Myth: If you don’t have any risk factors, you won’t get breast cancer.

Truth: The overwhelming majority of women who are diagnosed don’t have any known risk factors. Still, your odds of getting the disease are higher if it runs in your family; if you have never had children or have them after age 30; if you have one or more alcoholic drinks a day; if you started menstruation early or entered menopause late; or if you’re overweight after menopause or sedentary.
What It Means for You: While there’s no sure way to prevent breast cancer, you can reduce your risk by exercising, controlling your weight, and limiting alcohol consumption. Women at high risk should get an annual whole-breast ultrasound or an MRI screening. Those at extremely high risk (they have a strong family history or biopsy results showing atypical cells) should consider taking anti-estrogen drugs, such as tamoxifen and raloxifene.

Myth: The first sign of breast cancer is a painless lump.

Truth: “A lot of women are diligently doing breast exams, thinking they’re looking only for a lump,” says Julie Gralow, M.D., an associate professor of medical oncology at the University of Washington Fred Hutchinson Cancer Center, in Seattle. “They also need to pay attention to any thickening, redness, and asymmetry that develops in the breasts.” In addition, they should look for any changes in the nipples.
What It Means for You: Begin monthly self-exams in your 20s. A full breast exam includes the area around your collarbone as well as both lymph nodes (under each armpit). Keep in mind that 8 out of 10 lumps found are benign. If you feel a lump, says Gralow, it’s most likely a benign cyst (filled with fluid) or a fibroadenoma (filled with dense tissue). But don’t hesitate to have your doctor check any lumps you find.