PULMONARY ABNORMALITIES AND PET DATA-ANALYSIS - A RETROSPECTIVE STUDY

PURPOSE: To assess methods of standard uptake ratio (SUR) calculation with 2-deoxy-2-[fluorine-18]fluoro-D-glucose (FDG) positron emission t omography (PET) in indeterminate focal pulmonary abnormalities. MATERI ALS AND METHODS: One hundred ninety-seven adult patients with indeterm inate pulmonary abnormalities had complete FDG PET data, consistent me thods of data acquisition, and definitive diagnosis with tissue biopsy or negative 2-year follow-up findings. PET studies were evaluated by using SURs calculated with the average or maximum region-of-interest p ixel value in the numerator and with weight, lean body mass, or body s urface area in the denominator. RESULTS: One hundred twenty malignant lesions and 77 benign processes were identified. Receiver operating ch aracteristic (ROC) curve areas were statistically significantly larger with the average rather than the maximum pixel value in the calculati on of the SUR for any of the three denominators (P less than or equal to .05). SURs calculated with weight versus lean body mass versus body surface area in the denominator showed no statistically significant d ifference in ROC curve areas. CONCLUSION: SURs determined by using ave rage pixel values provide statistically significant improvement in ROC curve areas over those determined by using maximum pixel values. Weig ht, lean body mass, and body surface area in the denominator of the SU R calculation provide equivalent ROC curve areas and are therefore equ ivalent in accuracy in this population.