Breast cancer

Updated 08 November 2017

Do you have the breast cancer gene?

Nearly 95% of women don’t have the breast cancer gene, but are still at risk of developing breast cancer.

Angelina Jolie’s admission a few months ago that she had both breasts removed in a double mastectomy, after testing positive for the breast cancer gene, has put a spotlight on breast cancer prevalence.

Yet according to a local doctor, while the story has boosted breast cancer awareness, it fails to point out that only 5% of women carry this gene – leaving 95% of women who don’t carry it, but could still develop breast cancer.

Dr Owen Nosworthy, a Specialist Physician/Medical Oncologist at Wits Donald Gordon Medical Centre says that Angelina’s case is “rare and exceptional” as the gene responsible, BRCA1, is actually very rare and he cautions against women rushing out to get tested.

“The genetic test for BRCA1 is not freely available and requires that your doctor refers you to a specialist who will then take your blood to get tested. The average woman is unlikely to test positive for it, however, and I wouldn’t recommend that many women do this unless they have a family history of breast cancer.

“The implications of the test are quite profound and women who undergo it need counselling before they do so. The reason for this is that if you do test positive for the gene, it has a major impact on your future,” he says.

Breast cancer in SA

While there are no figures on how many women have breast cancer in South Africa, Dr Nosworthy says the numbers are ‘significant’ and breast cancer is one of the most common cancers in South Africa.

According to the Cansa Foundation, one in 29 women in South Africa will be diagnosed with breast cancer and one in 344 with ovarian cancer.

Nosworthy said double mastectomies were also uncommon and preventative mastectomies were just as rare an occurrence. One of the reasons for this is that medical schemes do not cover preventative mastectomies.

Another reason is that the BRCA1 gene, which is also responsible for ovarian cancer, is actually only found in roughly 5% of women. However, women who do not carry the gene are also at risk, especially if they fall into one of the following risk categories:

  • If you have a strong family history of breast cancer, especially a mother or a sister who had breast cancer.
  • If someone in your family has tested positive for the gene.
  • Older women who have been on hormone replacement medication are at risk.
  • Women who are pregnant for the first time over the age of 35.
  • Women who have never had children.

What to do if you’re at risk?

So what happens if you find yourself in Angelina’s position? You have a family member who had breast cancer (in this case it was her mother) and you have tested positive for the BRCA1 gene. But you’re still young and want to start a family -  should you wait to have a mastectomy?

“Young women who are aware of their risk and are carefully monitored should still be able to go through a pregnancy provided they don’t leave it too late. But the longer the breasts and ovaries remain in the body, the greater the risk,” explains Dr Nosworthy.

 In Angelina’s case she chose to undergo the preventative double mastectomy, reducing her risk from almost 90% down to 5%. But there is still a chance she could develop breast cancer. And ovarian cancer, which is why at some point she will also have to have her ovaries removed by means of a hysterectomy.

 “Angelina will still have to go for regular check-ups, and until she has her ovaries removed she is still at significant risk for ovarian cancer too. This is why we say that if you get tested for the gene, you need to be counselled. The implications of the test are profound, whether you test positive or not,” he says.

Yet even if you test negative, or if you have no family history, Dr Nosworthy says the best you can do is regular self examinations.

He says your first mammogram need not be until you are 35 or 40, the reason for this being that younger breasts are very dense and this makes them difficult to read on a mammogram.

“It’s worth noting that most lumps are not cancer, but you need to make your doctor aware of them regardless. Self-monitoring and examination is your best defence,” he says.

For a graphic on how to do a breast self-examination click here


Read Health24’s Comments Policy

Comment on this story
Comments have been closed for this article.

Ask the Expert

Breast cancer expert

Dr Gudgeon qualified in Birmingham, England, in 1968. She has more than 40 years experience in oncology, and in 1994 she founded her practice, Cape Breast Care, where she treats benign and malignant breast cancers. Dr Boeddinghaus obtained her qualification at UCT Medical School in 1994 and her MRCP in London in 1998. She has worked extensively in the field of oncology and has a special interest in the hormonal management of breast cancer. She now works with Dr Gudgeon at Cape Breast Care. Read more.

Still have a question?

Get free advice from our panel of experts

The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical exmanication, diagnosis and formal advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.

* You must accept our condition

Forum Rules