Spot test for vanillylmandelic acid and other guaiacols in urine of patients with neuroblastoma

A spot test for vanillylmandelic acid and other guaiacol derivatives in the urine of patients with neuroblastoma is presented. The test is based upon the reaction of these substances with 2,4-dinitrophenylhydrazine and sodium metaperiodate which, when alkalinized with sodium carbonate, form a bright blue color. Nine of 13 cases of clinically apparent neuroblastoma (69%) were detectable by this test. Urine from 255 control subjects on unrestricted diets produced only one false positive reaction. The test is simple to perform and utilizes random urine specimens.