Breast and ovarian cancers
Breast cancer is the most common type of cancer in the UK with more than 50,000 women diagnosed each year, most of whom are aged over 50. One in eight women are diagnosed with breast cancer in their lifetime – but there is a good chance of recovery if it is picked up in its early stages.
Ovarian cancer is far less common. Around 1 in 100 women (1%) will be diagnosed with ovarian cancer by the age of 70. Though it is less common than breast cancer, ovarian cancer causes more deaths than any other cancer of the female reproductive system. Around 7,300 women are diagnosed with ovarian cancer in the UK each year. This makes ovarian cancer the 5th most common cancer in women, after breast, lung, bowel and womb cancer
About 5–10% of breast and 10-15% of ovarian cancers are hereditary. These hereditary breast and ovarian cancers are caused by inherited changes in genes such as BRCA1 and BRCA2.
Breast and ovarian cancer genes: BRCA1 and BRCA2
Recent publicity has improved our understanding of the clinical importance of testing the breast and ovarian cancer genes, BRCA1 and BRCA2. Both genes are important in identifying the risk of developing breast and ovarian cancer. A lady who carries a faulty BRCA1 or BRCA2 gene is at high risk of developing breast cancer and ovarian cancer in her lifetime.
Traditionally we have focussed on offering BRCA1/2 testing to patients with a strong family history of breast and/or ovarian cancer. However I now believe we should offer information on BRCA1/2 testing to all young breast cancer patients – even if they have no family history.
Clinical benefits of testing young breast cancer patients
If we test a young breast cancer patient without a family history and identify a BRCA1 fault in her blood, that patient’s risk of developing ovarian cancer in the next 20 years can be as high as 35%. We know that ovarian cancer screening does not work well in high-risk women, so we would normally suggest that she considers having her ovaries removed after the age of 40, or when her family is complete, as an insurance policy against her developing ovarian cancer. This strategy is highly effective and will probably save her life from ovarian cancer.
If we test a young lady with breast cancer and no family history, and the test is completely normal, then her risk of developing ovarian is exactly the same as the normal population, and she does not need to consider having her ovaries removed.
The test result always has important implications for the clinical care of that individual patient with breast cancer. It is important to understand that not all genetic testing laboratories offer the same standard of test, and this should be discussed with a specialist who can advise further.
If we identify a faulty BRCA1/2 gene in a patient, she should consider having her ovaries removed, which will probably prevent her developing ovarian cancer; if her gene test is completely normal, then her risk of developing ovarian cancer is the same as anyone else in the population, and she does not need to consider having her ovaries removed.
That is why I believe that all young breast cancer patients, even if they have no family history, should be offered high-quality BRCA1/2 testing. The most important take home message is that I would like to see all young breast cancer patients offered further information on BRCA1/2 testing so they are able to make an informed decision about their ovarian cancer risk.
I am happy to see patients to discuss these options in The London Breast Clinic at 108 Harley Street. I have set up a remote Cancer Genetics clinic operating from108 Harley Street where I can see patients via Skype so they do not need to come in to London to have the consultation.
This article is for information only and should not be used for the diagnosis or treatment of medical conditions. myHealthSpecialist makes no representations as to the accuracy or completeness of any of the information in this article, or found by following any link from this article. Please consult a doctor or other healthcare professional for medical advice.
Dr James Mackay, Consultant Genetic Oncologist