Usefulness of ¹²³I-MIBG Scintigraphy in the Evaluation of Patients with Known or Suspected Primary or Metastatic Pheochromocytoma or Paraganglioma: Results from a Prospective Multicenter Trial

Abstract

Although 123I-MIBG has been in clinical use for the imaging of pheochromocytoma for many years, a large multicenter evaluation of this agent has never been performed. The present study was designed to provide a prospective confirmation of the performance of 123I-MIBG scintigraphy for the evaluation of patients with known or suspected primary or metastatic pheochromocytoma or paraganglioma. Methods A total of 81 patients with a prior history of primary or metastatic pheochromocytoma or paraganglioma and 69 with suspected pheochromocytoma or paraganglioma based on symptoms of catecholamine excess, CT or MRI findings, or elevated catecholamine or metanephrine levels underwent whole-body planar and selected SPECT 24 h after the administration of 123I-MIBG. Images were independently interpreted by 3 masked readers, with consensus requiring agreement of at least 2 readers. Final diagnoses were based on histopathology, correlative imaging, catecholamine or metanephrine measurements, and clinical follow-up. Results Among 140 patients with definitive diagnoses (91, disease present; 49, disease absent), 123I-MIBG planar scintigraphy had a sensitivity and specificity of 82%. For patients evaluated for suspected disease, sensitivity and specificity were 88% and 84%, respectively. For the subpopulations of adrenal (pheochromocytoma) and extraadrenal (paraganglioma) tumors, sensitivities were 88% and 67%, respectively. The addition of SPECT increased reader confidence but minimally affected sensitivity and specificity. Conclusion This prospective study demonstrated a sensitivity of 82%–88% and specificity of 82%–84% for 123I-MIBG imaging used in the diagnostic assessment of primary or metastatic pheochromocytoma or paraganglioma.

Diagnostic Performance of 68Ga-DOTATATE PET/CT, 18F-FDG PET/CT and 131I-MIBG Scintigraphy in Mapping Metastatic Pheochromocytoma and Paraganglioma

“…Even though 123/131 I-metaiodobenzylguanidine ( 123/131 I-MIBG) scintigraphy is an excellent functional imaging tool in adrenal PCC, it has demonstrated low sensitivity in extraadrenal PGL and metastatic PCC/PGL [11][12][13]. In recent years, 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography (PET) has been suggested as a preferred functional imaging tool in malignant PCC/PGL, particularly in SDH and von Hippel-Lindau (VHL) germline mutation tumours or when de-differentiated tumour is suspected [15][16][17].…”

Pheochromocytomas detected by biochemical screening in predisposed subjects are associated with lower prevalence of clinical and biochemical manifestations and smaller tumors than pheochromocytomas detected by signs and symptoms

“…The reported sensitivity and specificity of MIBG scanning in patients with (suspected) pheochromocytoma range from 80 to 100% (17)(18)(19)(20)(21)(22). MIBG uptake correlates with the production of catecholamines (18).…”

Norepinephrine Transporter as a Target for Imaging and Therapy

“…False-negative scans are more frequent in those with the SDHB mutation or von HippelLindau syndrome-associated PHEO (41), probably due to lower expression of NET. In a prospective study in 140 patients, 123 I-MIBG showed specificity of 82% and sensitivity of 88% for PHEO and 67% for PGL (42). Patients with multiple endocrine neoplasia syndrome may also be evaluated with 123 I-MIBG to detect concurrent lesions in adrenal and thyroid glands.…”