Risk Factors and Symptoms of Breast Cancer

Risk Factors

Certain factors may increase the chance of developing breast cancer, though these factors do not directly cause cancer. Some people with multiple risk factors never develop breast cancer while others who do not have any risk factors do develop breast cancer. Although some risk factors cannot be changed, such as a person’s age or family history, there are some things you can do to help lower your risk, such as maintaining a healthy weight, being physically active and limiting alcohol consumption.

The average woman has approximately a 12 percent chance of developing breast cancer. About 10 to 15 percent of breast cancers are driven by genetic factors while the remaining are referred to as sporadic and risk is contributed to by a variety of factors.

Early detection is important, so be sure to talk with your doctor about potential risk factors. They include:

• Being female is the most important risk factor for breast cancer. Although men can get breast cancer, it is about 100 times more common in women.
• Being older because most breast cancers occur after the age of 50.
• Family history of breast, ovarian or prostate cancer may cause you to be two to three times more likely to develop breast cancer.
• Inherited gene mutations have been linked to breast cancer. These include mutations in the following genes: BRCA1, BRCA2, p53, CHEK2, ATM and PALB2. Other genes are under study and may also play a role in breast cancer.
• Ashkenazi Jewish heritage poses a slightly higher risk of breast cancer than other women. This increased risk is likely due to the high incidence of BRCA1 and BRCA2 gene mutations in Jewish women of Eastern European descent (Ashkenazi Jews).
• Radiation exposure to the chest area in adolescence or early adulthood (before age 30) increases the risk of breast cancer. This includes radiation treatment to the chest area for childhood cancer, treatment of other cancers such as lymphoma, as well as radiation to treat acne or enlarged thymus glands.
  • The amount of radiation from a mammogram is very small and does not increase your risk of getting breast cancer.
  • Very low doses of radiation (such as from X-rays and other medical imaging), when used appropriately, do not impact breast cancer risk.
• Age at first period or at menopause is important because if you began having menstrual periods before age 12 or went through menopause after age 50, your risk for breast cancer is slightly higher than that of the average woman. It is thought that this is due to the amount of the female hormone estrogen to which your breasts have been exposed over your lifetime.
• Age at first pregnancy (after age 30) or never having children puts you at a slightly higher risk. This may be due to the protective changes in breast tissue that occur with full-term pregnancies.
• Hormone replacement therapy after the beginning of menopause slightly raises your risk of breast cancer. This added risk disappears about three to five years after you stop taking the hormones. The risk is greatest for combination hormone replacement therapy, which uses both estrogen and progestin, as opposed to therapy using estrogen alone.
• Atypical hyperplasia refers to extra cells that grow in an abnormal pattern in the ducts (atypical ductal hyperplasia) or lobules (atypical lobular hyperplasia). Both are linked to an increased risk for developing breast cancer. If atypical hyperplasia is identified in a biopsy, surgery may be recommended.
• Lobular carcinoma in situ (LCIS) is characterized by an increase in the number of cells confined inside breast lobules, the milk-producing glands. LCIS is not breast cancer but does increase risk and necessitates regular screening.
• Women with extremely dense breasts on mammograms are four to five times more likely to get breast cancer than women with fatty breasts on mammograms.
• Being overweight or obese increases your risk of breast cancer. It also increases the possibility that breast cancer will return after treatment, particularly after menopause.
• Consuming more than one alcoholic drink per day on a regular basis has a higher risk of breast cancer than non-drinkers.

If you are interested in learning about your risk for developing breast cancer, our Breast Cancer Personalized Risk Assessment, Education and Prevention (B-PREP) Program offers an in-depth risk survey along with screening, genetic counseling, and education about prevention strategies.

Learn more about risk factors.

Symptoms

Patients with early-stage breast cancer generally do not show symptoms. Most symptoms develop when the cancer has grown. Symptoms may include:

• A new lump or mass (although most breast lumps are not cancer)
• Swelling in or near your breast or under your arm
• Skin dimpling
• Nipple discharge that may be bloody or clear and only in one breast (not breast milk)
• New nipple inversion/retraction (turning inward)
• Change in the size/shape, look (e.g., dimpled, puckered, red or purple) or feel (e.g., itchy or scaly) of your breast or nipple

Speak with your doctor if you are experiencing any new, unexplained or changing symptoms. These symptoms can have other causes, many of which are non-cancerous. Although having symptoms does not mean you have breast cancer, it is important to discuss any health concerns with your doctor who can help address your concerns and check for those other possible conditions as well as for breast cancer.

Learn more about symptoms.