In addition to being worried about their own health, survivors who have had breast cancer are often concerned about the health of others in their family. This is a valid concern since their family members, in particular, their sisters, daughters and mothers, do have an increased risk of developing the disease.
How susceptible are you?
In general, the younger a woman is when she develops breast cancer, the more likely it is that another member of her family will develop it too. The risk tends to be highest in families where two or more immediate family members (mother, sister, daughter) have had breast cancer. In these families, the history of breast cancer can usually be attributed to genetic susceptibility.
In some families, genetic risk for breast cancer can be inherited through the father’s side, so relatives on both sides of the family should be well informed about their family history and risks.
The sisters and daughters of survivors who developed the disease at an early age or who are from a high-risk family may want to consider getting tested for mutations in genes linked to breast cancer. The person is known to have had breast cancer usually needs to be tested first. Family members should be aware that the possibility of testing raises many complex issues that should be carefully considered with the help of a skilled genetic counsellor.
What to tell sisters, daughters and mothers
First, the family members should consider seeing a health care provider get their risk of breast cancer assessed. Most women overestimate their risk of breast cancer and are reassured by such an evaluation.
For those who find out that they are at higher risk, the drug tamoxifen may be an option for lowering their risk. In addition, women with a family history of breast cancer should talk to their health care providers about getting screened for breast cancer at an early age. While this will not lower the chance of the disease occurring, it may increase the chance of finding any disease that develops at its earliest, most treatable stage.
Family members should also be told that certain changes in diet and other healthy behaviours can promote overall health and might also help lower their breast cancer risk. Not only may the following behaviours reduce the risk of cancer, but they also protect against other major disorders, such as heart disease and diabetes.