CHGA and pheochromocytoma: In symptomatic patients, the biochemical diagnosis of paragangliomas and pheochromocytomas begins with the detection of catecholamine metabolites (metanephrine and normetanephrine) in urine or serum plasma.3,4 Other markers include serum chromogranin A and methoxytyramine, which can be detected in metastatic disease.3 Although imaging plays a role in the diagnosis of paragangliomas, histopathology remains the gold standard for diagnosis.3,4