ABSTRACT
Retroperitoneal paragangliomas are uncommon neuroendocrine tumors which are derived from extra-adrenal paraganglioma with various clinical signs and symptoms. Although most extra-adrenal paragangliomas are histologically benign, some tumors can synthesize and secrete excess catecholamine from the tumor. Excessive production of catecholamine causes numerous cardiovascular manifestations such as severe hypertension, cardiomyopathy, cardiac arrhythmias, and even multiorgan failure. It can lead to high risks of morbidity and mortality, especially in patients who are unrecognized or not adequately prepared. We present a female patient who was preoperatively undiagnosed of secreting retroperitoneal paraganglioma that caused cardiac tachyarrhythmia and severe intraopertive hypertension not controlled by usual antihypertensive agents. A secreting extra-adrenal paraganglioma should be included in differential diagnosis for patient who have incidentaloma and show wide range of hypertension with hemodynamic instability that is not well controlled by common antihypertensive drugs.