Breast cancer starts when cells in the breast grow out of control. Normally, cells in the body grow and multiply to form new cells as the body needs them. When cells get old or damaged, they die and are replaced. Sometimes, this normal process breaks down. Abnormal or damaged cells grow and multiply when they shouldn’t, forming tumors. Some tumors are cancer, and others are benign (noncancerous).
Breast cancer spreads by growing into, or invading, nearby tissues. If the cancer cells invade nearby lymph nodes or blood vessels, they can travel through the lymph or blood to distant parts in the body. Then they can form new tumors in these places.
Take Charge of Your Health
If you have an abnormal mammogram, breast lump or other breast concern, the breast specialists at Fred Hutch Cancer Center's Breast Health Program can help.
Breast Cancer Risk Factors
Many things can affect the chances that you might develop breast cancer. If you have questions or concerns about your risk level or how to lower your risk, talk with your primary care provider or ask for a referral to the Breast Health Program at Fred Hutch Cancer Center.
The following factors are linked with higher breast cancer risk:
- Being female
- Getting older
- Having a body mass index (BMI) over 30 after menopause
- Having had proliferative breast lesions such as atypia (“proliferative” means there is more cell growth than normal, and “atypia” means the cells look abnormal)
- Having dense breast tissue on mammograms
- Taking hormone therapy for menopause symptoms for more than 4–5 years
- Having your first menstrual period before age 13 or having later menopause (in the U.S., the average age for menopause is 52)
- Having never given birth
- Having your first full-term pregnancy at an older age
- Having already had breast cancer
- Having a family history of breast cancer
- Having a family history of certain genetic mutations (changes)
- Drinking more than four alcoholic drinks per week
- Smoking
- Being exposed to therapeutic ionizing radiation, such as having radiation therapy to your chest or breast
- Taller height
Some of these factors are things you can’t change. But there are others you can control to reduce your risk. There are ways to estimate your individual risk based on many of the above factors.
Learn more about Breast Cancer Prevention.
Genetic Testing for Breast Cancer
Some people develop breast cancer because of genes passed down in their family. Genetic testing uses a blood or saliva sample to look for inherited risks.
You and your care team may want to know if you have an inherited genetic risk. The results may:
- Help those without cancer plan prevention and screening.
- Explain why a cancer happened
- Give information about the chance of developing another cancer
- Help with decisions about treatment
- Find out if your family members are at increased risk for cancer
Health insurance usually covers genetic testing, and low-cost options are also available. Results take 2-3 weeks to complete.
If you had genetic testing in the past that only looked at a few genes, you may need updated testing. It is important to repeat genetic testing over time as our knowledge and technology improve.
To learn more about genetic testing options, ask your medical team to refer you to the clinical genetics team or call 206.606.6990.