Catecholamine metabolism in neuroblastoma.

Previous studies indicating the importance of catecholamine metabolism in neuroblastoma were briefly reviewed. Metabolic pathways were presented showing how the major urinary metabolites 3-methoxy-4-hydroxymandelic acid (VMA) and 3-methoxy-4-hydroxy-phenylacetic acid (HVA) are formed from norepinephrine and from dopamine plus 3,4-dihydroxyphenylalanine (DOPA), respectively. For 289 neuroblastoma patients at the time of diagnosis, the urinary excretion of VMA was significantly elevated in 75%, and HVA was elevated in 80%.

Studies on tyrosine hydroxylase in neuroblastoma in relation to urinary levels of catecholamine metabolites.

Tyrosine hydroxylase (TH) activity has been determined in 22 neuroblastoma tumors from 15 patients, in 1 pheochromocytoma, 20 adrenal glands, 10 other tumors and organs, and 4 specimens of sera. The enzyme activity was found only in the neural crest tumors and adrenal glands, but the levels were too low to be detected in the other tumors and in normal liver and kidney tissues. The average specific activity (mean +/- SE) of TH in 23 neural crest tumors was 0.