P53 AUTOANTIBODIES IN PATIENTS WITH UROLOGICAL TUMORS

Objective To determine the presence of p53 serum antibodies in patient s with clinically well-defined urological cancer using a new enzyme-li nked immunosorbent assay (ELISA). Patients and methods The study inclu ded 73 patients with prostatic cancer, 72 with transitional cell carci noma of the urinary tract, 37 with renal cell cancer and 16 controls w ith a benign disease, all of whom were tested using the ELISA for p53 autoantibodies. The specific reaction of the ELISA (positive p53 antib ody titre) was confirmed by Western Blot analysis. Results Thirteen pa tients with cancer and one control patient (7.6% overall) were positiv e for p53 autoantibodies. The sensitivity of the test was low, whereas the specificity was remarkably high. Surprisingly, 9 of the 13 p53-po sitive patients died within a median of 3.7 months (range 2-6) and the one positive control patient died of undetected lung cancer. There wa s no significant correlation of p53 antibody positivity with clinical stage or tumour-specific differences. Conclusions The expression of p5 3 autoantibody seems to be a very late but significant event in urolog ical tumour development, with the worst outcome (tumour-specific death ) within a few weeks of developing positivity. In histopathologically heterogeneous tumour entities, p53 autoantibodies might be independent prognostic factors in patients with urological cancers.