[(123)I]metaiodobenzylguanidine and [(111)In]octreotide uptake in begnign and malignant pheochromocytomas

J Clin Endocrinol Metab. 2001 Feb;86(2):685-93. doi: 10.1210/jcem.86.2.7238.


Selecting the appropriate approach for resection and follow-up of pheochromocytomas (PCCs) is highly dependent upon reliable localization and exclusion of multifocal, bilateral, or metastatic disease. Metaiodobenzylguanidine (MIBG) scintigraphy was developed for functional localization of catecholamine-secreting tissues. Somatostatin receptor imaging (SRI) has a high sensitivity for localizing head and neck paragangliomas, but studies of intraabdominal PCCs are rare. In this study we review our experience of [(123)I]MIBG and SRI, performed since 1983 and 1989, respectively, in the work-up of primary and recurrent PCCs. Scintigraphic results were correlated with catecholamine secretion, size and site, malignancy, associated tumor syndromes, and morphological features. [(123)I]MIBG scans were performed in a total of 75 patients, in 70 cases before resection of primary PCCs and in 5 cases because of recurrent disease. Ninety-one PCCs were resected. The overall detection rates were 83.3% and 89.8% for PCCs larger than 1.0 cm. Multifocal disease was detected in 4 patients with [(123)I]MIBG. [(123)I]MIBG uptake correlated with greater size of PCC (r = 0.33; P = 0.008) and greater concentration of plasma epinephrine (r = 0.32; P = 0.006). [(123)I]MIBG-negative PCCs (n = 14) had significantly (P = 0.01) smaller diameters than [(123I)]MIBG-positive tumors. Furthermore, [(123)I]MIBG uptake was significantly higher in unilateral (P = 0.02), benign (P = 0.02), sporadic (P = 0.02), intraadrenal (P = 0.02), and capsular invasive (P = 0.03) PCCs than in bilateral, malignant, MEN2A/2B-related, extraadrenal, and noninvasive PCCs, respectively. The detection rate of SRI was only 25% (8 of 32) for primary benign PCCs. In 14 patients metastases occurred, which were effectively visualized with [(123)I]MIBG in 8 of 14 cases. SRI was able to detect metastases in 7 of 8 cases, including 3 [(123)I]MIBG-negative metastatic cases. In addition, [(123)I]MIBG and SRI detected 2 recurrences. In conclusion, [(123)I]MIBG uptake is correlated with the size, epinephrine production, and site of PCCs. Its role in bilateral and MEN2A/2B-related PCCs seems limited. In cases of recurrent elevation of catecholamines, localization of metastases and/or recurrence should be attempted with [(123)I]MIBG scintigraphy. In suspicious metastatic PCCs, SRI might be considered to supplement [(123)I]MIBG scintigraphy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3-Iodobenzylguanidine / pharmacokinetics*
  • Adolescent
  • Adrenal Gland Neoplasms / diagnostic imaging*
  • Adrenal Gland Neoplasms / metabolism
  • Adrenal Gland Neoplasms / mortality
  • Adrenal Gland Neoplasms / pathology
  • Adrenal Gland Neoplasms / surgery
  • Adult
  • Aged
  • Disease-Free Survival
  • Humans
  • Indium Radioisotopes / pharmacokinetics*
  • Iodine Radioisotopes / pharmacokinetics*
  • Middle Aged
  • Multiple Endocrine Neoplasia Type 2a / diagnostic imaging
  • Multiple Endocrine Neoplasia Type 2b / diagnostic imaging
  • Neoplasm Metastasis
  • Octreotide / pharmacokinetics*
  • Pheochromocytoma / diagnostic imaging*
  • Pheochromocytoma / metabolism
  • Pheochromocytoma / mortality
  • Pheochromocytoma / pathology
  • Pheochromocytoma / surgery
  • Radionuclide Imaging
  • Radiopharmaceuticals / pharmacokinetics*
  • Receptors, Somatostatin / analysis
  • Recurrence
  • Retrospective Studies
  • Survival Rate
  • Tissue Distribution


  • Indium Radioisotopes
  • Iodine Radioisotopes
  • Radiopharmaceuticals
  • Receptors, Somatostatin
  • 3-Iodobenzylguanidine
  • Octreotide