Urinary pseudouridine/creatinine ratio as an indicator of gastrointestinal cancer

Urinary pseudouridine/creatinine ratio was determined in 74 patients with gastrointestinal tumours and 34 patients with no known malignant disease. The reproducibility of a single random urine sample was demonstrated. The mean ratio for control patients was 26.9 +/- 7.7 nmol/mumol and no control patient exceeded the mean by 2 standard deviations. There was no difference in the ratio between the sexes. Sixty-five per cent of colon cancer patients and 37.5 per cent of gastric and rectal cancer patients exceeded this upper limit of normality. There was no correlation between pseudouridine/creatinine ratio and histological differentiation, liver involvement or stage in either colorectal or gastric cancer patients. Urinary pseudouridine/creatinine ratio is one of the better non-specific cancer markers and may be particularly useful for detecting colonic cancer.