Newer Chemical Diagnostic Tests

Undoubtedly, one of the most striking advances in the diagnosis and treatment of tumors in children in the last ten years has been the association of the excretion of catecholamines and metabolites in urine with neuroblastoma. These investigations were initiated by the report of increased excretion of pressor amines by Mason and his co-workers¹² in 1957 followed by numerous reports in which a whole spectrum of metabolites was investigated (for summary, see Bell¹³). The materials of major interest in the diagnosis of neuroblastoma are illustrated in Fig 1, although in normal adrenal tissue, the pathway is extended beyond norepinephrine to epinephrine. In the majority of cases of neuroblastoma, the pathways noradrenaline to VMA and dopamine to HVA appear to be the most important, but in a minority, the transamination pathway from 4-hydroxy-3-methoxy-phenylalanine (HMPA) to 4-hydroxy-3-methoxyphenyl lactic acid (HMPLA) and HVA is of greater significance.¹⁴

Problems of Differential