The exact cause or causes of triple-negative breast cancer are unknown, but researchers have linked it to mutations in the BRCA1 and BRCA2 genes. They also have been able to identify certain risk factors, such as being premenopausal or having obesity, that increase your odds of getting this cancer. Some risk factors are within your control to change, and some are not.
Triple-negative breast cancer (TNBC) is a type of cancer that doesn’t use hormone receptors, such as estrogen, progesterone, or HER2, to grow.About 15%-20% of all breast cancers are categorized as triple negative. Because the cancer cells lack hormone receptors, patients have fewer treatment options.
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Potential Causes
When a breast cancer patient tests negative for progesterone receptors, estrogen receptors, and human epidermal growth factor receptors (HER2), the cancer is identified as “triple-negative” breast cancer.
Triple-negative breast cancer has been linked to mutations in breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2). These genes normally help produce proteins in the body that help suppress tumors.
But just because an association has been confirmed doesn’t mean that the gene mutationcausesthe cancer. Based on statistics, however, researchers know that there is a strong relationship.
About 10% to 20% of all people with triple negative breast cancer test positive for a BRCA1 or BRCA2 gene mutation.
Some studies, however, have linked other gene mutations to this cancer, including BARD1, PALB2, and RAD51D. These are genes that are involved in a specific type of DNA repair.
Researchers steer clear of identifying a causal relationship between the mutations and the cancer but suggest that women with variations in those genes may benefit from improved screening, risk management, and cancer prevention strategies.
Risk Factors
Risk factors are characteristics that increase your likelihood of getting a disease, but they do not cause the disease. Some risk factors for triple-negative breast cancer are modifiable, such as whether or not you choose to smoke, while other risk factors, like age, are out of your control.
Risk factors fortriple-negative breast cancerinclude:
Remember that risk factors don’t directly cause cancer. Just because you fall into a particularly high-risk category doesn’t mean that you will get triple-negative breast cancer. However, knowing about your risk factors can help you to make decisions about screening or potentially lowering your risk with certain lifestyle changes.
Prevention
While you can’t change your genetic makeup or your age, there are a number of lifestyle factors you can change when it comes to decreasing your risk for triple-negative (and all) breast cancers.
To reduce your risk for cancer, consider:
You might also ask your provider about finding hormonal birth control or hormone replacement therapy alternatives if you have other significant risk factors for TNBC. Your healthcare provider can outline the risks and benefits of each method so that together you can find the best fit for your lifestyle and health.
However, surgery is a significant step that carries its own risks. If you are concerned about your risk for triple-negative breast cancer, discuss your options with your provider.
Summary
The cause or causes of triple-negative breast cancer are still unknown, but risk factors have been identified. Having one or more risk factors won’t necessarily mean that you willget triple-negative breast cancer,and not having any risk factors doesn’t mean it’s impossible to get triple-negative breast cancer.
The best thing you can do to protect yourself is to follow a healthy diet and exercise regularly. Stay on top of your breast health, throughself-exams at home. Have your healthcare provider give you a breast check during your annual exam and regularly schedulemammogramsas recommended for your age.
11 Sources
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