High-Specific-Activity 131I-MIBG for the Treatment of Advanced Pheochromocytoma and Paraganglioma
Ruaa Al-Ward, Vania Balderrama Brondani, Sahar Sawani, Cheryl L. Potter, Guofan Xu, Steven G. Waguespack, Jeena Varghese, Mouhammed Amir Habra, Yang Lu, Camilo Jimenez- Radiology, Nuclear Medicine and imaging
- General Medicine
Background
Metastatic pheochromocytomas and paragangliomas (MPPGLs) are rare tumors with limited treatment options. High-specific-activity 131I-MIBG (HSA-131I-MIBG) is the only US Food and Drug Administration–approved therapy for MPPGL. We studied the efficacy and safety of HSA-131I-MIBG in routine clinical practice.
Patients and Methods
The primary endpoints were objective response rate (ORR) and disease control rate (DCR). Secondary endpoints were duration of response, blood pressure control, safety, overall and progression-free survival rates, MIBG uptake, and correlations with genetic background.
Results
The study included 25 patients. Twenty-four patients had distant metastases, 17 (68%) had hormonally active tumors, and 13 (52%) had previously received antineoplastic treatment. In 24 evaluable patients, the ORR was 38%, including 2 patients with complete response, and the DCR was 83%; median time to response was 12.5 months (95% confidence interval, 4.6–25.1). Twelve patients had sporadic disease, among whom the ORR was 25% and DCR was 83%. Twelve patients had hereditary disease (
The most common adverse events were grades 1–2 nausea/vomiting and transient bone marrow suppression. One patient developed premature ovarian failure. Reversible grades 3–4 myelosuppression were seen in 7 patients (28%). One patient had fatal pneumonitis.
Conclusions
HSA-131I-MIBG is associated with a high DCR in patients with MPPGL, regardless of underlying genetic mutation.