Could routine screening of BRCA gene mutation prevent hundreds of pancreatic cancer cases?

Researchers at Barts Cancer Institute, London, have recommended that all women over 30 should be tested for BRCA gene mutations.  Published in the Journal of the National Cancer Institute last week, the study estimates that if this recommendation is implemented, tens of thousands of lives will be saved.   

Ali Stunt’s blogs about the news, the connection with pancreatic cancer and what to do if you feel you may have the BRCA gene…

The researchers claim that routine screening for the BRCA mutation will pick up those women who either do not have or are not aware of a family history of those cancers and could save tens of thousands of lives.

BRCA, often referred to as the breast cancer gene, mutations can occur in around two per cent of breast cancer cases and three per cent of ovarian cancers.

But did you know that around five per cent of all pancreatic cancer patients also carry the BRCA1 and BRCA2 mutations?[1] In the UK that would equate to around 600 patients every year. (Click on what to do if you feel you have the BRCA gene)

No matter what your thoughts are on the validity and indeed costs of such screening, it is certainly an area for more in-depth evaluation.

What is interesting is a Canadian study published in 2015[2] found that of those who were BRCA1/2 positive they were no more likely than patients without the mutation to have had a previous diagnosis of either breast or ovarian cancer and, half of them did not have a strong family history of breast or ovarian cancer.

So, testing patients merely on the basis of family history could mean a lot of people who are BRCA1/2 positive could be missed – the point being made by the Barts Cancer Institute in their recommendation for widespread screening of women over the age of 30.

What is the BRCA gene?

BRCA1 and BRCA2 help stop cells becoming cancerous by producing proteins that fix damage to our DNA. All of the cells in our body undergo a daily cycle of DNA damage and repair. Faulty BRCA genes can reduce our ability to repair DNA damage. This means that DNA, not properly repaired, can cause cells to become cancerous.

BRCA1/2 mutations are publically known about for women with breast and ovarian cancers, but both men and women can inherit a ‘faulty’ BRCA1 or 2 gene from either their mother or father.

It is important that medical professionals such as GPs and oncologists along with the public are aware of the association between risk of pancreatic cancer and being BRCA1/2 positive. BRCA2 mutation carriers have a 3.5-fold risk of developing pancreatic cancer[3] Women with BRCA 1/2 mutation have been shown to have a 2.4-fold increase in incidence of pancreatic cancer[4]

What is also interesting, is that research is suggesting the possibility that those pancreatic cancer patients with the BRCA1/2 mutations who are treated with PARP inhibitors (Poly-ADPribose polymerases which are a family of nuclear enzymes that regulate the repair of DNA) and/or platinum chemotherapy drugs may improve survival. These treatments are still only available within clinical trials but, should they be successful, could offer further treatment options for this sub-group of pancreatic cancer patients.

What we need now is for pancreatic cancer patients to be routinely tested for BRCA1/2 in order to determine whether they will benefit from targeted therapies such as PARP inhibitors. Plus, we need to raise awareness that there is a clear association between the BRCA1/2 mutations and pancreatic cancer.

What to do if you feel you may have a genetic mutation?

If you have cancer that runs in your family and you are concerned you too could develop cancer, then it is a good idea to speak to your GP. They may refer you for a genetic test which will tell you whether or not you have one of the inherited cancer risk genes.

Usually, if you have had a relative who has had cancer then they will need to have had the genetic test before any healthy relatives like you. If their genetic test is positive, then you can have the  test. It could take a few weeks for the test results to come back.

EUROPAC (European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer) are also available to identify gene changes that may increase risk in these families.

For more information on EUROPAC which is based in Liverpool, UK – click here

If the test is positive it doesn’t mean you have or will have cancer.

A positive test means you have a faulty gene that raises your risk of developing cancer, as medical history, lifestyle and your environment along with your genes will also influence any future health risks.

If you have one of the faulty BRCA genes, there is a 50% chance you will pass this on to any children you have and a 50% chance that each of your siblings also has it.

The genetics clinic will discuss with you how a positive or negative result will affect your life and your relationships with your family.

There is more information available from the Royal Marsden in their Beginners Guide to BRCA1 and BRCA2 which is well worth a read.

It is also worth noting that, in the majority of hereditary pancreatic cancer cases, the genes that might cause pancreatic cancer are currently not well known

Visit www.alistunt.org to see all of Ali’s blogs.

[1] Holter S, Borgida A, Dodd A, et al. Germline BRCA mutations in a large clinic-based cohort of patients with pancreatic adenocarcinoma.  J Clin Oncol. Epub 2015 May 4.

[2] Holter S, Borgida A, Dodd A, et al. Germline BRCA mutations in a large clinic-based cohort of patients with pancreatic adenocarcinoma.  J Clin Oncol. Epub 2015 May 4.

[3] The Breast Cancer Linkage Consortium. Cancer Risks in BRCA2 Mutation Carriers. J Natl Cancer Inst. 1999; 91(15):1310-6.

[4] Iqbal J, Ragone A, Lubinski J, Lynch HT, Moller P, Ghadirian P, Foulkes WD, et al. The incidence of pancreatic cancer in BRCA1 and BRCA2 mutation carriers. Br J Cancer. 2012; 107(12):2005-9.