Health Tests to Get, and Tests to Skip

Find out which tests the experts recommend, and which ones are not worth your time and money.

By Susan Ince

Body ScansMost experts don’t recommend full-body scans. When it comes to body-part specific CTs, the evidence is mixed:Heart Scans: Two types of CT scans, electron-beam tomography and multi-slice CT, measure the amount of calcium-containing plaque built up in your coronary arteries. The American Heart Association currently endorses heart scans only to help plan preventive strategies in individuals with a moderate or uncertain risk.Virtual Colonoscopy: The technique (when done with the latest tools) recently proved as accurate as the traditional method. But it may not seem so virtual once you’ve cleaned out your colon and had a tube stuck up your rectum. Participants in one study rated regular colonoscopy as less painful (perhaps thanks to sedatives). And because any polyps found must be removed via standard colonoscopy, the newer method probably won’t be recommended for high-risk individuals.Lung CT: Standard chest x-rays haven’t been shown to save lives; trials are under way to determine whether low-dose CT scans can do any better. A 1,520-person study detected 38 cancers — but to diagnose them, the doctors had to investigate suspicious nodules in 1,049 people. Of those nodules, 98 percent were benign, but additional tests and sometimes a biopsy were needed to rule out cancer.Weighing the Radiation RisksDon’t underestimate your exposure.

  • BONE-DENSITY SCAN = 2 days of average environmental radiation (from radon gas, cosmic rays, etc.)
  • CHEST X-RAY = 10 days of environmental radiation
  • DENTAL X-RAYS = 19 days of environmental radiation
  • MAMMOGRAM = 3 months of environmental radiation
  • HEAD CT SCAN = 8 months of environmental radiation
  • FULL-BODY SCAN = 3 years of environmental radiation

Compiled by Erin SzetoTests to GetRecently introduced tests promise to make screening for certain cancers less invasive and more precise. Can they deliver?Ovarian CancerThe two tests currently used to screen for ovarian cancer — transvaginal ultrasound and a blood test for a protein called CA-125 — are so imperfect that they aren’t recommended unless a woman is at high risk. Coming this year: Correlogic’s OvaCheck, a blood test that detects telltale protein patterns associated with ovarian cancer. The science behind OvaCheck is from the burgeoning field of proteomics, which enables scientists to visualize thousands of small proteins, making it possible to design detection for diseases not linked to a single change in a gene or protein. In one study, OvaCheck had no false negatives or positives; in the real world, it’s expected to be effective but exact specificity hasn’t been established.Cervical CancerWhile a traditional Pap smear screens for cells that have already turned abnormal, a new test, Digene’s DNAwithPap, also looks for high-risk strains of human papilloma virus (HPV) — the virus that causes nearly all cervical cancers. Not everyone with HPV will get cancer (in younger women, the sexually transmitted virus is common and often disappears on its own). But in a study of more than 11,000 women, DNAwithPap was better than a Pap smear at identifying women over 30 with cervical cancer or precancerous changes, and it’s now FDA approved for this purpose.Bladder CancerDiagnosis of bladder cancer in women may be dangerously delayed because early symptoms, such as blood in the urine and needing to urinate frequently, sometimes mimic perimenopausal complaints. To diagnose cancer, doctors must insert a scope through the urethra into the bladder. A urine sample can also be examined under a microscope, but by itself this misses about 70 percent of cancers. Now, a new urine test — Matritech’s BladderChek — can improve the accuracy of cytoscopic testing. The 30-minute test detects four times as many early cancers as cytology. Colon CancerThe least-invasive colon-cancer test, which checks a stool sample for blood (a sign of advanced cancer), now has a pricey ($795) but more-precise competitor. PreGen-Plus from Exact Sciences checks stool for mutated DNA shed by colon tumors. According to a study presented in October, PreGen-Plus detected 52 percent of the earliest-stage colon cancers, making it four times as sensitive as fecal occult blood testing.Tests to SkipIf you want tests with clear evidence of value, skip these. Despite the hype, most women won’t be helped.The Breast "Pap"Ductal lavage, sometimes described as a Pap smear for the breast, flushes out cells from the lining of the milk ducts, where many cancers originate. The innovative concept was greeted with enthusiasm, and some studies seemed to show that women with abnormal duct-fluid cells were at heightened risk of breast cancer. However, in a study published by Memorial Sloan-Kettering researchers, the technique found no clearly cancerous cells in the ductal fluid of 20 women known to have breast cancer. For now, the test only makes sense for women who want to participate in studies of the technique in conjunction with standard tests.Bone Densitometry in PerimenopauseUnless you’re already menopausal or have other risk factors for osteoporosis (such as prolonged steroid use or a strong family history of the disease), measuring bone-mineral density in your 40s makes little sense. "If your results are a little low, you’ll be alarmed, but nobody knows whether it predicts later problems or whether you’d benefit from medication," says Rhoda Cobin, MD, past president of the American Association of Clinical Endocrinologists. You’ll likely be told to take the same bone-protective measures as someone who never took the test: Exercise and get plenty of calcium. Originally published in MORE magazine, May 2004.

First Published Mon, 2009-04-06 18:08

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