SAT-LB080 Peptide Receptor Radionuclide Therapy in Metastatic Pheochromocytoma and Paraganglioma: The Putrajaya Experience

BACKGROUND: Most metastatic pheochromocytoma (PCC) and paraganglioma (PGL) express somatostatin receptors (SSTR) similar to neuroendocrine tumors, which may benefit from peptide radionuclide receptor therapy (PRRT), a molecular targeted therapy to SSTR avid tumors. We describe 5 cases of progressive metastatic PCC/PGL who had PRRT from year 2015 to 2018. RESULTS: The patients were aged 18-51 years at diagnosis of PCC/PGL, with mean duration of disease to PRRT of 9.6 (4 - 19) years. Four patients with functional disease were on alpha-blockade prior to PRRT. All patients had surgery as first line therapy, with 3 had repeated surgeries prior to PRRT. One patient had trans-arterial chemo-embolization and one patient had alcohol ablation therapy prior PRRT. All patients underwent induction treatment of PRRT, consisting 4 cycles of Lu-177 DOTATATE given at 8-16 weeks apart, with dose ranged 68.8 - 207mCi (2.5 - 7.66 GBq). Two patients with functioning PCC/PGL experienced paroxysm during PRRT, requiring adjustment of infusion rate and anti-hypertensives. Three patients had partial response and the other 2 had mixed response at interim imaging assessment. The subsequent imaging post PRRT showed stable disease. One patient had transient worsening of disease clinically and biochemically at the treatment interim which improved with subsequent cycles of therapy. All patients with functioning disease showed improvement in symptoms and catecholamine levels upon completion of PRRT, of which, 2 of them had their antihypertensive agents stopped. CONCLUSION: PRRT helps in disease control in particularly the symptoms, blood pressure and biochemical parameters in patients with SSTR avid metastatic PCC/PGL. Further review required for long term outcome of PRRT. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.