Utility of the PET/CT in the characterization of the solitary pulmonary nodule

Abstract

Background – The cancer of lung/trachea and bronchi is the leading cause of death from cancer in the European Union. Dual time in Positron Emission Tomography/Computed Tomography (PET/CT) technique has been referred in some articles as a great value in pulmonary cancer diagnosis. The aim of this study is to evaluate the PET/CT diagnostic accuracy with dual time in characterization of solitary pulmonary nodule (NSP), analyzing the nodule histology and size. Methodology – There were 115 NSP analyzed, a total of 110 patients, where 65 were malignant. Two images were acquired, one with an average time of 52 minutes and another one with 125 minutes after 18F-2-fluoro-2-deoxy-Dglucose (18F-FDG) injection. The standard uptake value (SUVmax) and percentage of changes in SUVmax (%variation) were obtained to analyse those images. Results – The %variation shows higher values of diagnostic accuracy than when analyzing SUVmax separately. However there are significant differences in histology and SUVmax, registering also an increase of SUVmax2 in malignant pathologies comparatively with SUVmax1. Conclusion – Dual time technique showed to be more efficient in NSP characterization than when analyzing only one image.

Keywords

• duplo tempo, nódulo solitário pulmonar, SUVmax, %variação