Management of an incidentally discovered pulmonary nodule

The incidental finding of a pulmonary nodule on computed tomography (CT) is becoming an increasingly frequent event. The discovery of such a nodule should evoke the possibility of a small bronchogenic carcinoma, for which excision is indicated without delay. However, invasive diagnostic procedures should be avoided in the case of a benign lesion. The objectives of this review article are: (1) to analyze the CT criteria defining benign nodules, nodules of high suspicion of malignancy and indeterminate nodules, (2) to analyze the diagnostic performances and limitations of complementary investigations requested to characterize indeterminate lung nodules, (3) to review the criteria permitting to assess the probability of malignancy of indeterminate nodules and (4) to report on the new guidelines provided by the Fleischner Society for the management of small indeterminate pulmonary nodules, according to their prior probability of malignancy.