Abstract A132: Missed Opportunities? Regional availability of Low Dose CT lung cancer screening facility locations in the year prior to diagnoses: A descriptive comparison of American Indian and Non-Hispanic White lung cancer patients in North Carolina
Authors: Jackson Bradford E. , Emerson Marc , Carrizosa Daniel , Baggett Chris , Spees Lisa , Begay Joel , Salas Ana , Raveendran Yadurshirni , Akinyemiju Tomi , Denlinger-Apte Rachel , Wheeler Stephanie , Bell Ronny 
Published: September 2024

Abstract
INTRODUCTION American Indians (AI) have much higher incidence rates of lung cancer (LC) compared with non-Hispanic Whites (NHW) in the US. While low-dose computed tomography (LDCT) screening facilitates early detection of lung cancer, it is unknown how available LDCT screenings are to racially and geographically diverse populations in North Carolina (NC). To address this gap in knowledge, we conducted a descriptive study to characterize incident LC cases among AIs and NHWs, the distance from their location at diagnosis to the nearest LDCT screening facility and explored whether distance was associated with late-stage LC diagnoses. Methods Data were obtained from the Cancer Information and Population Health Resource (CIPHR), which comprise data from NC Central Cancer Registry (CCR) as well as public and private health insurance claims for the state. We identified ZIP codes and dates of rendered service for facilities providing LDCT by searching through claims from 2015-20. In addition, we identified incident LC cases among AIs and NHWs aged ≥18 years, from 2015-19. We assembled lists of LDCT facilities that existed in the year prior to each incident LC case. We calculated the minimum centroid to centroid distance to all facilities. Clinical attributes included age at diagnosis, sex, histology, stage at diagnosis, and rurality as measured by Rural Urban Commuting Area. Risk ratios were calculated for late-stage LC diagnoses across a range of thresholds for patient’s distance to nearest LDCT screening facility for AIs and NHWs. Results We identified 388 AI and 26,867 NHW incident LC cases in NC between 2015-20. Compared to NHWs, the median age at diagnosis for AIs was 5 years younger (AI: 65 vs. NHW: 69); more frequently male (AI: 54% vs NHW: 51%); and almost twice as likely to reside in rural areas (AI: 52% vs. NHW: 28%). There were no differences in late-stage LC diagnoses (AI: 54% vs. NHW: 52%). For distance (in miles) to the nearest LDCT screening facility, the median [Interquartile range] was twice as high for AIs (9.9 miles [0.8, 16.30]) compared to NHWs (5.3 miles [0, 12.1]). Among NHWs, there were statistically significant associations between distance and late-stage LC diagnosis at the shortest distance threshold of 5 miles (RR=1.04; 95%CL: 1.02, 1.07) through the threshold of 30 miles (RR=1.10 95%CL: 1.05, 1.15). There was no association across any distance threshold among AI lung cancer patients. Conclusions The large difference in accessibility of LDCT screening was not strongly associated with metastatic lung cancer diagnoses, possibly because so many patients were diagnosed late, reflecting poor early detection across all populations. We found that 80% of AIs with LC lived more than 10 miles away from LDCT screening facilities. This geographic distance may increase difficulty accessing cancer care geographically, and contribute to suboptimal LC screening rates. If efforts are to be made to increase early detection and improve survival, accessibility needs to be addressed on different dimensions.
Citation Format: Bradford E. Jackson, Marc Emerson, Daniel Carrizosa, Chris Baggett, Lisa Spees, Joel Begay, Ana Salas, Yadurshirni Raveendran, Tomi Akinyemiju, Rachel Denlinger-Apte, Stephanie Wheeler, Ronny Bell. Missed Opportunities? Regional availability of Low Dose CT lung cancer screening facility locations in the year prior to diagnoses: A descriptive comparison of American Indian and Non-Hispanic White lung cancer patients in North Carolina [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A132.