Chest x-rays were used for many years as a screening test for lung cancer, but studies eventually found that they were ineffective. Then, a 2006 study showed that low-dose CT screening in smokers significantly lowered the rate of death from lung cancer, but the study came under a cloud of suspicion when it was revealed that the study's primary funder and principal investigator had tobacco industry ties. Yet, in 2008, a federally-funded randomized controlled trial largely confirmed the earlier results - showing that regular screening extended the lives of heavy smokers.
A Task Force recommendation in favor of screening typically means insurers and Medicare will begin reimbursing for the procedure. As currently written, current and past heavy smokers age 55 - 79 are recommended for annual screening.
Being able to find lung cancer early when it is most treatable is a great advance for such a deadly cancer, which typically has a low rate of survival five years after diagnosis. Quitting smoking, however, remains the best way to lower the risk of lung cancer and improve survival in smokers. Compared to smokers who don't get screened, those who do have a 20 percent lower risk of dying from lung cancer over 6 years. Compared to smokers who don't quit, those who do have a similar benefit over 5 years, and the longer someone has not smoked, the greater the benefit (see figure).
The benefits of stopping smoking is an old story - not likely to grab many headlines any more - but it's one that should be trumpeted along with these new guidelines on lung cancer screening.