Serum tissue polypeptide antigen (S‐TPA) in bladder cancer as a tumor marker. A prospective study

Background. Tissue polypeptide antigen (TPA) is a differentiation and a proliferation tissue marker of non‐squamous epithelia. Increased urinary and serum TPA (S‐TPA) levels were found in some patients with invasive bladder cancer. The authors report the results of a prospective study evaluating the role of serum TPA (S‐TPA) in bladder carcinoma. Methods. S‐TPA concentrations were measured by radioimmunoassay in 53 patients with invasive bladder tumor before treatment, at the end of treatment, and during follow‐up. The upper normal limit of the test was set at 80 UI/ml. Results. With a specificity of 100%, the diagnostic sensitivity of the test was 54.7%. S‐TPA was increased in 88% of patients with N1 + N2 disease compared with 38.8% of the patients with N0 disease (P = 0.01) and in 100% of patients with metastatic disease and 48% of patients with nonmetastatic disease (P = 0.01). S‐TPA was increased in 23% of patients with total macroscopic debulking and in 68% of patients with persistent macroscopic disease (P = 0.004). For patients staged N0 M0, no statistical correlation between S‐TPA level and debulking by transurethral resection (TUR) was found (P = 0.15). In the subset of patients with normal pretherapeutic S‐TPA levels, 75% achieved a complete response, compared with 44.8% of the patients with initial elevated S‐TPA levels (P = 0.04). However, there was no statistically significant relationship between pretherapeutic S‐TPA levels and immediate response to treatment according to the stratification for tumor volume after initial debulking by TUR. For a mean follow‐up of 15 months ± 7 months, median survival time and 1‐year survival rates were studied in the subset of patients with limited disease (N0 M0) according to the pretherapeutic S‐TPA levels. The median survival time was not reached, and the 1‐year survival rate was 80% when the initial S‐TPA level was normal; these were 10 months and 44%, respectively, when the S‐TPA level was high (P < 0.01). Among the 31 patients who achieved a complete response, 9 experienced a relapse, with an increase of the S‐TPA level in 8 patients. Conclusions. The S‐TPA level is correlated with initial tumor volume. It appears to be a prognostic factor and a valuable parameter for follow‐up.