Effect of Transurethral Microwave Thermotherapy on Serum Concentrations of Total and Free Prostate-specific Antigen

This study includes 15 men between 48 and 81 years of age with treatment-requiring symptomatic benign prostatic hyperplasia (BPH). No patient with a urinary infection or prostate cancer was included. The serum concentrations of prostate-specific antigen (PSA), total as well as "free", i.e. noncomplex bound, were repeatedly determined before and up to 3 months after transurethral microwave thermotherapy (TUMT) of the prostate. After TUMT we found significant rises of the ratios of the serum total PSA concentration/prostate volume (up to 55-fold, mean 13.1) and of the serum free PSA concentration/ prostate volume (up to 26-fold, mean 10.2). The highest values for the serum total PSA concentration/prostate volume ratio were found on the first day after TUMT. Maximal serum free PSA concentration/prostate volume ratio occurred 3-6 h after treatment. The serum concentration/prostate volume ratios for total and free PSA returned to normal within 3 months. The results indicate that PSA determinations might be used as effect indicators of TUMT.