This month, Medicare began covering annual CT scans for lung cancer screening for those at highest risk of the disease. It's the first time a screening option proven to save lives is available for the disease that causes 160,000 deaths in the U.S. each year. But while some support the new policy, others say the evidence on the benefits on CT scans is uncertain, and that patients should carefully consider whether or not to get the screening.
Medicare's decision is exactly what the American Lung Association had hoped for. The senior vice president of the association's Northeast branch, Ed Miller, says thousands of lives will be saved from earlier detection of what is the deadliest form of cancer.
"It actually has the worst survival rate of any cancer that we have," Miller says. "It's a serious problem. And part of the reason it's so deadly is we have not been able to pick it up early. People get diagnosed with lung cancer very late, and many times there is nothing that can be done."
The new policy covers annual CT scans for people aged 55 to 77 with a 30 pack-year smoking history, who either currently smoke or quit within the last 15 years. The decision was made based on the results of the National Lung Screening Trial, a multi-year study which found that CT scans reduced the risk of dying from lung cancer.
"That actually showed such good results they shut down the trial because it would have been unethical to continue it," Miller says.
But Dr. Paul Han, the director of the Center for Outcomes Research and Evaluation at Maine Medical Center, says the study found that the reduction in deaths as a measure of absolute risk was less than 1 percent. Still, Han says that will add up to thousands of lives saved nationwide.
"There was clearly a mortality benefit to screening," Han says. "On the other hand, because we haven't really studied this intervention in the real world and community settings, I think there is substantial uncertainty."
One real world uncertainty is the radiation levels of CT scans. Trisha Calvo, health editor at Consumer Reports, says CT scans in and of themselves can cause cancer, and there's no federal standard for maximum radiation levels.
"So the dosage of radiation you can get from the same test, even in the same facility, varies," Calvo says. "So your best bet is to avoid any unnecessary CT scans."
One CT scan may not present much risk, Calvo says, but the cumulative effect from multiple scans is a concern. Another issue with the screening that experts point out is the potential for false positives.
Dr. David Newman is the editor in chief of the website thennt.com, which stands for the "number needed to treat." In the case of CT scans for lung cancer screening, death was prevented in one of 217 people screened. "I'm not even sure it means proceed. It means take caution," Newman says.
Newman says while some people will reap the benefit of living longer from a CT scan screening, many more will be harmed through false positives and unnecessary surgeries. He says the overall benefit of the new policy is still an open question.
"We're in this position where we tend to take things up and run with them as soon as we find a single investigation that shows any hint of benefit, even despite years of randomized trials that didn't show a benefit," Newman says.
Some physicians also think it's important to consider the screening in the context of the country's high health care costs. Portland physician Dr. Steve Dobieski says if you take into account the number of CT scans needed to detect one lung cancer, it costs hundreds of thousands of dollars for each life saved.
"That's a fairly expensive proposition," Dobieski says, "and when you think about it, what that money could do for smoking cessation and how many lives it could impact if there was a more robust smoking cessation program, it makes you start to wonder whether this is the best place to spend the money for lung cancer screening."
For all of these uncertainties, Dr. Paul Han of Maine Medical Center says it's critical that each eligible patient decide for themselves whether screening makes sense. Medicare's new policy actually requires what's called a "shared decision making visit" before a patient can get the screening, so they can discuss with their physicians both the benefits and risks of CT scans for lung cancer screening.
