Prior Breast Cancer Diagnosis
A personal history of breast cancer increases by three- to four-fold the chances of a getting a new breast cancer either in another part of the same breast or in the opposite breast. This risk for a second breast cancer is different from the risk of recurrence of the original cancer.
Direct Family History
Having a mother, sister, or daughter (“first-degree” relative) who has been diagnosed with breast cancer roughly doubles your risk for the disease, and having two first-degree relatives with breast cancer increases the risk by about five-fold. The risk is greater if your relative(s) developed breast cancer before menopause and/or had cancer in both breasts. Having a male blood relative with breast cancer also increases a woman’s risk of the disease.
It should be noted that 87% of women diagnosed with breast cancer do not have a direct family history – thus, all women should be aware of other risk factors and screening guidelines. At the same time, a direct family history does not guarantee that you will get breast cancer: Three-fourths of women with a family history do not develop the disease.
High-Risk Breast Lesions
Breast atypia (abnormal cells) and lobular carcinoma in situ (LCIS) are two benign (non-cancerous) conditions that may be found by a needle or surgical biopsy. Women with a history of a breast biopsy showing atypia or LCIS are four to five times more likely to develop breast cancer than the average woman. Women with breast atypia or LCIS typically are offered more intensive breast cancer screening, such as twice-a-year breast exams and, in some cases, MRIs in addition to yearly mammograms. While there is no need for radiation or chemotherapy since these are benign conditions, taking an oral anti-estrogen medication such as tamoxifen or raloxifene may be recommended to decrease breast cancer risk.
Being overweight (body mass index higher than 25) or obese (body mass index higher than 30), especially after menopause, increases risk for breast and certain other cancers. Certain body types are also associated with higher risk – for example, women who carry more fat in the waist area (apple-shaped). Losing weight is an important step to lowering your breast cancer risk. For more information on how to calculate your body mass index and weight loss, please click here.