Fig. 1
A 54-year-old patient with metastatic renal cell carcinoma and prior stereotactic radiosurgery. Follow-up MRI demonstrated progressively enhancing brain lesions suspicious for recurrent disease. Top panel demonstrates that a right thalamic lesion (green arrow) had low fluciclovine uptake (SUVmax of 1.0) as seen on transaxial PET (a), corresponding T1 + contrast (b), focal FLAIR hyperintensity (c), and fused FLAIR and PET (d). This lesion did not increase in size on follow-up MRI and was considered consistent with radiation necrosis. A right cerebellar lesion (blue arrow) in the same patient had high fluciclovine uptake (SUVmax of 5.3) on transaxial PET (e) and corresponding T1 + contrast (f) FLAIR hyperintensity (g) and fused FLAIR and PET (h). The right cerebellar lesion was found to be recurrent metastatic disease upon resection