[Catecholamines and their derivatives in the study of pheochromocytoma].

The biochemical diagnosis of pheochromocytoma is essentially based on the plasma and urinary levels of catecholamines and their derivatives, the metanephrines and vanyl-mandelic acid. The advantages and disadvantages of these investigations are reviewed, especially as regards the specificity and sensitivity of each test. The measurement of urinary metanephrine is the best test as its excretion is relatively higher, and it is rarely normal. The measurement of plasma catecholamines is more difficult but gives satisfactory results, but experience so far is limited.