Paraganglioma: Causes, Symptoms, Diagnosis and Treatment — Overview, Diagnosis & Treatment Options | MyMedicPlus

Paragangliomas are rare neuroendocrine tumors arising from extraadrenal chromaffin cells (paraganglia). They occur in the head, neck, thorax, and abdomen. Incidence is approximately 2-8 cases per million per year. Head and neck paragangliomas (glomus tumors) are usually non-functional.

Approximately 35-40% are hereditary due to mutations in SDH subunit genes (SDHB, SDHC, SDHD, SDHA), VHL, RET, NF1, and MAX. SDHB mutations carry the highest malignancy risk (30-50%). Germline genetic testing is essential for all patients regardless of family history.

Functional tumors secrete catecholamines causing paroxysmal or sustained hypertension, headache, sweating, and palpitations. Head and neck paragangliomas present with pulsatile tinnitus, cranial nerve palsies, or neck mass. Many abdominal paragangliomas are discovered incidentally on imaging.

Plasma metanephrines and 24-hour urine catecholamines for biochemical assessment. 68Ga-DOTATATE PET/CT is preferred for functional imaging and staging. 123I-MIBG scintigraphy for MIBG-avid tumors. CT/MRI for anatomical localization. Germline SDH panel testing is mandatory for all patients.

Surgical resection is primary treatment. Pre-operative alpha-blockade (phenoxybenzamine 10-14 days) is mandatory for functional tumors to prevent hypertensive crisis. 177Lu-DOTATATE PRRT or 131I-MIBG therapy for metastatic/unresectable disease. Cabozantinib or sunitinib for progressive metastatic paraganglioma.

Benign localized paragangliomas have excellent outcomes after surgical resection. Malignant paraganglioma (defined by metastases) with SDHB mutation: 5-year survival approximately 36-60%. Long-term surveillance (every 1-2 years lifelong) is essential due to late recurrence risk decades after initial treatment.