- Breast density. The study concludes that all women should have a screening mammogram at age 40 to check the density of their breasts.
Density is directly linked to breast cancer risk, which rises as density increases although the reasons are unclear. The size and shape of breasts don't provide a clue; density describes the relative amount of different kinds of tissue present in the breast. As breast density goes up, so does the risk of cancer. Women with extremely dense breasts have a substantially higher risk of cancer than women with mostly fatty breasts.
One widely used measure to assess density is the American College of Radiology's BI-RADS rating scale of 1 to 4. In the scale 1 is mostly fatty and 4 is extremely dense. Radiologists routinely note this information on mammogram results. Patients receive a written summary of findings and doctors get a technical report. If the summary you receive doesn't contain this information, ask your doctor where you are on the spectrum. "Second to age, breast density is the strongest risk factor," Kerlikowske says. "Women should know their breast density score."
- Breast biopsy. Women who have had a biopsy that reveals noncancerous changes in breast tissue may have an increased risk of developing breast cancer. These changes can include abnormal cells in the breast ducts or milk-producing sacs, benign (noncancerous) lumps, and benign cysts. "When you do a mammogram, you may see something that should be biopsied," says Kerlikowske. "Although it's not cancer, there's some underlying process going on that increases the risk. It's a marker." Even if the tissue turns out to be completely normal, the chances of developing cancer go up.
- Family history. A woman's risk of breast cancer doubles if she has a "first-degree" relative — mother, daughter, sister — who has been diagnosed with breast cancer. Two first-degree relatives with breast cancer increase the risk fivefold. Aunts and grandmothers don't count as first-degree relatives.
Next: Personalize your own screening plan with your doctor. >>