Efficacy of using a standard activity of (131)I-MIBG therapy in patients with disseminated neuroendocrine tumours

Eur J Nucl Med Mol Imaging. 2010 May;37(5):904-12. doi: 10.1007/s00259-009-1326-3. Epub 2009 Dec 17.


Purpose: The aim of this analysis was to evaluate the response to standard activity of (131)I-meta-iodobenzylguanidine (MIBG) in patients with disseminated neuroendocrine tumours (NETs), comparing overall survival of patients with symptomatic response, tumour size (as assessed by CT) and relevant plasma tumour markers.

Methods: A retrospective review of patients who had undergone (131)I-MIBG treatment between March 2001 and December 2006 was carried out. The administered activity of (131)I-MIBG was 5.5 GBq (NETs) and 7 GBq (phaeochromocytoma). Three cycles of treatment were planned with an interval of 10-12 weeks. A pre-therapy scan with (123)I-MIBG was performed to ascertain appropriate biodistribution.

Results: Thirty-eight patients were identified. Only two patients developed significant bone marrow suppression. Symptomatic response: data were available in 37 of 38 patients: 15 patients had improved symptoms, 19 had no improvement in symptoms and 3 were asymptomatic. In those with a symptomatic response, the median overall survival was 58 months vs no response of 20.0 months (p = 0.001). CT response: in those with stable disease, the median overall survival was 58 months compared with progressive disease of 16.0 months. The difference between these groups was significant (p = 0.006). Hormonal response: this was available in only 20 of 38 patients. The median overall survival was the same for patients that had increased hormone levels and patients that had stable/decreased hormone levels (48 months).

Conclusion: Standard activity (131)I-MIBG is well tolerated. Symptomatic response to treatment is a significant predictor of overall survival. Whilst CT response also appears to predict survival, hormonal levels do not appear to correlate with survival.

MeSH terms

  • 3-Iodobenzylguanidine / adverse effects
  • 3-Iodobenzylguanidine / therapeutic use*
  • Biomarkers, Tumor / blood
  • Disease Progression
  • Female
  • Hormones / metabolism
  • Humans
  • Male
  • Middle Aged
  • Neuroendocrine Tumors / diagnostic imaging
  • Neuroendocrine Tumors / metabolism
  • Neuroendocrine Tumors / pathology
  • Neuroendocrine Tumors / radiotherapy*
  • Radiopharmaceuticals / adverse effects
  • Radiopharmaceuticals / therapeutic use*
  • Retrospective Studies
  • Survival Analysis
  • Tomography, X-Ray Computed
  • Tumor Burden


  • Biomarkers, Tumor
  • Hormones
  • Radiopharmaceuticals
  • 3-Iodobenzylguanidine