Test IDs Early Lung Cancer in Smokers
Genetic Test May Help Find Cancer in Smokers in Time for Cure
March 5, 2007 -- A new test tells smokers whether they're getting lung cancer -- with early enough warning to save their lives.
Like current lung cancer tests, the new test requires a bronchoscopy. In that procedure, a doctor inserts a flexible tube through the patient's nose or mouth to examine the lungs for cancerous cells.
But the new test promises to help many patients avoid the far more invasive surgical tests used if a bronchoscopy is inconclusive or can't be done.
From 10% to 15% of smokers get lung cancer.
And more than eight out of 10 people with the disease die within five years of diagnosis. One reason for this high death rate is that by the time doctors diagnose lung cancer, it's usually too late for a cure.
The new test, designed for use in people who smoke, promises to find lung cancers at their earliest stages, say Avrum Spira, MD, and colleagues at Boston University.
The test examines bronchial, or airway, brushings collected during bronchoscopy for 80 genetic changes linked to smoking-related lung cancer.
Currently, bronchoscopy ranges from about 30% to 80% effective in detecting lung cancer.
In contrast, the new test gives doctors a 95% chance of detecting the cancer in smokers. And it offers about a 90% chance of finding the cancer at its earliest, most treatable stage.
If both the test and the bronchoscopy give negative results, it's 95% certain the smoker isn't at immediate risk of lung cancer.
Before the test is ready for prime time, Spira and colleagues say their findings will have to be confirmed by large-scale clinical trials.
Their report appears in the advance online issue of the journal Nature Medicine.