DEAR DOCTOR K: I'm a longtime smoker. Do I need to be screened for lung cancer even if I don't have any symptoms?
DEAR READER: Until recently, my answer would have been "no." In the not-too-distant past, screening of people without symptoms -- even smokers who were at high risk -- was judged useless for lung cancer. That's because screening for lung cancer involved using standard chest X-rays, and they produced too many "false positive" results: They identified "spots" in the lungs that were harmless.