Comparisons between glucose analogue 2-deoxy-2-(18F)fluoro-D-glucose and 18F-sodium fluoride positron emission tomography/computed tomography in breast cancer patients with bone lesions

Figure 1 A 49-year-old breast cancer patient with bone relapse. A lytic lesion on the fifth lumbar vertebra was detected with computed tomography in absence of local pain (A). The lesion showed high uptake both at ¹⁸F-FDG PET/CT (B) and ¹⁸F-NaF PET/CT (C), thus confirming its malignant nature. No further ¹⁸F-FDG avid metastasis was highlighted (E). By contrast a focal area of high ¹⁸F-NaF uptake was evident in the anterior branch of the seventh rib on the left side (F). This area was indeed corresponding to a small sclerotic indeterminate lesion on the CT and was considered as a further site of disease (D). The patient started systemic therapy rather than a targeted radiotherapy on the fifth lumbar vertebra. ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose; ¹⁸F-NaF: ¹⁸F-sodium; PET/CT: Positron emission tomography/computed tomography.

Figure 2 Evidence of the complementary features of 2-deoxy-2-(¹⁸F)fluoro-D-glucose and ¹⁸F-sodium positron emission tomography/computed tomography in the pelvis of the same breast cancer patient. An ¹⁸F-NaF avid sclerotic lesion was detected in the right sacrum in absence of significant ¹⁸F-FDG uptake. By contrast high uptake of ¹⁸F-FDG was present in a small lytic lesion in the left iliac bone. Due to the absence of a significant local bone reaction, this small lesion did not show any uptake of ¹⁸F-NaF. Both lesions corresponded to metastatic sites of disease and disappeared after chemotherapy. ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose; ¹⁸F-NaF: ¹⁸F-sodium; PET/CT: Positron emission tomography/computed tomography.

Figure 3 This area is likely to correspond to a bone marrow-confined metastasis not yet characterized by bone remodeling and thus falsely negative in both multidetector computed tomography and ¹⁸F-sodium positron emission tomography/computed tomography. No structural lesions or area of ¹⁸F-NaF uptake are evident in the vertebral column of this breast cancer patient (A); by contrast an area of high focal ¹⁸F-FDG uptake was present in the sixth dorsal vertebra (B). ¹⁸F-NaF: ¹⁸F-sodium; ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose.