will that pulmonary nodule become cancerous a risk prediction model for incident lung cancer this prospective investigation derived a prediction model for identifying risk of incident lung cancer among patients with visible lung nodules identified on computed tomography ct among 2924 eligible patients referred for evaluation of a pulmonary nodule to the stony brook lung cancer evaluation center between january 1 2002 and december 31 2015 171 developed incident lung cancer during the observation period cox proportional hazard models were used to model time until disease onset the sample was randomly divided into discovery n 1469 and replication n 1455 samples in the replication sample concordance was computed to indicate predictive accuracy and risk scores were calculated using the linear predictions youden index was used to identify highrisk versus lowrisk patients and cumulative lung cancer incidence was examined for highrisk and lowrisk groups multivariable analyses identified a combination of clinical and radiologic predictors for incident lung cancer including lnage lnpackyears smoking a history of cancer chronic obstructive pulmonary disease and several radiologic markers including spiculation ground glass opacity and nodule size the final model reliably detected patients who developed lung cancer in the replication sample c 086 sensitivityspecificity 073081 cumulative incidence of lung cancer was elevated in highrisk versus lowrisk groups hr 1434 95 confidence interval ci 8172518 quantification of reliable risk scores has high clinical utility enabling physicians to better stratify treatment protocols to manage patient care the final model is among the first tools developed to predict incident lung cancer in patients presenting with a concerning pulmonary nodule