving her unable to have any more children.
The new discovery by researchers from QIMR Berghofer of 72 previously unknown genetic markers for breast cancer may have given Ms Dietrich a clearer picture of her risk of breast cancer following the death of her mother.
“Everyone assumed mum’s diagnosis was just a once-off, that it was unusual. No one thought there was a genetic link that may one day have been passed on to me. If there was a test that I could have taken back then, I would have done it,’ she said.
‘If there was a test that I could have taken back then, I would have done it,’ she said.
QIMR Berghofer’s Professor Georgia Chenevix-Trench, one of the leaders of the international collaboration behind the discovery, said combined with existing knowledge, the research could one day help in the development of a predictive test for breast cancer.
She said a greater understanding of a woman’s risk of developing breast cancer may help to change the age at which a woman is offered mammogram screening and how often.
‘Many women are offered mammogram screening when they are middle-aged, but if we know a woman has genetic markers that place her at higher risk of breast cancer, we can recommend more intensive screening at a younger age,’ she said.
Professor Chenevix-Trench said the study found 65 genetic variants that predisposed women to overall risk of breast cancer, and a further seven variants that put a woman at higher risk of oestrogen-receptor negative breast cancer, which doesn’t respond to drugs like tamoxifen.
The discovery was made possible through collaboration between the Breast Cancer Association Consortium (BCAC) and the Consortium of Investigators of Modifiers of BRCA1/2, which is led by Professor Chenevix-Trench.
“We know that breast cancer is caused by complex interactions between these genetic variants and our environment, but these newly discovered markers bring the number of known variants associated with breast cancer to around 180,” she said.
Professor Chenevix-Trench, senior researcher Dr Jonathan Beesley, Functional Cancer Genomics specialists Associate Professor Stacey Edwards and Associate Professor Juliet French, collaborated with researchers from more than 300 institutions across the world to make the discovery.
Ms Dietrich, now aged 43, is determined to turn her battle against breast cancer into a positive. A memoir chronicling her journey, In Danger, is due to be published by UQP in April, 2018.
You can help QIMR Berghofer’s passionate team of researches solve the puzzle of breast cancer for future generations by making a gift today at qimrberghofer.edu.au/breastcancer.
100% of donations go directly towards research.
What is the BCAC?
The Breast Cancer Association Consortium (BCAC) is an international collaboration that was established to provide large sample sizes for examining genetic associations. In the past, sample collections were limited to what might be available from local hospitals.
To achieve the statistical power required to uncover true discoveries, the model for investigating diseases like cancer, diabetes and inflammatory bowel disease is to ‘join forces’ with other groups around the world.
Now the BCAC has a collection of 230 000 blood samples from women who’ve had breast cancer, and from unaffected women. Technology that was introduced just over 10 years ago has made it possible to easily compare the DNA from these blood samples from the two groups of women.
Using this large breast cancer collection, we have started to find many of these differences that show a skew towards the breast cancer group. We have found 72 previously unknown genetic markers for breast cancer using this comparison.