Ready for Your Screen Tests?

Researchers like to be cautious about new technology, and for good reason: Full body scans, for example, can turn up the tiniest anomaly in your arteries and organs. That can lead to invasive testing—and, potentially, treatment—for something that may never have posed a real threat to you. That's why experts wait until studies prove that these technologies actually help diagnose people who are at high risk before recommending their use. Two tests recently qualified: one for heart disease—the leading cause of death for American women—and one for breast cancer, the most commonly diagnosed cancer in women. 

Finding Heart Trouble

Electron beam computed tomography (EBCT) is a noninvasive test that scans your arteries for the presence of calcium deposits. "If there's calcium in the artery, that means there's also cholesterol and plaque that has built up," says Christopher P. Cannon, MD, a cardiologist at Brigham and Women's Hospital and associate professor of Medicine at Harvard Medical School. So the higher your calcium score, the higher your heart attack risk. The cost—typically $300 to $500—isn't usually covered by insurance. (Another screen, the 64-slice CT scan, provides a precise picture of both calcium and plaque in arteries, but it's not yet clear what the results mean for risk.)

EBCT is for people who are at intermediate risk for heart disease; high-risk people don't need further diagnosing, and there's no evidence that the test helps identify future problems in low-risk patients. But consider this screen if you are over 50, postmenopausal, and have one or more risk factors: you are a smoker, overweight, obese, or diabetic, or have high cholesterol, high blood pressure, or a family history of heart disease. Younger patients who have known risk factors but are uncertain whether to take medication may also benefit, says Cannon: "I had one patient who was only 38 years old, but she had a family history of heart attacks and sky-high cholesterol. An EBCT revealed early signs of cholesterol buildup, so I started her on cholesterol-lowering medication."

Detecting Breast Cancer

Breast magnetic resonance imaging (MRI). Cross-sectional images of the breast are produced with electromagnetic waves (instead of the X-rays a mammogram uses). MRI scans can detect breast cancer at its earliest stages. In a five-year study of 7,319 women, German researchers found MRI better diagnosed a premalignant tumor called ductal carcinoma in situ (DCIS) than a mammogram. Among the 167 women who underwent both tests and had DCIS, 92 percent were diagnosed by MRI, 56 percent by mammography.

New American Cancer Society guidelines say the test is only for women at high risk, those with: a BRCA1 or BRCA2 gene mutation or a mother, sister, or daughter who has it; chest exposure to radiation therapy between ages 10 and 30; or Li-Fraumeni, Cowden, or Bannayan-Riley-Ruvalcaba syndromes. High-risk women should get a yearly combination screening of MRI and mammography beginning at age 30. And try to alternate the two screenings every six months to minimize time between tests, suggests David Gruen, MD, a radiologist at Norwalk Radiology and Mammography Center in Connecticut.

Because of the screen's high false-positive rate (it finds cancer when none is present), women with low to average risk are strongly advised against it. Also, their insurance is unlikely to pick up the $1,000 to $2,000 tab.