P1.03-033 Analysis of T0 Lung-RADS Scores in UI Health's Minority-Based Lung Cancer Screening Program and Comparison to the NLST

Abstract

Lung Cancer (LC) is the leading cause of cancer death in the U.S. The incidence and mortality rate differs depending on smoking status, race, ethnicity, gender, and socioeconomic status (SES). African Americans (AA) have significantly higher incidence/mortality rates of LC. The National Lung Screening Trial (NLST) which showed a 20% reduction in LC mortality with low-dose CT (LDCT) screening only included 4.5% AA’s. LDCT screening amongst high risk minority individuals has not been sufficiently investigated. The goals of this study are: (1) to compare UI Health’s Screened Population (UIHSP) to the NLST and determine if NLST results are generalizable to an urban minority population; (2) to determine trends in UIHSP Lung-RADS based on age, gender, race/ethnicity, smoking-history, and comorbidities. Patients were referred to LDCT based on U.S. Preventative Services Task Force guidelines. Summary statistics, such as means, standard deviations, and ranges for continuous variables, and frequencies for categorical variables are provided. Spearman correlation coefficients are estimated between continuous variables (i.e., age, smoking pack-years) and Lung-RADS scores are estimated. Chi-squared tests and Fisher’s Exact tests were performed to test the associations between categorical variables and Lung-RADS scores. All statistical tests are two-sided, controlling for a Type I error probability of 0.05. Compared to the NLST, UIHSP has a higher percentage of AA’s (65% vs. 4.5%), rate of Lung-RADS 3 and 4, (30% vs 13.7%). UIHSP had a LC rate 3x that of NLST on T0 scan (3% vs 1%). A diagnosis of emphysema on LDCT scans was significantly associated with higher Lung-RADS scores (p = 0.0415). Patients who were diagnosed with emphysema detected on LDCT report had significantly higher Lung-RADS scores. 5 LC diagnoses in the first 163 T0-scans (3%), 4 of 5 were AAs. Males were more likely to have Lung-RADS 3 and 4 than females (OR=2.1, p=0.0353). Smoking-pack years demonstrated a positive correlation with higher Lung-RADS score (p=0.067). UIHSP compared to NLST demonstrated higher incidence of Lung-RADS 3 and 4 scores and diagnosis of LC at T0 LDCT scans. In addition this study has found a significant association between emphysema and higher Lung-RADS scores among UIHSP. These results support the conclusion from previous studies that emphysema on LDCT is an independent risk factor for LC. Furthermore, the results show a statistically significant correlation between gender and Lung-RADS scores. These statistical associations make the case for the modification of USPSTF guidelines to fit the risk-profile of minority populations like UIHSP.