Gunel E. Probability of malignancy in solitary pulmonary nodules using fluorine-18-FDG

Nearly one-third of solitary pulmonary nodules are radiographically indeterminate for the presence of malignancy. Methods: FDG-PET imaging was used to differentiate benign and malignant solitary pulmonary nodules in 61 patients with radiographically indetermi nate nodules. After confirmation of the histological diagnosis, the probability for cancer was established for positive and negative PET scans and compared to the risk estimates calculated using other patient variables. Results: FDG-PET had a sensitivity, specificity and positive predictive value of 93%, 88 % and 92%, respectively, for detecting malignancy in indeterminate solitary pulmonary nod ules. The probability of malignancy with a positive PET scan is 83%, which increases with the patient's age (90 % in>60 yr) and the size of the nodule. A negative PET scan is associated with only a 4.7% risk of malignancy. FDG-PET also accurately characterized hilar/ mediastinal lymphadenopathy in 12 patients with associated lymp