About

In 2009 my mum was diagnosed with Ovarian cancer. Around 3-4 years after her diagnosis, and after extensive research, she found out she was positive for having a harmful variant of the BRCA gene. The BRCA gene, as I will explain in detail later on, is a gene which can make you more likely to develop various types of cancer. Today there are a number of ways to help reduce developing cancer if you have tested positive for the gene, yet by the time my mum was aware of these processes, her cancer had progressed too far.

 

Over the past 2 years I have been debating on whether or not I want to get tested for the BRCA gene (the legal age is 18), and it has shocked me how barely any of my friends know what the gene is, how you can be tested for it, and the preventative measures you can take. I cannot help but constantly wonder what would’ve happened if my mum would’ve got tested for the gene before her diagnosis; if she’d still be here now? And get angry at the thought that a 3-4 year gap could’ve changed so much. In the recent couple of weeks I have felt obligated to educate my friends on the BRCA gene and thought I’d write about a new blog post on everything I know about it.

 

What is the BRCA gene?

The name BRCA is an abbreviation for “Breast cancer gene”. BRCA1 and BRCA2 are two different genes which are known to impact a person’s chances of developing breast cancer or ovarian cancer. Everyone has two copies of these genes, one copy inherited from each parent, however they become known as “tumour suppressor genes” because when they have certain changes, variants or mutations, cancer can develop. People who have inherited a harmful variant in BRCA1 and BRCA2 also tend to develop cancer at younger ages than people who do not have such a variant. Each child of a parent who carries any mutation in either of these genes has a 50% chance of inheriting the mutation. (It is important to note however that not everyone who has the gene mutation will go on to develop breast or ovarian cancer.)

 

Breast cancer

A woman’s risk of developing breast of ovarian cancer is increased if inherited a harmful variant in BRCA1/2, yet the degree of increase will vary depending on either mutation.

Roughly 13% of women in the general population will develop breast cancer at one point during their lives. However 55%-72% of women who inherit a BRCA1 variant and 45%-69% of women who inherit a BRCA2 variant will develop breast cancer by 70-80 years old. Those with the gene variants also pose an increased risk of developing cancer in the opposite breast in the years following their original breast cancer diagnosis. The risk of this reaches 20-30% at a 10 year follow up, and 40-50% at a 20 year follow up.

 

Ovarian cancer

Around 1.2% of women in the general population will develop ovarian cancer sometimes during their lives. Yet 39%-41% of women with a BRCA1 variant and 11%-17% of women with a BRCA2 variant will develop ovarian cancer by age 70-80. The likelihood of carrying an inherited mutation in BRCA1/2 varies within population groups. While the prevalence within the general population is 0.2%-0.3% (1 in 400), the prevalence of people from Ashkenazi Jewish decent is higher, at 2%.

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Testing

While testing for the general public is available to see if you’ve inherited a mutant BRCA1/2 gene, it is recommended by healthcare professionals that these tests should be focused on those who have a higher likelihood of carrying a harmful variant – e.g. one with a long family history of breast/ovarian cancer.

 

Before testing is carried out, you’ll have a risk assessment with a healthcare counsellor to review key factors, such as the family history of BRCA gene variants. If this assessment suggests that you have an increased risk of carrying the gene, the counsellor will discuss the benefits and harms of testing them. It is also suggested to have genetic counselling before hand, to help understand what either test results (positive or negative) will mean. It’s recommended that children under 18 do not undergo genetic testing for BRCA1/2 variants. This is due to the fact that there are no risk-reduction strategies for children. The majority of the time, women cannot take action until after they’ve had children.

 

Reducing the risk of developing cancer after a positive test result

Various options are available for reducing cancer risks in people who have inherited a harmful BRCA1/2. Including enhanced screening, surgery and chemoprevention.

 

Enhanced screening

Women who test positive for harmful BRCA genes may start breast screening at younger ages than the general population, having more frequent breast screenings via MRI or mammograms. Whilst men also carry harmful variants in BRCA1 and 2, the benefits of screening men for breast and other cancers aren’t known however it is encouraged to have regular breast exams at age 35 and regular screening for prostate cancer age 40.

 

Risk reducing surgery

This surgery consists of removing as much harmful or “at risk” tissue as possible. This includes having one or both breasts removed to reduce the risk of developing breast cancer, or removing a woman’s ovaries and fallopian tubes to reduce the risk of her developing ovarian cancer. However these surgeries do not guarantee that you won’t develop cancer later on in life, as to why they’re called risk reducing rather than preventative.

 

Chemoprevention

This involves the use of medications to reduce the risk of developing cancer. Two chemopreventive drugs have been known to reduce the risk of breast cancer in women at increased risk, yet its role in women with harmful BRCA1 or 2 variants is not clear enough yet. This is usually the option for women who choose not to/ can’t undergo risk reducing surgery. It has also been found that women who carry harmful BRCA variants, along with women in the general population have roughly a 50% lower risk of ovarian cancer if they’ve taken oral contraceptives (the contraceptive pill). However it is also noted that potential harms of oral contraceptives (that include oestrogen) include increased risk of breast cancer and cervical cancer.

 

As I am starting to go through the process of being tested myself, I’ve had years of debate about the benefits and harms of finding out at such a young age whether I have inherited mutant BRCA1 or 2 genes. One thing that sticks out for me is that if I am to test positive, there are not many preventative measures I can take until after I’ve had children (e.g. having a full hysterectomy). I’ll also have to accept that, if positive, the safest option to have children is via IVF (testing/screening the eggs to see if they carry the gene) – a long, expensive and draining process. Yet the potential that my test results are negative include a huge sense of relief. While a negative result does not ensure that I will live my life cancer free, it will put me at less of a risk. As I mentioned before, whenever I think about BRCA testing and how it has improved so much in recent years, I cannot help but sit and think that if my mum had her test done before her diagnosis, she may still be here with me today. I now feel obligated to educate as many people as I can about BRCA testing and how important it is to get tested.