Breast Cancer Prevention
What are the highest risk factors for breast cancer?
With regards to breast cancer prevention, one of the main risk factors for developing breast cancer is exposure to estrogen. For women who start their periods younger than 12, and for woman who go into menopause older than 55, they have an increased risk of developing breast cancer because the breast tissue has been exposed to estrogen over this long period of time. In addition, women who after menopause take hormone replacement therapy have been shown to be at an increased risk for developing breast cancer. There's been some controversy because in the US study, the estrogen and progestin increase the risk of developing breast cancer while the estrogen alone did not increase the risk of developing breast cancer. However, there are European studies which show that estrogen alone does increase the risk of breast cancer. Biologically and intuitively it makes sense that estrogen would increase a woman's risk because we do know that long term estrogen exposure does increase the risk of developing breast cancer. In addition, women who have not had children are at a greater risk of developing breast cancer. Whereas women who have had children after the age of 30 are at a greater risk of developing breast cancer, as well as if they have a family history. Then it starts to get into some of the genetics of breast cancer, women can be born with genetic predispositions to having breast cancer. For instance, BRCA1, BRCA 2 mutations or simply having a relative with breast cancer can increase your risk for having breast cancer. Toxic exposures like alcohol, smoking, radiation to the chest and to the breasts can also increase a woman's risk of developing breast cancer.
What is a "clinical breast exam"?
A clinical breast exam is when your physician examines your breasts, to look for any changes, any lumps or anything concerning for cancer. Clinical breast exams are typically performed once a year, before your screening mammogram, so if there's any abnormalities on exam, they can focus on that area when they do the mammogram. It's important to have your physician examine your breasts, because again, a physician has felt breast cancer before, and most women have not, and so they don't know exactly what feels like cancer and what doesn't feel like cancer. It's true that a woman will pick up changes in her breast earlier than a physician will, but the question is: are those changes necessarily cancer? This is one of the main reasons why the studies looking at breast self-examination have not definitively shown a benefit at preventing cancers or catching cancers earlier.
Is a preventative mastectomy advisable for high risk women?
Whether or not to have a preventative mastectomy is a very individual decision and it comes down to what a woman's risk for developing breast cancer is over her lifetime and how comfortable she is with that risk. There are some women who have BRCA mutations which are mutations that they're born with, that run in their family, that increase their risk of developing breast cancer to about 85% over their lifetime. For most women, that's a high enough risk that they're not comfortable with just increased screening because, even with screening, breast cancer can grow, it can spread. The goal of screening is to catch it early, when it's curable, but when there's such a great risk of it occurring, potentially, getting a bilateral prophylactic mastectomy and removing the breasts before the breast cancer has a chance to occur will decrease her chance of developing breast cancer to just a couple percent, if that. And women who get prophylactic bilateral mastectomies usually can get immediate reconstruction with plastic surgery so that they do not have to live without breasts, and their chance of developing breast cancer is very low.
How is having an abortion and breast cancer related?
They used to think that there was a link between having a miscarriage or an abortion, and having an increased risk of developing breast cancer. However, with more recent trials, that does not appear to be the case. And so it is now believed that there is no link between having an abortion or a miscarriage and developing breast cancer later in life.
