High rates of incidental findings, limited risk-reward outcomes and unnecessary emotional stress suggest that lung cancer screening efforts need to be refined. And, according to authors of a JAMA article, the risk and benefits should be clearly communicated to improve screening in high-risk patients.
California researchers argued this point in an article published online Jan. 22 in JAMA Internal Medicine.
Currently, the U.S. Preventative Services Task Force recommends screening for lung cancer with annual low-dose CT for high-risk populations ages 55 to 80. With guidelines stipulating screening for those having greater than 30 pack-year cumulative smoking history and having quit within the past 15 years.
However, corresponding author Rita F. Redberg, MD, and Michael Incze, MD, both with the University of California, San Francisco, claim those guidelines are based primarily on one trial, while many others failed to show a mortality benefit of lung cancer screening (LCS).
Authors point to a well-rounded study done by the Veteran’s Health Administration as proof of their claims that that real-world application use in low-risk patients coupled with high rates of incidental findings and false-positives results in a higher harm to benefit ratio for LCS.
The study was conducted in a high-risk population that demonstrated 56 percent of those screened had nodules requiring follow-up with repeated imaging and/or invasive procedures and 40 percent had incidental findings, such as emphysema and coronary artery calcification. Also, researchers found a relatively low cancer detection rate of 1.5 percent.
Cost-effectiveness of LCS and concerns over radiation exposure were other examples cited by the authors to suggest a need for more targeted inclusion criteria to lower the total number of patients screened and false-positivity rate.
Risk stratifying tools were argued as effective in refining guidelines. One example—the Bach risk tool—was presented as evidence for the need. The model uses sex, age, smoking duration, duration of abstinence from smoking and number of cigarettes smoked per day as inputs.
The high rates of false-positive in the lowest risk categories (2,221 false-positives per lung cancer death averted) coupled with “extremely” low rates of lung cancer incidence in the lowest-risk groups confirms the need for a change, according to authors.
However, there is still much to be worked out.
“Clearly more work is needed to minimize the harms of radiation exposure, invasive procedures, and emotional stress under current guide- lines, while preserving benefit for those whose lives could be saved by the early detection of lung cancer,” Redberg et al. wrote. “If and how we will get there has yet to be determined, but one thing is clear: the future of LCS depends on our ability to reexamine and refine our approach to patient selection and clearly communicate risks and benefits of screening.”