LAUSR

PurposeThe purpose of this study is to assess the heterogeneity of tumor enhancement using fractal analysis on contrast-enhanced computed tomography (CE-CT) for predicting malignant potential of gastrointestinal stromal tumor (GIST).MethodsWe retrospectively identified 64 patients (36 M/28 W; median age: 65) with GISTs who received CE-CT and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) followed by curative surgery. Fractal analysis was applied to CE-CT image, and fractal dimension (FD) was measured. Diagnostic value of FD for malignant potential of GIST was compared with that of FDG-PET using the risk classification and Ki67 index.Results14 patients were categorized as the high risk, and 50 patients were as the very low, low or intermediate risk. FD of high-risk group was significantly higher than that of the other-risk group (p < 0.05). The areas under the ROC curves of FD and SUVmax for prediction of high-risk group were 0.82 and 0.93 (accuracy: 84.4% and 98.5%). FD showed a significant positive correlation with Ki67 index (p = 0.01).ConclusionDiagnostic value of CT fractal analysis for prediction of high-risk GIST is comparable with FDG-PET. In terms of cost and availability, fractal analysis has a potential to be an optimal preoperative biomarker.