Is DCIS breast cancer hereditary?
Only about 5-10% of all breast cancers are hereditary. However, because your sister is so young there is concern for the possibility. You do not mention your age or which family members had cancer or how old they were at diagnosis. The answers to these questions also help determine the likelihood. It also helps to know if any were males or if anyone had ovarian cancer. I’m sure your sister’s oncologist will be going over all of this with her. They should have your sister tested to see if she has one of the BRCA genes. It is much easier and less expensive to check a known cancer patient.. If she tests positive then you should also be tested. If she tests negative than you do not need to be tested, as it is not hereditary. However, even if it is not hereditary you would still be at a higher risk for breast cancer and therefore you should begin screening now. Screening is not normally recommended for women until the age of 40 so if you are younger than 40 be clear with your doctor about y
