The evidence behind lung cancer screening: a narrative review of randomized clinical trials

Objective: This chapter serves as a narrative review of the randomized controlled trial (RCT) evidence demonstrating a reduction in lung cancer mortality with low-dose computed tomography (LDCT) and the interaction of aspects that contribute to an effective screening program. Background: Lung cancer accounts for more deaths than breast, colon, and prostate cancer combined—cancers with mature screening programs, whereas lung cancer is typically advanced when detected. Methods: A review of the literature on PubMed was conducted using the keywords related to lung cancer screening. A narrative review was compiled of the eight RCTs evaluating the efficacy of LDCT for lung cancer screening as well as subsequent publications related to these articles and guidelines. Conclusions: Lung cancer screening by chest X-ray is not effective; however, two large, randomized control trials, National Lung Screening Trial (NLST) and Nederlands-Leuvens Longkanker Screenings Onderzoek (NELSON), have demonstrated a mortality benefit for LDCT in a defined high-risk population. United States eligibility criteria are healthy individuals age 50–80 years, with a ≥20-pack-year smoking history, either current smokers or having quit ≤15 years ago. LDCT is an effective tool for lung cancer screening. Implementation of screening is a complex interplay of many factors that influence the impact and efficiency. Furthermore, screening involves trade-offs that can be viewed from various perspectives.