Risk Factors & Prevention
And you are at higher risk of getting a NEW breast cancer compared to someone else who has never had the disease.
Family history: Breast cancer in your family can have a significant impact on your risk. But this doesn't ALWAYS mean that you are at high risk just because someone in your family had breast cancer. For example, if your grandmother was diagnosed with breast cancer at age 75, this may not increase your risk of the disease. Your grandmother was most likely just 1 of the 13 women who gets breast cancer between the ages of 60 and 79.
Certain breast changes: Normal breast cells can sometimes get overexcited and start to misbehave. These changes can show up as a lump, thickness, or calcifications on a mammogram. If a biopsy is done, these changes can be seen under a microscope. When the breast duct cells are overactive and appear unusual, the pathology report may describe these findings with the term atypical ductal hyperplasia . An uncontrolled growth of breast cells in the lobule (the part of the breast that makes milk) is called lobular carcinoma in situ or LCIS . (Even though the word “carcinoma” is part of the term LCIS, it is not considered a true cancer.). These two types of breast changes are associated with an increased risk of breast cancer in the future. But these abnormalities are not themselves cancerous.
Genetic alterations : To date, most inherited cases of breast cancer have been associated with two genes: BRCA1, which stands for BReast CAncer gene one, and BRCA2, or BReast CAncer gene two. The function of these genes is to keep breast cells growing normally and to prevent any cancer cell growth. But when these genes contain abnormalities, or mutations, they are associated with an increased breast cancer risk. Abnormal BRCA1 and BRCA2 genes may account for up to 10% of all breast cancers. Women diagnosed with breast cancer who have an abnormal BRCA1 or BRCA2 gene often have a family history of breast cancer, ovarian cancer, or both. There are also women with a strong family history of breast cancer who might have another kind of genetic abnormality that's not yet been identified. But it's also important to remember that most women with breast cancer have no significant family history of the disease.
Menstrual history: You have no control over the amount of estrogen that your ovaries produce over time. If you were very young when you got your first period, or you had a late menopause, or both, you have had more years of exposure to estrogen and other hormones produced by your ovaries. Women who had their first period before they were 12 years old or went through menopause after 55 have a higher risk of breast cancer than women with fewer years of exposure to hormones made by the ovaries.
Race: Breast cancer in the United States occurs more often in white women than Latina, Asian, or African American women. But in women 40 and younger, African American women have the highest risk.
Radiation therapy to the chest before you were 30 years old: If you had radiation therapy to your chest before you were 30 years old and particularly during adolescence, you may have a higher risk of developing breast cancer. This has been seen in young women receiving radiation to treat Hodgkin's disease. (This does NOT include radiation therapy to treat breast cancer.)
Breast density: Past research has shown that women with “dense” breasts, which contain more glandular and connective tissue, are more likely to be diagnosed with breast cancer than women whose breasts are less dense (mainly made up of fat tissue). Breast cancer itself is dense and starts from glandular tissue. Estrogen makes breast tissue more dense. So the connection between breast density and breast cancer may be related to higher levels of estrogen in the body. On a mammogram, a cancer is harder to spot in dense tissue than in fatty tissue. That's because the cancer looks a lot like the glandular tissue around it.
Exposure to DES (diethylstilbestrol): DES is an estrogen-like hormone used in the past to help women prevent miscarriage. Daughters of women who used DES have an increased risk of cancer of the vagina. This drug may also increase the risk of breast cancer in women who used it and in their daughters who were also exposed to it.
Late pregnancy or no pregnancy: Women who had their first full-term pregnancy after age 30 and women who never had a full-term pregnancy are at higher risk for breast cancer than those who gave birth earlier in life. A full-term pregnancy, which stops your menstrual cycle for nine months, seems to offer protection against breast cancer.
If you weigh uncontrollable factors against those that CAN be changed, you'll see that you can do a lot to lower your risk of breast cancer. And while it's very hard to pin down specific foods or chemicals that are firmly linked to a higher or lower risk of breast cancer, researchers are working hard to find out whatever they can about specific lifestyle and environmental factors that may be within your control.