2018 Volume 55 Issue 3 Pages 284-287
Urinary vanillylmandelic acid (VMA) and homovanillic acid (HVA) detection is useful as an adjunct to the diagnosis of neuroblastoma. Previously, the “VMA spot test” was the only method of detecting urinary VMA. However, the spot test tended to yield false-positive results. Instead of the spot test, high-performance liquid chromatography (HPLC) is widely used nowadays. We have known that neither VMA nor HVA levels are elevated in approximately 10% of neuroblastoma patients. However, even in one-half of cases of such tumors, catecholamines or related metabolites were more or less secreted. Some previous studies demonstrated that the VMA spot test could detect various catecholamines and their metabolites, which are not specific for VMA. We have successfully identified two cases of VMA-negative neuroblastoma in the early phase on the basis of the positive results of the VMA spot test. In patients with tumors detected by image inspection, the VMA spot test would be a powerful tool for identifying neuroblastoma, even if the patients are negative for VMA and HVA.
