Squamous cell carcinoma of the lung.

Patients who undergo baseline lung cancer screening are less likely to adhere to screening recommendations compared with the screening rates of patients who participate in randomized clinical trials, according to a meta-analysis now published in JAMA Network Open.

Undergoing regular cancer screening has been shown to reduce the risk of cancer mortality. Data from the 2018 National Health Interview Survey found that approximately 70% of eligible women underwent breast cancer screening within the past two years, and approximately 80% of eligible women received cervical cancer screening; however, only 5.9% of eligible adults underwent lung cancer screening in 2015. Explaining why lung cancer has lower screening adherence statistics compared with other cancers, the investigators, led by first author Maria Lopez-Olivio, MD, MSc, PhD, Assistant Professor in the Department of Health Services Research at the University of Texas MD Anderson Cancer Center, write, "Low-dose computed tomography for lung cancer screening is a relatively nascent field with most intervention efforts still focusing on increasing uptake and acceptability among patients and practitioners rather than promoting the importance of annual adherence."

To determine the rate of screening adherence outside of clinical trials, the authors analyzed 15 prospective and retrospective cohort studies related to lung cancer screening adherence from MEDLINE, Embase, Scopus, CINAHL, and Web of Science and included 16,863 patients in studies published between January 1, 2011 and February 28, 2020. The primary end point was the rate of lung cancer screening adherence after baseline screening with secondary end points of patient characteristics and rate of diagnostic testing after screening.

The authors recorded a lung cancer screening adherence rate of 55% and found that current smokers were less likely to adhere to lung cancer screening compared with former smokers, with an odds ratio of 0.70. Additionally, white participants were more likely to adhere to lung cancer screening compared with patients of races other than white, with an odds ratio of 2.0. Participants between 65 and 73 years old were more likely to adhere to lung cancer screening than people 50 to 64 years old, with an odds ratio of 1.4. Furthermore, participants who completed four or more years of college demonstrated increased adherence compared with people who did not complete college, with an odds ratio of 1.5.

"In this study, rates of lung cancer screening adherence in the US published in the literature varied widely and were lower than seen in the controlled setting of clinical trials. Few studies reported adherence beyond one subsequent screening after baseline," conclude the authors. "Although there is concern that screening rates nationally are low, equally important is the need for interventions to improve adherence to screening for current smokers and smokers from minority populations to fully realize the benefits of early detection of lung cancer."