Urinary pteridines on patients suffering from cancer. A comment on the method and results of Rao and associates and of Trehan and associates.

A diagnostic test for detecting malignancies has been reported by Rao and associates. This test has been extended by Trehan and associates as an index of disease status in acute myeloblastic leukemic patients on antileukemic drugs. The authors were able to demonstrate that by using the described assay various pteridines are measured and not exclusively 6-hydroxymethylpterin as reported by the above-mentioned authors. Furthermore, the urinary component which correlates to the status of malignant disease has to be interpreted as being neopterin. This conclusion can be drawn from previous studies conducted by the authors' laboratory.