Investigation of urinary 6-hydroxymethylpterin concentrations in patients with malignant tumors in the oral and maxillofacial region

In 1981, Rao et al. reported that urinary 6-hydroxymethylpterin (6-HMP), which is increased in patients with malignant tumors is useful as a tumor marker. In this study, we developed a new technique to measure urinary 6-HMP concentrations by high performance liquid chromatography (HPLC). Basic studies of 6-HMP were carried out in 32 patients with malignant tumors of the oral and maxillofacial region and 76 healthy volunteers to evaluate the usefulness of this marker. The results were as follows:1) The coefficient of variance (%) for reproducibility was 4.4% and 6.7%. The assay method was confirmed to have good reproducibility.2) Time-and temperature-related changes in urinary 6-HMP concentrations were investigated, and there were no changes for up to 24 hrs.3) In the daily profile of urinary 6-HMP concentrations, there were minimal changes, which did not influence the significance of measurement. It is therefore possible to use urine samples taken as needed.4) In a study of 76 samples of healthy human urine, the normal cutoff value for 6-HMP was 0.370μg/ml. There was no difference with respect to age or sex.5) In 32 cases of oral and maxillofacial malignant tumors, the mean and standard deviation was 0.669±0.370μg/ml.Our results indicate that the measurement of urinary 6 -HMP may be useful in the diagnosis of malignant tumors arising in the oral and maxillofacial region.