A80-2-33 Comparison of the Temple Healthy Chest Initiative (thci) Cohort With the National Lung Screening Trial (nlst) and Nelson Lung Cancer Screening Populations

Rationale Landmark randomized trials established the mortality benefit of low-dose computed tomography (LDCT) screening for lung cancer but enrolled populations with limited demographic diversity. The National Lung Screening Trial (NLST) included approximately 4-5% Black participants, while the NELSON trial included fewer than 1% non-White participants and only 16% women. These enrollment patterns raise questions about generalizability to current U.S. screening populations, especially following the 2021 USPSTF expansion of eligibility criteria to include adults aged 50-80 years with ≥20 pack-years. The Temple Healthy Chest Initiative (THCI), an urban community-based cohort, provides an opportunity to examine whether real-world LDCT screening participants reflect the trial populations that defined evidence-based policy. Methods 315 participants attending lung cancer screening at Temple Health consented to an observational study. Electronic medical record data and pre bronchodilator spirometry were collected, and low dose CT imaging underwent quantitative analysis with AVIEW COPD, (CORELINE). We analyzed baseline characteristics for participants screened between 2023 and 2025 who met USPSTF eligibility. Descriptive statistics were compared with published data from NLST (Aberle DR et al., N Engl J Med 2011;365:395-409) and NELSON (de Koning HJ et al., N Engl J Med 2020;382:503-513). Continuous variables are reported as mean ± SD; categorical data as percentages. Results Among 315 THCI participants, mean age was 63.2 ± 6.6 years; 60% were female; and mean BMI was 31.2 ± 8.1 kg/m². The cohort included 74.9% Black, 10.2% White, and 14% Hispanic or Latino participants. Current smokers comprised 60.8%, and COPD was present in 47.5%. Among those with obstruction (n = 150, 47.5%), GOLD 1-4 distribution was 12%, 49%, 30%, and 9%, respectively. The mean CAC score was 357.8 ± 102 (subset, n = 180). In contrast, NLST enrolled 26% women and 4% Black participants, while NELSON enrolled 16% women and <1% racial minorities. Both trials reported lower BMI (26-27 kg/m²) and comorbidity rates. THCI therefore represents a substantially more diverse and comorbid screening population. Conclusions Compared with NLST and NELSON, the THCI cohort demonstrates markedly greater representation of women and racial minorities, higher BMI, and greater cardiopulmonary comorbidity. These differences highlight the need to evaluate LDCT screening performance and adherence across diverse populations. Future analyses should assess whether such demographic variation influences screening yield, false-positive rates, and treatment outcomes. References: Aberle DR et al. N Engl J Med 2011;365:395-409.de Koning HJ et al. N Engl J Med 2020;382:503-513.