Comparing the performance of visual estimation and standard uptake value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography for detecting malignancy in pancreatic tumors other than invasive ductal carcinoma FDG-PET/CTでの浸潤性膵管癌以外の膵腫瘍の悪性病変の検出能における視覚評価と標準摂取率での評価の比較検討

博士論文

Introduction The utility of FDG PET/CT for the detection and evaluation of invasive ductal carcinoma has been widely reported, but a few studies have assessed the utility of FDG PET/CT to detect malignancy in a variety of pancreatic lesions other than invasive ductal carcinoma. Purpose To compare the diagnostic performance of visual estimation with the semi-quantitative scores of FDG PET/CT for detecting malignancy in a variety of pancreatic lesions other than invasive ductal carcinoma. Material and Methods Images of pathologically proven pancreatic lesions from 32 patients were retrospectively evaluated : 14 benign lesions, 7 borderline (low malignant) lesions, and 11 malignant lesions. The average scores from visual estimation by the two observers were compared to two semi-quantiative analyses of FDG uptake in the lesions, namely the maximum standardized uptake value (SUVmax) and mean standardized uptake value (SUVmean). Results Visual analysis value, SUVmax and SUVmean were 0.33±0.21, 1.8±0.7 and 1.5±0.7 for the benign lesions, 0.70±0.28, 5.0±2.6 and 3.1±1.7 for the borderline lesions, and 0.73±0.18, 4.7±2.5 and 3.2±1.6 for the malignant lesions, respectively. Receiver operating characteristic analysis revealed the areas under the curves for detecting non-benign (malignant or borderline) lesions through visual analysis, SUVmax, and SUVmean were 0.914, 0.954, and 0.875, respectively. Conclusion For a variety of pancreatic lesions other than invasive ductal carcinoma, visual analysis and semi-quantitative analyses all showed strong diagnostic performance. However, semi-quantitative analysis with SUVmax proved to be the most effective method for detecting non-benign pancreatic lesions.