[Tissue polypeptide antigen (TPA) in urological malignancies. I. S-TPA in bladder cancer patients]

Serum tissue polypeptide antigen (S-TPA) levels in 22 patients with bladder cancer were determined using a radioimmunoassay kit by the two-antibody technique to evaluate the usefulness of this parameter as an index of the presence of cancer. As S-TPA values (mean +/- SD) in 72 Japanese normal blood donors (37 male and 35 female) were in the range of 32.4-97.2 units per liter, values higher than 97.2 u/l were considered positive. We found a remarkably increased level of S-TPA in 14 out of 18 (77.8%) patients with untreated cancer and a slightly increased level of S-TPA in 3 out of 4 patients whose tumors had been removed. Elevated S-TPA levels in patients who had tumors remaining were suggested to correlate with histological stage and grade of tumors, type of growth and size of tumors, although not to correlate with number of tumors and whether tumor occurrence was initial or recurrent. Simultaneous urinary cytological examination and measurement of plasma CEA in the same patients gave the positive ratio of 7/16 (43.8%) and 0/14 (0%), respectively. It is possible that S-TPA may be one of the most useful tumor markers in the screening of cancer, diagnosis of histological characteristics, monitoring of cancer therapy and detection of recurrence.