From the Guidelines
Strontium-89 is the preferred treatment for malignant pheochromocytoma with bone metastases, as it provides effective pain relief and slows tumor growth. This radiopharmaceutical is administered intravenously at a typical dose of 4 mCi (148 MBq) as a single injection, targeting areas of increased bone turnover where metastases are present, and delivering localized radiation to reduce pain and slow tumor growth 1. Patients typically experience pain relief within 1-3 weeks after administration, with effects lasting 2-6 months. Before treatment, patients should have adequate bone marrow function (platelets >60,000/μL and white blood cells >2,400/μL) and normal renal function. Common side effects include temporary increase in bone pain, mild myelosuppression, and decreased blood counts.
- Key considerations for treatment with Strontium-89 include:
- Patient selection: those with widespread bone metastases that cannot be effectively treated with external beam radiation
- Dosing: 4 mCi (148 MBq) as a single injection
- Monitoring: for bone marrow function and renal function before and after treatment
- Side effects: temporary increase in bone pain, mild myelosuppression, and decreased blood counts Neither cobalt-60 (which is used in external beam radiation therapy) nor phosphorous-32 (used primarily for polycythemia vera) are standard treatments for malignant pheochromocytoma, and Strontium-89 is particularly valuable for patients with widespread bone metastases that cannot be effectively treated with external beam radiation 1. The most recent and highest quality study supports the use of Strontium-89 for this indication, as it provides effective pain relief and slows tumor growth, improving patient quality of life 1.
From the Research
Treatment Options for Malignant Pheochromocytoma
- The treatment of malignant pheochromocytoma involves various approaches, including surgical debulking, pharmacological control of hormone-mediated symptoms, targeted methods such as external irradiation, and systemic antineoplastic therapy 2, 3.
- Among the options for treating malignant pheochromocytoma, radiopharmaceutical therapy using [131I]meta-iodobenzylguanidine (MIBG) has shown promise, with high-specific-activity 131I-MIBG recently approved by the U.S. Food and Drug Administration for metastatic or inoperable pheochromocytoma or paraganglioma 4, 5.
- Chemotherapy regimens, such as cyclophosphamide, vincristine, and dacarbazine, have also been used to treat malignant pheochromocytoma, with variable success rates 2, 3, 5.
Radiopharmaceutical Therapy
- Radiolabeled metaiodobenzylguanidine (MIBG) and somatostatin receptor imaging have been used as theranostic agents for malignant pheochromocytoma 4.
- 131I-MIBG therapy has a long history of use in treating neuroendocrine tumors, including malignant pheochromocytoma 4.
- Peptide receptor radionuclide therapy with 90Y- or 177Lu-DOTA conjugated somatostatin analogs has also shown evidence of efficacy in treating malignant pheochromocytoma 4.
Comparison of Treatment Options
- The choice of treatment for malignant pheochromocytoma depends on various factors, including tumor progression, clinical manifestations, molecular features, and social factors 5.
- High specific activity iodine-131 metaiodobenzylguanidine has been shown to exhibit clinical benefits in more than 90% of patients treated, but other therapies with novel mechanisms of action are needed to help all patients with this disease 5.
Relevant Agents
- Among Strontium, Cobalt-60, and Phosphorus, none of these are directly mentioned as a treatment option for malignant pheochromocytoma in the provided studies 2, 3, 6, 4, 5.
- However, [131I]meta-iodobenzylguanidine (MIBG) is used for treating malignant pheochromocytoma, which involves the use of radioactive iodine 2, 4, 5.