Study suggests possible LDCT screening benefit for 20- to 29-pack-year smokers

Should 20- to 29-pack-year smokers be screened for lung cancer via low-dose CT just like those with 30-plus pack-years?

Maybe, suggest the authors of a new study.

Definitely, says at least one subject expert.

In research published Oct. 19 in the Journal of the National Cancer Institute, the NCI’s Paul Pinsky, PhD, and Barnett S. Kramer, PhD, describe their analysis of data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, a randomly assigned screening trial of subjects age 55 to 74 years with chest radiographs used for lung cancer.

According to a news release from Oxford University Press, publisher of the JNCI, the researchers also considered data from the National Health Interview Survey (NHIS), which looked at the smoking history and race/ethnicity of subjects and the demographic profiles of various high-risk smoking history categories.

They found that the risk of lung cancer among 20- to 29-pack-year current smokers was similar to that of 30-plus pack-year former smokers who meet the current guidelines for LDCT set by the United States Preventive Services Task Force (USPSTF).

In addition, current 20- to 29-pack-year smokers were more likely to be female and to be racial/ethnic minorities than were those meeting the current USPSTF guidelines.

Despite this compelling wrinkle, the researchers feel their results should be handled with caution.

This group was not included in the sweeping National Lung Screening Trial, so “there is the untested assumption that the trial’s mortality benefit can be extrapolated to them,” write the authors.

Until LDCT screening performance in population settings is better understood, they add, “expansion of screening to additional populations may incur unanticipated harms.”

In an accompanying editorial, however, Francine L. Jacobson, MD, MPH, of Brigham and Women’s Hospital contends that the findings in the Pinsky-Kramer study “demonstrate sufficient risk of lung cancer in a population with 20 to 29 pack-years to consider screening.”

“As we eliminate arbitrary divisions instituted for managing clinical trials,” writes Jacobsen, “we can approach important questions about differences in risk.”