Women are more likely to develop breast cancer if they have mutations in one of two genes. These genes, BRCA1 and BRCA2, are consequently called breast cancer genes. An international team of researchers have investigated whether physical activity in patients with mutations in these two breast cancer genes influences the risk of breast cancer. The results of their study was published in the journal Breast Cancer Research and Treatment.
Indeed, it is already known that sufficient exercise for women from the general population provides protection against breast cancer. On the other hand, the relationship between genetic heredity is less well studied.
For their analysis, the researchers looked at 443 women with altered risk genes BRCA1 and BCRA2 who did not have breast cancer and compared them to women who also had mutations in the two breast cancer genes and subsequently had breast cancer. The women were divided into three groups based on their age: 12 to 17 years old, 18 to 34 years old, and 34 and over. The level of physical activity of the women starting at 12 was recorded using questionnaires. A distinction was made between moderate physical activity and strong physical activity.
Overall, physical activity did not appear to affect women’s breast cancer risk. However, some effects of moderate physical activity at the age of 12 to 17 years on the subsequent risk of breast cancer could be observed. Women who exercised a lot with moderate intensity at that age were less likely to develop breast cancer before their menopause. No correlation could be seen between exercise and cancer after menopause.
Women with mutations in the breast cancer genes BRCA1 and BCRA2, according to the results of the study, can protect themselves from breast cancer, which occurs before menopause, if they exercise at a moderate age in their younger years, ie at the age of 12 to 17 years. As this is an observational study, it that does not allow causal reasoning, the researchers involved in the study are calling for more research on this topic to better assess the effect of physical activity on women at increased risk of breast cancer.