FRI224 A Rare Case Of Recurrent Paraganglioma Presented With Liver Metastasis

Abstract Disclosure: E. Gupta: None. M. Al Mushref: None. Malignant Paragangliomas (PGLs) and Pheochromocytomas (PCC) are extremely rare. Approximately 10% of PCCs and 25% of PGLs are metastatic. Metastatic PGLs typically occur in patients with predisposing genetic mutations. We present a case of recurrent metastatic PGL in a young female with no known genetic predisposition to metastatic disease occurring after surgical resection. Our patient is a 28-year-old female with a history of PGL status post left adrenalectomy and nephrectomy two and a half years prior who presented to the ED for abdominal pain. She was first diagnosed after being admitted for hypertensive emergency. During time of diagnosis, plasma and urinary metanephrines were significantly elevated at 1.13 nmol/L and 907 ug/gCr respectively and plasma and urinary normetanephrines were elevated at 80.2 nmol/L and 52043 ug/gCr respectively. MRI showed a 16 cm left retroperitoneal mass and MIBG scan showed increased uptake in the mass however no evidence of metastatic disease was noted then. The patient had immigrated from Haiti. Her mother had passed away at age 20 of unknown cause and her father has no known history. Genetic testing was negative for hereditary gene mutations including multiple SDHDs, VHL, NF1, MEN1 and MAX. Surgical exploration showed a giant left retroperitoneal neoplasm involving the left kidney and left adrenal and both organs were resected. Pathology revealed PGL, focally extending to peripheral specimen margin and benign retroperitoneal lymph nodes and soft tissues. Post-resection meta- and normetanephrines levels were normal. Unfortunately, the patient was lost to follow up after surgery. On this admission, she endorsed right lower quadrant abdominal pain. Plasma normetanephrine was 1.72 nmol/L, metanephrine was normal, and chromogranin A level was elevated at 545 ng/mL. CT scan revealed multiple hepatic lesions and MIBG scan further showed new increased uptake suggesting metastasis. The patient was asymptomatic and blood pressure remained normal during her hospitalization. Due to concerns of recurrent PGL with metastasis, she established care with Oncology for initiation of treatment. PGL is an extremely rare neuroendocrine tumor and is closely related to PCC. Sympathetic PGLs cause catecholamine surge symptoms but low volume disease may remain asymptomatic. Genetic predisposition is common in malignant PGL particularly succinate dehydrogenase mutation subunit B. Patients should be closely followed up to screen for recurrence and genetic testing should also be done. In our patient’s case, despite surgical resection and negative genetic testing, she developed recurrence of the PGL with new metastasis emphasizing the importance of close surveillance in the case of PGL to monitor for recurrence. Presentation: Friday, June 16, 2023