Can I inherit breast cancer in the family, and should I get tested?

Breast cancer can indeed be hereditary. Roughly 10 to 15 percent of all breast cancer cases have a hereditary cause. The most well-known culprits are mutations in the genes BRCA1 and BRCA2. A single faulty copy is enough to raise the risk significantly, because the abnormal gene is inherited as a dominant trait. Besides BRCA1 and BRCA2, other genes also increase the risk: some substantially (such as TP53, PTEN and CDH1), others to a lesser but still clinically relevant degree (such as ATM, CHEK2 and PALB2).

Whether breast cancer in your family may be hereditary depends on a few recognisable signs. Have several cousins, aunts or uncles, parents or grandparents on the same side of the family died of breast or ovarian cancer? Was anyone younger than 36 when they received the diagnosis? Did anyone have cancer in both breasts? Or are there also cases of prostate, pancreatic or stomach cancer in the same branch of the family? The more signals of this kind, the greater the likelihood that a hereditary mutation is involved.

Getting tested then has real benefits. If you know you carry a mutation, doctors can adjust your screening, for example with an annual breast MRI. If symptoms are already present, a confirmed BRCA1/2 mutation can also change the treatment: there are medicines that work specifically in people with such a mutation, by preventing cancer cells from repairing their damaged DNA. In serious cases, preventive surgery may also be considered.

Before undergoing a genetic test, you first consult a genetic counsellor. They use questionnaires and calculation models to estimate how likely you are to carry a hereditary mutation, so that testing is targeted and meaningful. Commercial panel tests that examine many genes at once have become more affordably available, but not every abnormality found immediately yields clear advice. Some findings remain ambiguous, particularly for genes whose clinical significance for your population group has not yet been well mapped. That makes guidance from a specialist indispensable.