An umbrella review of systematic evidence on the Low Dose Computed Tomography (LDCT) for lung cancer screening

Despite lung cancer's high mortality rate, many countries still lack organized lung cancer screening programs. This review aims to evaluate the impact of low-dose computed tomography (LDCT) screening on lung cancer diagnosis, mortality, and overall clinical outcomes. Following the Joanna Briggs Institute methodology for umbrella reviews, a comprehensive search was conducted in PubMed, Embase, and the Cochrane Library for reviews published between January 2013 and December 2023. Eligible meta-analyses included studies comparing LDCT screening with chest X-ray (CXR) or no screening, reporting outcomes such as sensitivity, specificity, and lung cancer mortality. The methodological quality of the included reviews was assessed using AMSTAR-2. Out of 801 citations, 14 meta-analyses met the inclusion criteria. LDCT demonstrated high sensitivity (0.97, 95% CI: 0.94-0.98) and specificity (0.87, 95% CI: 0.82-0.91). It significantly increased early-stage lung cancer detection (RR: 1.31, 95% CI: 1.18-1.45) and reduced lung cancer mortality by 18% (RR: 0.82, 95% CI: 0.75-0.90). However, the reduction in all-cause mortality (RR: 0.91, 95% CI: 0.75-1.06) was not statistically significant. Overdiagnosis and false positives remain essential challenges. This umbrella review confirms that LDCT screening effectively reduces lung cancer mortality, particularly in high-risk populations.