Breast Cancer Can Run In The Family: Genetic Screening Can Help Determine Your Risk

About 5% to 10% of breast cancer cases are thought to be hereditary. Read on to know more about Hereditary Breast and Ovarian Cancer Syndrome.

Hereditary Breast and Ovarian Cancer Syndrome (HBOC) is considered when there are multiple cases of breast and/or ovarian cancer in the family. Any of the following circumstances increase the likelihood of having HBOC:

• Multiple generations in the family have breast and ovarian cancers
• A woman who has second breast cancer, whether in the same or a different breast, or who experiences breast as well as ovarian cancer.
• Breast cancer in a male relative.
• There is a family history of contribution of breast cancer, ovarian cancer, and prostate cancer
• Two or more relatives with breast cancer underage of 50
• Three or more relatives with breast cancer at any age

What Causes HBOC?

It is a genetic condition that is passed down through families. This means that a family's cancer risk is passed down from generation to generation. BRCA1 and BRCA2 are the two main genes associated with the majority of HBOC families. BRCA 1 & BRCA 2 are tumour suppressor genes. Any variation in BRCA 1 & BRCA 2 genes are associated with female breast cancer. A BRCA1 or BRCA2 "mutation," or harmful genetic change, increases a woman's lifetime risk of developing breast and ovarian cancer.

Men who have these gene mutations are also at a higher risk of developing breast cancer and prostate cancer. People with BRCA1 or BRCA2 mutations are also at slightly increased risk of developing other cancers, such as pancreatic cancer and melanoma.

Experts have estimated the levels of breast cancer risk associated with each gene mutation based on current research. Genetic risk levels are divided as:

High risk: The lifetime risk of breast cancer is estimated to be greater than 50%.

Moderate to high risk: Estimates of lifetime breast cancer risk range from 25% to more than 50%.

Moderate risk: The lifetime risk of breast cancer is estimated to be between 25% and 50%.

Uncertain risk: While research studies have found insufficient evidence to link the mutation to an increased risk of breast cancer, it has been linked to an increased risk of ovarian cancer and possibly other cancers.

Genetic testing for breast and ovarian cancer risk

The BRCA gene test can help identify mutations in BRCA1 and BRCA2. The blood test is often performed on those who are likely to inherit mutations in these genes based on personal or family history of breast cancer or ovarian cancer. If the result comes positive, which means you are carrying a gene mutation that increases your risk of cancer, you can work with your doctor to manage that risk. But the results aren't always clear as the test may also detect a gene variant that doctors aren't certain about.

Risk factors for breast cancer

Let's look at some of the major risk factors for breast cancer.

Being a female

This is the most essential risk factor for breast cancer. Men can develop breast cancer, but it is much more common in women than in men.

Growing older

As you age, the chances of developing breast cancer increase. Most breast cancers are found in women after they age 50 or more.

Genetic factors

About 5% to 10% of breast cancer cases are thought to be hereditary, which means they are caused by gene changes (mutations) passed down from a parent.

Women who have close blood relatives with breast cancer, are at a higher risk:

A woman's risk of developing breast cancer is nearly doubled if she has a first-degree relative (mother, sister, or daughter) who has the disease. Her risk is roughly tripled if she has two first-degree relatives.

Women who have a father or brother who has had breast cancer are also at an increased risk of developing the disease.

Menopause after the age of 55

Women above the age of 55 who have had more menstrual cycles because of entering menopause later in life have a slightly higher risk of breast cancer. Their greater lifetime exposure to the hormones estrogen and progesterone may be to blame for the increased risk.

The article is contributed by Dr Kavya Krishnakumar, Consultant Obstetrics & Gynaecology, Motherhood Hospital, Chennai.