Abstract 4215: Patient and screening characteristics associated with positive lung cancer screening examinations

Introduction. The likelihood of having a positive low dose computed tomography (LDCT) lung cancer screening (LCS) examination that requires workup may vary according to patients’ characteristics and risk factors. The purpose of this study is to evaluate patient characteristics associated with positive LCS exams. Methods. We utilized data from 1684 LDCT exams conducted for LCS at five academic and community sites from 2015-2018. During the screening visit, patients were asked to complete a comprehensive questionnaire including socio-demographics, smoking history, occupational and environmental exposures, family history of lung cancer, and comorbid conditions. Information on the LCS examination, including the radiologists’ Lung Reporting and Data System (Lung-RADS) assessment, was obtained from the radiologist report. We dichotomized Lung-RADS into negative (Lung-RADS 1 (negative) or 2 (benign appearance or behavior)) and positive (Lung-RADS 3 (probably benign), 4A (suspicious), or 4B (suspicious)) based on the management recommendation of continuing with annual screening in 12 months or requiring follow-up before 12 months. We compared Lung-RADS results (positive versus negative) by patient characteristics using chi-square tests and examined predictors of positive LCS exams using multivariate logistic regression, reporting adjusted odds ratios (aORs) and 95% confidence intervals (95%CI). Results. Screened patients ranged in age from 50-78 years, with 46.7% less than 65 years and 53.3% ages 65 or older. Approximately 53.3% were male and 46.7% were female; 84.5% were White, 11.8% were African American, and 3.7% were other races. The majority (76.5%) of screened patients were overweight or obese. Two-thirds (68.5%) of patients had more than one LCS exam. Most (85.0%) LCS exams were negative while 15.0% were positive. There were no significant differences in Lung-RADS assessment by race, gender, education, or body mass index. Lung-RADS were significantly more likely to be positive in those ages 65 and older versus those ages less than 65 (aOR=1.47, 95%CI: 1.03-2.10) and in baseline versus subsequent screening exams (aOR=0.43, 95%CI: 0.30-0.62). Conclusion. Predictors of having a positive LCS exam requiring work-up before the next recommended annual screening test include being aged 65 and older and having a baseline LCS examination. Citation Format: Louise M. Henderson, Samantha Sites, Tina Tailor, Sara C. Bearden, Roger Huamani, Allison Throneburg, Max Nagle,