Prospective comparison of 99mTc-MDP scintigraphy, combined 18F-NaF and 18F-FDG PET/CT, and whole-body MRI in patients with breast and prostate cancer

Abstract

We prospectively evaluated the use of combined 18F-NaF/18FFDG PET/CT in patients with breast and prostate cancer and compared the results with those for 99mTc-MDP bone scintigraphy and whole-body MRI. Methods: Thirty patients (15 women with breast cancer and 15 men with prostate cancer) referred for standard-ofcare bone scintigraphy were prospectively enrolled in this study. 18F-NaF/18F-FDG PET/CT and whole-body MRI were performed after bone scintigraphy. The whole-body MRI protocol consisted of both unenhanced and contrast-enhanced sequences. Lesions detected with each test were tabulated, and the results were compared. Results: For extraskeletal lesions, 18F-NaF/18F-FDG PET/CT and whole-body MRI had no statistically significant differences in sensitivity (92.9% vs. 92.9%, P 5 1.00), positive predictive value (81.3% vs. 86.7%, P 5 0.68), or accuracy (76.5% vs. 82.4%, P 5 0.56). However, 18F-NaF/18F-FDG PET/CT showed significantly higher sensitivity and accuracy than whole-body MRI (96.2% vs. 81.4%, P, 0.001, 89.8% vs. 74.7%, P 5 0.01) and bone scintigraphy (96.2% vs. 64.6%, P, 0.001, 89.8% vs. 65.9%, P, 0.001) for the detection of skeletal lesions. Overall, 18F-NaF/18F-FDG PET/CT showed higher sensitivity and accuracy than whole-body MRI (95.7% vs. 83.3%, P, 0.002, 87.6% vs. 76.0%, P, 0.02) but not statistically significantly so when compared with a combination of whole-body MRI and bone scintigraphy (95.7% vs. 91.6%, P 5 0.17, 87.6% vs. 83.0%, P 5 0.53). 18F-NaF/18F-FDG PET/CT showed no significant difference from a combination of 18F-NaF/18F-FDG PET/CT and whole-body MRI. No statistically significant differences in positive predictive value were noted among the 3 examinations. Conclusion: 18F-NaF/18F-FDG PET/CT is superior to whole-body MRI and 99mTc-MDP scintigraphy for evaluation of skeletal disease extent. Further, 18F-NaF/18F-FDG PET/CT and whole-body MRI detected extraskeletal disease that may change the management of these patients. 18F-NaF/18F-FDG PET/CT provides diagnostic ability similar to that of a combination of whole-body MRI and bone scintigraphy in patients with breast and prostate cancer. Larger cohorts are needed to confirm these preliminary findings, ideally using the newly introduced simultaneous PET/MRI scanners.