RESULTS: From 2014 to 2016, 31 patients were enrolled, 16 and 25 of whom were tested for Xp and CDT respectively, and 10 of whom had both tests performed. To date, 4 patients have developed cancer, 7 have not, and 20 are being followed without nodule growth (median 7 months). Mean age was 63 ± 15 years, 14 patients were male, 19 were either current/past smokers, and 5 had a prior cancer ≥5 years ago. Nodule size was 1.3 ± 0.7 cm, 5 were spiculated and 11 were in the upper lobe. Average cancer risk for the cohort according to risk models was 23% comprising 2 low, 25 indeterminate, and 4 high-risk nodules. Assuming lesions not yet identified as cancer in follow up are benign, CDT had a sensitivity (Sn) of 0% but a specificity (Sp) of 95% and Xp had a Sn of 67% and Sp of 62%. Reported CDT risk (low) was discordant with high attributed clinical risk in 1 case and moderate attributed clinical risk in 21 cases. Reported Xp risk (low) was discordant with high attributed clinical risk in 1 case and moderate attributed clinical risk in 7 cases. All four cases of cancer (3 primary lung and 1 non-lung) were reported as low risk by CDT while Xp reported only the non-lung cancer as low-risk.