VMA
Also written as: VMA — Vanillylmandelic Acid
Urine metabolite measured as a biomarker for neuroblastoma diagnosis and monitoring.
Full Definition
Vanillylmandelic Acid (VMA) is a urinary metabolite of catecholamines that serves as an important diagnostic and surveillance biomarker for neuroblastoma and other neural crest tumors. Elevated VMA levels in 24-hour urine collections or spot urine samples help establish the diagnosis of neuroblastoma and monitor treatment response. VMA is typically measured alongside homovanillic acid (HVA) as part of standard neuroblastoma workup. Normal VMA levels during treatment may indicate good therapeutic response, while persistently elevated levels may suggest residual or progressive disease.
Usage
Usage note: Often reported with HVA; specify collection method (24-hour vs. spot urine) and reference ranges.
In Context
- "Preoperative VMA and HVA levels were markedly elevated at 15 times the upper limit of normal." — Laboratory results summary
- "Surveillance VMA levels remained within normal range at the 6-month follow-up visit." — Follow-up care documentation