At Longevity Medical Clinic we often talk to our patients about detecting and preventing cancer. It’s something on the minds of most of us, since we all know that, when it comes to treating cancer, early detecting is critical. One of my patients recently asked me about they had read concerning an early detection test for cancer. Are these tests valid, or do they offer a false hope?

In fact, thanks to advances in early detection, there are now some promising tests for cancer. These tests look for what we call “markers” – early signs of cancer.  But the fact is that each cancer has its own specific set of markers, sometimes as many as 30 or 40 that doctors can actually measure. In many cases, in order to get an early detection test that is statistically valid, doctors need to combine 15 or 20 of these markers. You can see how complicated this can get.

Let’s consider one specific example – lung cancer. Almost 5 years ago, medical journals began reporting on the first early detection tests for this dreaded form of cancer. Since 2006 this test has been “fast-tracked” by several different biotech firms, each working to refine this test which looks at six different cancer-related antigens. In terms of sensitivity, this new test is a bit less sensitive than a CT scan; however, the good news is that it can detect tumors that are smaller, and also cancers that are less advanced, giving doctors a head start on treatment options. The new test, called CDT, is also more specific.

But we need to put this into perspective. When doctors perform a CT scan and find a small nodule in the lung, only about 3% will turn out to be cancerous. By contrast, with the newer CDT test, about 10% of the nodules will be cancerous. So the CDT test is indeed a major step forward for accuracy. On the other hand, 90% of CDT-tested patients with suspicious nodules in the lung will turn out to be cancer-free, something they only find out after expensive and invasive lung biopsies.  Some wonder whether this downside, not to mention the fear that comes from waiting for the biopsy results, is worth it. At present this newer CDT test is only being performed on patients at high risk for lung cancer, particularly heavy smokers.

So what’s the conclusion? Well, the fact is that this CDT test is a long way from perfect. However, right now it is the best tool we have available to diagnose early lung cancer in high risk patients.  If you’re wondering about these or other cancer tests, please talk with the staff here at Longevity Medical Clinic on your next visit.