131I-MIBG radionuclide therapy is safe and cost-effective in the control of symptoms of the carcinoid syndrome

Background The standard treatment used to control the symptoms of carcinoid syndrome (CS) involves subcutaneous injections of the somatostatin analogue octreotide. This is expensive (US$8000–16 000 per year), and treatment may be for many years. The aim of this study was to evaluate the efficacy and cost-effectiveness of our experience over the last 5 years with 1-131-labelled metaiodobenzylguanidine (MIBG) radionuclide therapy in the palliation of patients with CS.Methods A consecutive series of 20 symptomatic patients (referred between 1994 and 1999) with CS were evaluated. Fifteen of them underwent123I-MIBG scanning. Of the 13 patients with significant tracer uptake in metastatic deposits compared to background, 12 underwent a course of therapeutic131I-MIBG (one patient refused). Symptoms, biochemical markers, CT scans, follow-up123I-MIBG scans, and the requirement for octreotide were used to assess outcome of treatment. Costs of131I-MIBG and octreotide treatments were compared. Results MIBG treatment was well tolerated in all with only transient side-effects. Ten patients showed a measurable clinical improvement. Seven had a complete clinical response. The mean duration of response was 15.4 months. Octreotide was not required or was reduced in eight patients. Treatment with131I-MIBG resulted in a saving of US$1000 per patient, with effective symptom control, when compared to octreotide.Conclusion 1-131 MIBG therapy is a safe and cost-effective therapeutic option to successfully control symptoms in patients with carcinoid syndrome.