PROBABILITY OF MALIGNANCY IN SOLITARY PULMONARY NODULES USING FLUORINE-18-FDG AND PET

Nearly one-third of solitary pulmonary nodules are radiographically in determinate for the presence of malignancy, Methods: FDG-PET imaging w as used to differentiate benign and malignant solitary pulmonary nodul es in 61 patients with radiographically indeterminate nodules. After c onfirmation of the histological diagnosis, the probability for cancer was established for positive and negative PET scans and compared to th e risk estimates calculated using other patient variables, Results: FD G-PET had a sensitivity, specificity and positive predictive value of 93%, 88% and 92%, respectively, for detecting malignancy in indetermin ate solitary pulmonary nodules, The probability of malignancy with a p ositive PET scan is 83%, which increases with the patient's age (90% i n >60 yr) and the size of the nodule. A negative PET scan is associate d with only a 4.7% risk of malignancy, FDG-PET also accurately charact erized hilar/ mediastinal lymphadenopathy in 12 patients with associat ed lymph node lesions, Conclusion: FDG-PET imaging can be a useful non invasive test to determine the risk estimate or probability of cancer as well as preoperative staging in patients with radiographically inde terminate solitary pulmonary nodules.