Cardiac paraganglioma with sulfur subunit B gene mutation: a case report

BACKGROUND: Pheochromocytoma and paraganglioma is a rare disease with a prevalence of 0.2-0.6% in hypertensive patients from outpatient. CASE SUMMARY: A 21-year-old man complained of blood pressure elevation over one year and persistent hyperhidrosis near 5 years. In local hospital, a mass in the pericardial space with abundant blood flow was observed via echocardiography and confirmed under minimally invasive thoracotomy. With suspicion of malignant cardiac mass, the patient was recommended to transfer for further diagnosis and treatment. Combining evaluation for blood and urinary catecholamine levels, somatostatin receptor imaging, and iodine-131 metaiodobenzylguanidine scintigraphy, he was confirmed with the diagnosis of cardiac paraganglioma with blood supply from the right coronary artery identified via angiography. The cardiac tumour was then surgically resected and confirmed with a pathological diagnosis of paraganglioma. Subsequent genetic test suggested succinate dehydrogenase complex iron sulfur subunit B (SDHB) gene mutation. At 5-month follow-up, the patient was recovered with normal levels of blood catecholamines and catecholamine metabolites. DISCUSSION: Cardiac paraganglioma should be considered and evaluated in hypertensive patients with cardiac mass, even in non-typical population. Given a potential risk of developing malignancies, close follow-up is significant in patients with SDHB gene mutations.