Influence of clinical procedures on serum PSA and FPSA concentration

Objective:To evaluate the influence of clinical procedures on serum PSA and FPSA concentration.Methods:A total of 138 patients were studied prospectively,the effects of digital rectal examination(DRE),indwelling catheter,cystoscopy(rigid),prostate needle biopsy and prostatectomy on serum PSA and FPSA concentration were observed.Results:The PSA and FPSA changing caused by DRE was 0.18±1.36 ng/ml and 0±0.23 ng/ml respectively,neither was significant(P0.05).Indwelling catheter caused an 1.6-fold and 1.23-fold increase on PSA and FPSA(P0.05).Cystoscopy had the effects of 73% and 42% elevation on PSA(P0.01)and FPSA(P0.05).The PSA and FPSA concentration had an 1.04-fold and 1.74-fold increase after prostate biopsy(P0.01,0.05),and had more remarkable elevation(2.23-fold and 2.82-fold,P0.01)after TURP.Prostatectomy by open surgery caused an 2.32-fold increase on PSA(P0.05)and 2.28-fold increase on FPSA(P0.05).F/T values changed from-7% to 27% in all cases,but none of the change was significant.The serum PSA and FPSA concentration returned to the base level 4 weeks after the procedures,although some of the values seemed to be lowered by prostatectomy.Conclusions:DRE had no significant effects on serum PSA and FPSA concentration.PSA and FPSA concentration increased significantly after indwelling catheter,cystoscopy,prostate biopsy and prostatectomy.We recommend that it is prudent to wait for 4 weeks after these procedures before measuring the serum PSA and FPSA value.