Pseudouridine: a prognostic marker in non-Hodgkin's lymphomas.

: An increased excretion of pseudouridine, a modified nucleoside derived from degraded transfer ribonucleic acid, has been observed in patients with malignant lymphomas. This paper presents the analysis of pseudouridine in the urine from 39 patients with non-Hodgkin's lymphomas before treatment. Using the Kiel classification, 57% of the patients with highly malignant lymphomas had elevated excretion of pseudouridine, compared to 28% of patients with low-grade malignancy, and 4% in healthy adults. Subdividing the patients according to clinical stages, an increase of pseudouridine levels paralleled the disease manifestation. Of patients in clinical stages 3 and 4 with highly malignant lymphomas, 85% had elevated excretion. This observation, in combination with shorter survival seen in a group of 22 patients followed 37-61 months, suggests that elevated excretion of pseudouridine is a negative prognostic factor in non-Hodgkin's lymphomas. The level of pseudouridine in the urine gives useful information in staging and for prognosis.