Urinary homovanillic (HVA) and vanillylmandelic (VMA) acids were analyzed on 200 random urine samples from patients with neuroblastoma and controls, after the samples had been dried onto absorbent filter paper. The acids were determined quantitatively by gas chromatography (GC) and qualitatively by thin layer chromatography (TLC). The results were analyzed for correlation between liquid urine samples and urine dried on filter paper and between TLC and GC methods. A high overall correlation for HVA and VMA (99%) was found between liquid and dried filter samples analyzed by GC. The correlations were more significant for samples with elevated levels of these acids than for those with normal levels. Normalization of the results to the urinary creatinine concentration (UCr) is indicated due to variations in urine concentration. Results from TLC analysis showed a false positive rate of 3.5% and a false negative rate of 0.5% compared to GC analysis. This work suggests that a combination of a sensitive TLC method with a rapid quantitative GC method would be suitable for mass neuroblastoma screening in infants.
Bibliographical noteFunding Information:
This work was supported in part by N1H Grant No. T32-CA0944S and the Children's Cancer Research Fund of the University of Minnesota. We thank Dr. Charles Scriver for initiating the collaboration on neuroblastoma screening between the centers in Canada and the United States. We also thank Mr. Robert Gigubre and Mr. Michael Rosenberg for their technical assistance and Ms. Cyndi Launer for aiding with the statistical analysis.
- acids, urinary
- chromatography, gas
- chromatography, thin layer
- homovanillic acid
- neuroblastoma, screening
- vanillylmandelic acid