Abstract
We prospectively evaluate and compare the diagnostic performance of 99mTc-HDP planar bone scintigraphy (pBS), 99mTc-HDP SPECT/CT, 18F-NaF PET/CT and 18F-NaF PET/MRI for the detection of bone metastases. Methods: 117 patients with histologically proven malignancy referred for clinical pBS were prospectively enrolled. pBS and whole-body SPECT/CT were performed followed by 18F-NaF PET/CT within 9 days. 18F-NaF PET/MRI was also performed in 46 patients. A “truth panel” including clinical follow-up served as standard of reference. Results: Bone metastases were confirmed in 16 patients and excluded in 101. When equivocal readings were excluded no statistically significant difference in sensitivity, specificity, PPV, NPV or overall accuracy were found when comparing the different imaging techniques. With a pessimistic analysis, interpreting equivocal scans as positive, 18F-NaF-PET showed a significant higher specificity and accuracy than pBS (93.1% vs 81.2%, P = 0.012 and 91.5% vs. 79.5%, P = 0.011). With an optimistic analysis, interpreting equivocal scans as negative, 18F-NaF-PET showed significant higher accuracy than SPECT/CT (94.9% vs. 88.0%, P = 0.039) but not compared to pBS. The number of equivocal scans were significantly higher for pBS than for SPECT/CT and PET/CT (18 vs 5 and 6 respectively, P = 0.004 resp. P = 0.01). Conclusion: 18F-NaF PET/CT and whole body SPECT/CT resulted in a significant reduction of equivocal readings compared to pBS which implies an improved diagnostic confidence. However, this large prospective study could not verify prior published results on 18F-NaF-PET/CT superior overall accuracy compared to neither pBS nor whole-body SPECT/CT. The subgroup analysis of 46 patients with 18F-NaF-PET/MRI failed to demonstrate significantly improved overall diagnostic accuracy.
- Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.