We compared functional imaging modalities including PET with 6-(18)F-fluorodopamine ((18)F-DA) with (123)I-metaiodobenzylguanidine ((123)I-MIBG) and somatostatin receptor scintigraphy (SRS) with (111)In-pentetreotide in nonmetastatic and metastatic pheochromocytoma (PHEO).
Methods: We studied 25 men and 28 women (mean age +/- SD, 44.2 +/- 14.2 y) with biochemically proven nonmetastatic (n = 17) or metastatic (n = 36) PHEO. Evaluation included anatomic imaging with CT or MRI and functional imaging that included at least 2 nuclear medicine modalities: (18)F-DA PET, (123)I-MIBG scintigraphy, or SRS. Sensitivity of functional imaging versus anatomic imaging was assessed on a per-patient and a per-region basis.
Results: For this available cohort, on a per-patient basis overall sensitivity (combined for nonmetastatic and metastatic PHEO) was 90.2% for (18)F-DA PET, 76.0% for (123)I-MIBG scintigraphy, and 22.0% for SRS. On a per-region basis, overall sensitivity was 75.4% for (18)F-DA PET, 63.4% for (123)I-MIBG scintigraphy, and 64.0% for SRS.
Conclusion: If available, (18)F-DA PET should be used in the evaluation of PHEO, because it is more sensitive than (123)I-MIBG scintigraphy or SRS. If (18)F-DA PET is not available, (123)I-MIBG scintigraphy (for nonmetastatic or adrenal PHEO) and SRS (for metastatic PHEO) should be the first alternative imaging methods to be used.