Diagnostic Value of 18F-FDG PET/MRI For Staging in Patients With Ovarian Cancer

Abstract Purpose To evaluate the diagnostic potential of PET/MRI with 18F-fluorodeoxyglucose (18F-FDG) in ovarian cancer. Materials and Methods Participants comprised 103 patients with suspected ovarian cancer underwent pretreatment 18F-FDG PET/MRI, contrast-enhanced CT (ceCT) and pelvic dynamic contrast-enhanced MRI (ceMRI). Diagnostic performance of 18F-FDG PET/MRI and ceMRI for assessing the characterization and the extent of the primary tumor (T stage) and 18F-FDG PET/MRI and ceCT for assessing nodal (N stage) and distant (M stage) metastases was evaluated by two experienced readers. Histopathological and follow-up imaging results were used as the gold standard. The McNemar test was employed for statistical analysis. Results Accuracy for the characterization of suspected ovarian cancer was significantly better for 18F-FDG PET/MRI (92.5%) than for ceMRI (80.6%; p < 0.05). Accuracy for T status was 96.4% and 92.9% for 18F-FDG PET/MRI and ceMRI/ceCT, respectively. Patient-based accuracies for N and M status were 100% and 100% for 18F-FDG PET/MRI and 85.2% and 30.8% for ceCT and M staging representing significant differences (p < 0.01). Lesion-based sensitivity, specificity and accuracy for N status were 78.6%, 95.7% and 93.9% for 18F-FDG PET/MRI and 42.9%, 96.6% and 90.8% for ceCT. Conclusions Use of 18F-FDG PET/MRI offers higher diagnostic value for the characterization and M staging than ceMRI and ceCT, and diagnostic value for T and N staging equivalent to ceMRI and ceCT, suggesting that 18F-FDG PET/MRI might represent a useful diagnostic alternative to conventional imaging modalities in ovarian cancer.