Imagine discovering that you carry a BRCA gene mutation after a close relative develops breast cancer. It is natural to wonder whether you are next.

However, inheriting a genetic mutation associated with breast cancer is not the same as having breast cancer. The result indicates an increased susceptibility to the disease, not a certainty that it will develop.

Understanding this distinction is an important first step towards making informed decisions about your health.

Key Takeaways

• Carrying a harmful BRCA1 or BRCA2 gene mutation increases your risk of breast cancer, but it does not mean you will inevitably develop the disease.
• Your personal risk depends on several factors, including your age, family history and the specific genetic variant.
• Genetic testing for breast cancer can help identify inherited risks and inform decisions about screening and risk reduction.
• A positive result does not automatically mean you need preventive surgery.
• Genetic counselling can help you understand your results and consider the options available to you.

What Does a BRCA1 or BRCA2 Mutation Actually Mean?

BRCA1 and BRCA2 are genes that help repair damaged DNA and maintain normal cell function. Certain harmful variants in these genes can interfere with this process, increasing the likelihood of particular cancers.

Everyone has BRCA1 and BRCA2 genes. The concern arises when someone inherits a pathogenic variant, which affects how the gene functions. These variants can increase the risk of,

• Breast cancer.
• Ovarian cancer.
• Other cancers, including certain prostate and pancreatic cancers.

A BRCA mutation can be inherited from either parent. Having a father with no history of breast cancer, for example, does not rule out an inherited risk.

If I Have the Mutation, How Likely Am I to Develop Breast Cancer?

A positive result does not provide a definite prediction of your future health. People with harmful BRCA variants have a higher lifetime risk of breast cancer than the general population. 

However, not everyone with a mutation develops cancer. Your individual risk may be influenced by,

• The specific variant- BRCA1 and BRCA2 variants can be associated with different patterns of cancer risk.
• Your age- Risk changes over a person’s lifetime.
• Your family history- The ages at which relatives developed cancer and the types of cancer in the family can provide additional context.
• Other individual factors- Your broader medical and reproductive history may be relevant when discussing risk management.

This is why a genetic result should be discussed alongside your personal circumstances rather than viewed in isolation.

What Can Genetic Testing for Breast Cancer Tell Me?

Genetic testing can help determine whether you carry certain inherited variants associated with an increased risk of breast cancer.

Testing may be considered when someone has a strong family history of breast or ovarian cancer, a relative with a known pathogenic variant, or other clinical features suggesting an inherited cancer predisposition.

The process generally involves a blood or saliva sample, depending on the test. So, results may fall into three broad categories,

• Positive- A pathogenic or likely pathogenic variant has been identified, indicating an increased risk of certain cancers.
• Negative- No relevant variant was detected. However, this does not eliminate breast cancer risk, particularly if there is a significant family history.
• Variant of uncertain significance- A genetic change has been found, but there is insufficient evidence to determine whether it increases cancer risk.

A variant of uncertain significance should not automatically be treated as a cancer-causing mutation. Its interpretation may change. Hence, genetic counselling before and after testing can help you understand these distinctions and their implications for your family.

Does a Positive Result Mean I Need Preventive Surgery?

Not always. A positive BRCA result creates an opportunity to discuss risk management before cancer develops. 

The appropriate approach depends on your estimated risk, age, medical history and personal preferences. Some options may include,

• Enhanced breast surveillance- Your doctor may recommend a tailored screening schedule involving breast MRI, mammography or both, depending on your circumstances.
• Risk-reducing medication- Certain medicines may be considered in selected individuals after discussing their potential benefits and risks.
• Risk-reducing surgery- Some people may consider removing breast tissue to reduce their risk. This is a significant decision that requires careful discussion of the benefits, limitations and consequences.

These approaches are not interchangeable, and no single option is appropriate for everyone.

For some people, surveillance is the preferred approach. Others may wish to discuss preventive surgery. The decision should follow an individual assessment rather than being based on the genetic result alone.

Frequently Asked Questions 

Can I develop breast cancer even if my BRCA test is negative?

Yes. Most breast cancers are not caused by inherited BRCA1 or BRCA2 mutations. A negative result does not eliminate the possibility of developing breast cancer.

Should I get tested if breast cancer runs in my family?

It may be appropriate, particularly if several relatives have had breast or ovarian cancer, a relative developed cancer at a young age, or a family member has a known pathogenic variant. A clinical assessment can help determine whether testing is suitable.

Can men carry and pass on BRCA mutations?

Yes. Men can inherit and pass on BRCA variants to their children. These variants can also increase the risk of certain cancers in men.

If I carry a BRCA mutation, should my children be tested?

A harmful BRCA variant can be passed from a parent to a child, with each child having a 50% chance of inheriting it. The appropriate timing of testing depends on the circumstances and should be discussed with a genetic counsellor or doctor.

Does a BRCA mutation affect both breasts?

It can increase the risk of cancer in either breast and may increase the risk of developing a new cancer in the opposite breast after an initial diagnosis. However, the individual risk varies, and a mutation does not mean that cancer will necessarily develop in both breasts.

Schedule a Consultation to Understand Your Risks

A BRCA mutation can be an important piece of information, but it does not determine your future on its own. Understanding your genetic results, family history and screening options can help you make informed decisions about managing your risk.

If you have a strong family history of breast or ovarian cancer, or have received a positive genetic test result, consider discussing your circumstances with a breast specialist.

At Radhika Breast and General Surgery, Dr. Radhika Lakshmanan can assess your concerns and discuss appropriate next steps based on your individual circumstances. Consider arranging a consultation to understand your breast cancer risk and the screening or risk-management options that may be suitable for you.