Fewer adults follow lung cancer screening guidelines than previously reported
In a systematic review and meta-analysis, researchers found that the overall pooled lung cancer screening adherence rate among adults was 55%, “much lower” than rates reported in large randomized clinical trials.
“Monitoring adherence rates for [lung cancer screening] outside clinical trials is important in understanding how lung cancer screening is being implemented,” Maria A. Lopez-Olivo, MD, PhD, an assistant professor in the division of cancer prevention and population sciences at the University of Texas MD Anderson Cancer Center, and colleagues wrote in JAMA Network Open.
The researchers analyzed 15 studies that included 16,863 patients. The mean age of the patients ranged from 50 to 75 years, and the percentage of men ranged from 42% to 65%. The percentage of current smokers varied from 42% to 76%, and their mean pack-year — or the average of number of 20-cigarette packs smoked per day multiplied by the number of years smoked, according to a previously published Morbidity and Mortality Weekly Report — smoking history ranged from 32 pack-years to 53 pack-years.
Lopez-Olivo and colleagues wrote that the pooled lung cancer screening adherence rate across all follow-up periods (range, 12-36 months) was 55% (95% CI, 44-66). Screening adherence rates ranged from 12% (95% CI, 8-20) to 91% (95% CI, 88-93). The differences in the rates were likely due to varying eligibility criteria for screening that the studies used, according to researchers.
In addition, current smokers were less likely to adhere to screening guidelines than former smokers (OR = 0.7; 95% CI, 0.62-0.8). According to the researchers, there was a greater likelihood of guideline adherence among white patients vs. patients of other races (OR = 2; 95% CI, 1.6-2.6); patients aged 65 to 73 years of age compared with those aged 50 to 64 years (OR = 1.4; 95% CI, 1-1.9); and those who completed 4 or more years of college vs. those who had not completed college (OR = 1.5; 95% CI, 1.1-2.1).
The researchers noted that the U.S. Preventive Services Task Force, the American Cancer Society and American College of Radiology have only recently begun recommending low-dose CT lung cancer screening in certain patients, and efforts so far have focused on increasing uptake and acceptance among health care professionals and patients “rather than promoting the importance of annual adherence,” the researchers wrote.
Conversely, colon and breast cancer guidelines have been “available and recommended for many years, and a great deal of effort has gone into educating patients, working with practitioners and understanding factors that relate to screening behaviors,” Lopez-Olivo and colleagues said, which may explain why screening rates for colon and breast cancer (68.8% and 70%, respectively) are higher than the rate for lung cancer.
According to the researchers, extending the recommended interval between lung cancer screenings may “increase screening adherence, reduce false-positive test results and decrease screening costs.”
American Academy of Family Physicians. USPSTF recommends Lung cancer screening with low-dose CT. https://www.aafp.org/news/health-of-the-public/20200715uspstfdraftlung.html. Accessed November 19, 2020.