SERIAL TISSUE POLYPEPTIDE SPECIFIC ANTIGEN DETERMINATIONS IN THE FOLLOWUP OF HORMONE TREATED CARCINOMA OF THE PROSTATE

Abstract

We determined the impact of serum cytokeratin-18-related tissue polypeptide specific antigen (TPS) in monitoring hormone treated carcinoma of the prostate. From 1991 to 1996, serial TPS and prostate specific antigen (PSA) determinations (3,882) in 443 hormone treated prostate carcinoma patients were correlated with the clinical course for a mean of 22 months. Elevated TPS levels were significantly associated with disease progression in hormone treated stage M1 carcinoma of the prostate (p = 0.001), even in high grade, PSA negative tumors. Post-therapy TPS declines following secondline therapy in hormone refractory prostate cancer patients (92) correlated significantly with subjective response (p = 0.001, PSA p = 0.02) and progression-free survival time (r_S = −0.76, PSA r_S = −0.32). A TPS decrease of more than 50% coincided with palliation in 90% of patients (PSA 64%) and predicted the best chance of a longer progression of free survival (p <0.00005, PSA p = 0.036). Vice versa, rising TPS levels (more than 20%) coincided with subjective response in only 1 of 37 patients (PSA 9 of 33). TPS may be a useful adjunct to PSA in monitoring hormone refractory, metastasized prostate cancer.