Missed by the guidelines: A meta-analysis of USPSTF lung cancer screening ineligibility among patients diagnosed with lung cancer.

Abstract

10573 Background: Lung cancer (LC) screening utilizes low-dose CT recommended by the US Preventive Services Task Force (USPSTF) based on age and smoking history. However, the proportion of patients who develop LC but are ineligible for screening at diagnosis remains unclear. We performed a meta-analysis to quantify the burden of LCs missed under USPSTF 2013 and 2021 criteria and identify key reasons for ineligibility. Methods: We systematically searched PubMed, Embase, and Scopus to identify studies reporting USPSTF screening eligibility among adults diagnosed with primary LC who ever smoked. Data were pooled using random-effects models. Primary outcomes included pooled proportions (PP) of LC cases ineligible for USPSTF screening using 2013 and 2021 criteria. Secondary analyses evaluated reasons for ineligibility, including age, smoking pack-years (yrs), and quit-yrs. Statistical significance is defined as p <0.05. Heterogeneity was assessed using the I² statistic. Results: Eight studies comprising 12,487 LC cases utilized the USPSTF 2013 criteria. The PP of screening-ineligible cases was 57.6% (95% CI, 48.94%-66.2%; I²=97.3%). Under USPSTF 2021 criteria, 11 studies including 20,313 cases were analyzed, yielding a pooled ineligible proportion of 40.9% (95% CI, 31.9%-50.5%; I²=98.8%). In reason-specific analyses, insufficient smoking exposure (pack-yrs) was the primary cause of ineligibility using both criteria, accounting for 68.2% (2013) and 59.3% (2021) of ineligible cases. Age-based exclusions declined from 34.7% under USPSTF 2013 to 31.8% under USPSTF 2021. Quit-year restrictions contributed to ineligibility under both criteria (25.8% in 2013; 49.6% in 2021), reflecting a greater proportional contribution among remaining ineligible cases under the 2021 criteria. Categories of ineligibility were not mutually exclusive. Conclusions: More than half of LCs were ineligible for screening under USPSTF 2013 criteria, and over 40% remain ineligible under current guidelines. Smoking pack-year thresholds remain the primary reason for ineligibility to screen and thereby miss a cancer diagnosis. These findings highlight limitations of current criteria and support the development of alternative risk-based screening strategies. Lung cancer screening ineligibility under USPSTF 2013 and 2021 criteria. Pooled Proportion (95% CI) I² (%) USPSTF 2013 Criteria Overall Ineligibility 57.6% (48.4-66.2) 97 Age-based exclusion (<55 or >80 yrs) 34.7% (28.2-41.8) 70 Insufficient pack-yrs (<30) 68.2% (54.6-79.2) 93 Quit-year exclusion (>15 yrs) 25.8% (10.8-49.8) 97 USPSTF 2021 Criteria Overall Ineligibility 40.9% (31.9-50.5) 98 Age-based exclusion (<50 or >80) 31.8% (18.4-49.0) 96 Insufficient pack-yrs (<20) 59.3% (45.6-71.6) 89 Quit-year exclusion (>15 yrs) 49.6% (37.1-62.0) 94