Summary— A 2-stage study has been carried out to evaluate the usefulness of urinary tissue polypeptide antigen (TPA) levels in patients with bladder cancer as an adjunct to the routine procedures for detection of bladder tumours. Two-hour urine samples were collected from 83 bladder cancer patients and normal individuals for the first part of the study, 24-h samples from 54 patients and normal individuals for the second part. Urinary TPA was determined using radio immunoassay. In 2-h samples there was no significant difference in the amounts of TPA/I in any of the groups.

In contrast, the TPA results of 24-h urine samples (n = 54) were markedly different from 2-h samples and the former correlated very well with the presence or absence of bladder cancer. A reason for this difference may be circadian rhythm effects