Biochemical detection of phaeochromocytoma: why are we continuing to ignore the evidence?

Phaeochromocytomas are rare tumours that require consideration among large numbers of patients with hypertension. If not diagnosed, the excessive secretion of catecholamines by these tumours can cause considerable morbidity and mortality. With a wide clinical variability in presentation, diagnosis can be difficult and invariably requires the biochemical confirmation of excessive catecholamine production by the tumour. At the First International Symposium on Phaeochromocytoma in October 2005, a panel of experts recommended that initial biochemical testing for phaeochromocytoma should include measurements of plasma and urinary metadrenalines. The accumulated evidence clearly indicates that measurement of fractionated metadrenalines in urine or plasma provides superior diagnostic sensitivity over plasma or urine measurements of catecholamines and metabolites. The low prevalence of phaeochromocytoma and paraganglioma (PGL) emphasizes the need to use biochemical tests of the highest sensitivity. To achieve this, it is recommended that the initial biochemical testing for phaeochromocytoma and secreting PGL should always include the measurements of metadrenalines in plasma or urine or both.