Mathematical models can be used to determine your risk for developing breast cancer. Using a model available through the American Society of Breast Surgeons, and entering the following information provided by you, your surgeon can calculate how likely it is that you will develop breast cancer in the next 5 years, as well as in your lifetime.
The information needed includes:
Your personal history of cancer, including the specific type(s) of cancer(s)
and your age at the time the cancer was diagnosed.
Your family history of cancers, including the specifics of each family
member’s cancer(s) and their age at the time of diagnosis.
Your Height and Weight.
Your age at first period (menses).
Your age at first pregnancy.
Your age at menopause.
Whether or not you still have your ovaries.
Whether or not you have used hormones.
.... and if you used hormones, which hormones you took and for how long.
The number of breast biopsies you have had, and the results of the biopsies (specifically if any showed atypia or lobular carcinoma in-situ).
If you are found to be at a 20% or higher chance of developing breast cancer in your lifetime, your physician will discuss screening breast MRI with you. If you are found to be at a 1.7% or higher chance of developing breast cancer in the next 5 years, your physician may offer to prescribe one of the following medications:
- Tamoxifen—Taken daily for 5 years will decrease a woman’s risk of developing breast cancer (invasive breast cancer and noninvasive breast cancer) in her lifetime by half (50%). Tamoxifen may be taken by women who are still having menstrual cycles, as well as women who are menopausal. Tamoxifen does have the potential for undesirable side effects, including hot flashes, menopausal symptoms, weight gain, blood clots, and uterine cancer.
- Raloxifene—May be used by women who are menopausal. Raloxifene taken daily for 5 years will decrease a woman’s risk of developing breast cancer in her lifetime by 40%. Raloxifene has an added benefit of helping osteoporosis but can also cause blood clots.
Your physician can tell you if you are a candidate for either of these medications that may be used to prevent breast cancer.