Urinary excretion levels of seven unconjugated
pterins in healthy individuals and in
cancer patients, most of whom were undergoing
chemotherapy, were measured utilizing a newly developed high-pressure liquid chromatographic system. Excretion of
pterins in the control group appears to be under strict metabolic control as the values obtained were confined within a small range. When the mean excretion levels in control subjects were compared with those in
cancer patients, we found a significant increase in the excretion of
xanthopterin,
neopterin and
pterin and a significant decrease in
isoxanthopterin by
cancer patients.
Biopterin levels, on the other hand, were found only slightly but not significantly increased, whereas pterin-6-carboxylic
acid and
6-hydroxymethylpterin were found to be excreted in approximately equal amounts in both groups. Urinary excretion levels of
pterins were monitored for a period of nine months in a patient being treated with
chemotherapy for metastatic ovarian
carcinomatosis. We found that the excretion pattern of
pterins appeared to correlate with the clinical status of the patient. These results indicate that a definite imbalance in
pterin, and possibly
folate metabolism, is associated with the presence of malignant diseases.