Sabtu, 25 Desember 2010

Medical Tests That Could Save Your Life

We’ve all heard the scary stories. Someone in his 40s, seemingly in perfect health, suddenly drops dead during his morning run. Or someone we love discovers too late that she has cancer that’s already beyond treatment. And we wonder: Is there anything we can do to make sure this doesn’t happen to us? Yes, there is. Here, five medical tests designed to catch killers like cancer and heart disease before they can do deadly damage.



1. Early CDT-lung test for lung cancer

What it does: Measures autoantibodies the immune system produces in response to lung cancer proteins, known as antigens. These autoantibodies show up early in the cancer process, which gives this test the advantage of being able to detect lung cancer before symptoms appear.



Why it’s important: With an accuracy of greater than 90 percent, this brand-new test is a significant tool for assessing lung cancer risk at an early stage, says pulmonologist Keith Kelly of Paducah, Kentucky, who offers the test to his patients. Lung cancer kills more than 160,000 people a year in the U.S. — and the reason it’s so deadly is that it’s rarely caught early, when tumors are operable. Currently lung cancer still has only a 16 percent five-year survival rate. “With this test as a supplement to CT scan, we can diagnose people earlier and, hopefully, finally begin to improve the survival rate,” says Kelly.

How it works: A sample of your blood is sent to a laboratory, and results are sent to your doctor about a week later. A positive result means the test detected signs your immune system’s been activated in response to the presence of cancer cells. In that case, your doctor will arrange for you to have an imaging scan to search for the presence of tumors. A negative test can’t guarantee that you’re cancer free, but it does mean your body isn’t reacting visibly to the presence of protein-producing tumors.



Cost: $475

Covered by insurance? The CDT-lung cancer test is now covered by the majority of major medical insurers and is also covered by Medicare Part B. The testing company will bill your insurance provider for you.


Who should get it: Long-term smokers and former smokers are at high risk for lung cancer and qualify for this test. Exposure to radon, asbestos, or significant secondhand smoke also puts you in the high-risk category. Oncimmune, the test maker, hopes to have a breast cancer blood test based on the same science available within the next year.



Tests for heart disease and colorectal cancer

2. Corus CAD

What it does: Evaluates your risk for narrowing or blockage in your coronary arteries.



Why it’s important: “To my knowledge, this is the only test that can tell you what’s going on in your arteries at the cellular and molecular level,” says physician Alan Grossman, medical director of the Nuclear Cardiology and Echocardiography Laboratories at the Heart and Vascular Center of Arizona, which this year introduced the Corus CAD test. “Using this test, we’ve found people with severe multivessel coronary artery disease whom we would not have considered at high risk otherwise.”



How it works: A small sample of your blood is sent to the laboratory of the test’s maker, where it’s screened for the presence of 23 genes that have been found to be associated with narrowing or blocked arteries.



Cost: $1,195

Covered by insurance? Some insurance companies cover this test, but many don’t yet. However, the company that makes the test is committed to helping people get coverage, and it provides a patient advocate to help you through the process. And with Time magazine having picked Corus CAD as one of the top-ten medical breakthroughs of 2010, wider adoption and coverage are sure to come quickly.



Who should get it: The most definitive risk factor for a coronary artery blockage is chest pain, particularly chest pain or discomfort that comes on or increases when you exercise. Other risk factors: a family history of heart disease or heart attack.


The company that makes the test, CardioDX, currently offers the test in nine states: Kentucky, Maryland, Illinois, Washington, Wisconsin, Minnesota, North Carolina, Texas, and Arizona. If you don’t live in one of these states, you may have to travel to get the test, or wait a few months. Additional availability is expected in 2011.



3. Virtual colonoscopy

What it does: Uses a computed tomography (CT) scan to image the colon.

Why it’s important: Colorectal cancer, which is cancer of the lower part of the intestines, is the second-leading cause of cancer death in the U.S., yet it’s curable in 90 percent of all cases if caught early. Unfortunately, this still isn’t happening as often as it should; currently almost 40 percent of cases are already stage III or IV when discovered.

Virtual colonoscopies are not only much more comfortable than traditional colonoscopies but eliminate the risk of anesthesia and prevent puncture of the colon. According to Judy Yee, professor and vice chair of radiology at U.C. San Francisco, only 30 percent of people who should be getting colonoscopies actually get them, and increased use of virtual colonoscopy could up that percentage and save lives.



How it works: A computed tomography scanner uses sophisticated software to generate a 3D image of your colon, looking for polyps and cancerous tumors. It takes just 10 to 15 minutes, and the dose of radiation is quite low — about the equivalent of having conventional X-rays taken of the pelvis and abdomen. Because virtual colonoscopy scans the entire abdomen and pelvis, recent studies have shown that it also increases the detection rate for other pelvic diseases affecting the ovaries in women and the prostate in men.



Cost: $500-$1,000

Covered by insurance? Virtual colonoscopy is gaining popularity at major medical centers, but many insurers still consider it experimental and don’t cover it. Medicare doesn’t yet cover virtual colonoscopy but does cover traditional colonoscopy.



Many experts expect this to change, however, now that the American Cancer Society and many other organizations recommend virtual colonoscopy. And some states, including Kentucky, Maryland, and Virginia, now require private insurers to cover the procedure. (That’s also the case in Washington, D.C., where President Obama got his virtual colonoscopy.)



Who should get it: Like colonoscopy, virtual colonoscopy is recommended for anyone over age 50. However, if you have a first-degree family member who’s had colon cancer before the age of 50, it’s recommended that you begin screening when you’re ten years younger than the age at which your family member was diagnosed. If a family member was diagnosed at age 45, for example, you should have your first screening at age 35. Indicators such as blood in the stool are also a reason to have a virtual colonoscopy.


New heart disease test and genetic testing

4. High-sensitivity C-reactive protein test

What it does: Measures even very low blood levels of C-reactive protein (CRP), which is produced by the liver in response to inflammation. CRP is an indicator for cardiovascular disease — among other conditions – - because chronic inflammation damages the interior of artery walls. Because hs-CRP, also called ultra- sensitive CRP or cardio CRP, is sensitive enough to detect lower concentrations of the protein, it can detect inflammation in a healthy person, indicating the early onset of cardiovascular disease.

Why it’s important: This is the first new general screening test for heart disease to be recommended by the American Heart Association in 20 years. The reason: The hs-CRP takes the traditional heart checkup a step further, more accurately predicting who’s at risk for heart attack, stroke, and diabetes. People whose hs-CRP results are in the high end of the normal range have 1.5 to 4 times the risk of having a heart attack than those whose hs-CRP values are at the low end of the normal range. In addition, recent studies demonstrated an association between elevated CRP levels and colon cancer.



How it works: The hs-CRP is a blood test used in concert with other tests, such as a blood pressure check and a lipid profile to check cholesterol and triglyceride levels.



Cost: $40-$70

Covered by insurance? If your doctor recommends the hs-CRP test because you have a family history of heart disease or other risk factors, most insurers, including Medicare, will cover it.



Who should get it: Currently the hs-CRP test is recommended for anyone considered to be at moderate or intermediate risk of developing cardiovascular disease in the next ten years. While hs-CRP isn’t yet considered a screening tool for the general population, an important recent study called the JUPITER study found that hs-CRP predicted heart disease even in people with no risk factors, and some experts now believe everyone in their late 50s and older should have it, even if they have minimal risk factors. The test is simple and inexpensive, and your doctor can order it based on his or her recommendation. So discuss your concerns with your doctor, mention any relatives who had an early heart attack, and you should be covered.

Unfortunately, certain conditions such as arthritis, autoimmune conditions, and chronic infection also cause inflammatory response, so if you have one of these conditions, the hs-CRP test can’t be used.


5. Genetic analysis

What it does: Tests you for approximately a hundred traits, providing a genetic blueprint known as a comprehensive genotype that predicts your risk of developing a variety of conditions and diseases. Genotyping also offers information on how you respond to certain key medications such as blood thinners, and it lets you know if you’re a carrier for certain genetic traits.

Why it’s important: Based on the genetic information you receive, you could find out you’re at risk for certain cancers, Alzheimer’s, macular degeneration, and other conditions. Knowing what may lie in your future makes you more alert for warning signs. In the case of lung cancer, diabetes, and other conditions strongly affected by lifestyle, finding out you’re at risk might increase your motivation to make important changes, such as losing weight or quitting smoking — or to take specific tests to detect a condition early enough to treat it. In this case, knowledge really is power: Knowing you’re at risk empowers you to take steps to protect yourself.


How it works: Personalized genotyping is done by saliva testing. Your saliva sample is collected in a tube and shipped off to a sophisticated genetic testing laboratory that analyzes your DNA. The results are ready in two to three weeks, at which point you’re given access to a comprehensive report and interactive genetic counseling via a secure online account. The testing kits are provided by private companies, which include 23andme, Navigenics, and Pathway Genomics; each company then provides its own ongoing health management service.



Cost: Varies, depending on the company and the extent of the services provided. You can pay for the initial testing only, then be billed for regular monthly reports and genetic counseling; or you can pay upfront for the comprehensive service. Range is $99 plus a $5-per-month subscription access fee with a 12-month commitment, or $399-$499 for full-service access.



Covered by insurance? Insurance doesn’t cover this type of comprehensive genetic analysis. However, if you have a health savings account or a flexible spending account for healthcare, you’ll likely be able to use those dollars to purchase a genotyping service and submit it for reimbursement. Check with the administrator or benefits specialist to find out.



Who should get it: Anyone concerned about their genetic risk for health conditions such as cancer, macular degeneration, heart disease, and diabetes, particularly those already at risk due to family history or from other risk factors. If you smoke, for example, knowing your genetic risk of lung, breast, and colorectal cancer could be extremely useful. And if you carry a lot of extra weight, you might want genetic information to better evaluate your risk of diabetes and heart disease.

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