CORRELATION OF CELL-PROLIFERATION MARKER (TPS), NATURAL-KILLER (NK) ACTIVITY AND TUMOR LOAD SEROTEST (PSA) IN UNTREATED AND TREATED PROSTATIC TUMORS

Tissue polypetide specific antigen (TPS) is a new tumor proliferation serotest marker. The respective radioimmunodetective procedure is base d on the application of monoclonal antibodies raised against one the p rinciple epitopes of tissue polypeptide antigen (TPA). TPS is useful t ool for the identification of proliferative epithelial cells and is ne gative in all non-epithelial tissues such as lymph nodes, bone marrow, carcino-sarcomic and neuroendocrine prostatic tumors. In previous stu dies we have shown the clinical usefulness of this serotest in serial measurements during prostatte cancer monitoring. In this study serum p rostatic specific antigen (PSA) concentrations and natural killer (NK) cell activity data were compared with serum TPS values in a wide spec trum of prostate cancer condisiton (99 patients), benign prostatic hyp ertrophy (BPH, 40 patients), atypical prostate (12 subjects) and in 8 healthy men. Measured parameters reflect different aspects of the dise ase. Blood PSA concentrations and TPS serot values were found to denot e the status of disseminated prostate cancer with nearly equal signifi cance, while PSA appears to be a more appropriate tumor marker in earl y stages of the disease. In atypical prostate a nonsignificant elevati on of both PSA and TPA values was recorded when compared with BPH. In parallel, a pronounced and sharp drop in NK activity data was assesed resembling closely respective data in progressive Stage D2 patients. T PS serotest clearly detects cancer progression in treated and untreate d patients (P < 0.01) while being less efficient in distinguishing bet ween tumor stabilization and partial remission (p>0.05). In this respe ct NK activity data serve as a sensitive probe for the presence of epi thelial tumor cells in the circulation even during stabilization of th e disease. According to the reported results we advocate the applicati on of the TPS serotest as a useful addition in monitoring progressive patients with advanced prostatic carcinoma.