18F-FDOPA PET Compared With 123I-Metaiodobenzylguanidine Scintigraphy and 18F-FDG PET in Secreting Sporadic Pheochromocytoma.

We report the case of a 23-year-old man presenting a right hypersecreting pheochromocytoma, falsely negative on F-FDG PET/CT and on I-metaiodobenzylguanidine (I-MIBG) scintigraphy but strongly positive on F-FDOPA PET/CT. Functional imaging has a key role in diagnosis and prognosis of pheochromocytomas, but choosing the most relevant modality remains difficult. Despite its high specificity, I-MIBG has a limited sensitivity. F-FDG can be used, but it is an unspecific tracer, and F-FDG uptake in brown adipose tissue can hinder the analysis. However, F-FDOPA shows very high sensitivity and specificity in pheochromocytomas with fewer drug interferences than I-MIBG.