Influence of transrectal hyperthermia on prostate-specific antigen in prostatic cancer and benign prostatic hyperplasia.

The prostate-specific antigen (PSA) is a glycoprotein synthesized exclusively by the prostate. Since manipulations on the prostate can increase PSA serum levels, we investigated the effects of transrectal hyperthermia on PSA levels in prostate cancer (PC) and benign prostatic hyperplasia (BPH). Patients and treatments were the following: group 1a, PC St.D (n = 12): 8 hyperthermia sessions (twice a week) and LHRH-agonists plus flutamide; group 1b, PC St.D (hormone resistant; n = 10): 8 hyperthermia sessions (once a week) and epirubicin (50 mg intravenously, once a week); group 1c, PC St.C (n = 5): 6 hyperthermia sessions (once a week) and radiotherapy (60 Gy); group 2, BPH (n = 10): 8 sessions (twice a week). PSA levels were determined before, during (immediately before each hyperthermia session) and 1 week after therapy. Apart from hormone-/hyperthermia-treated patients, who showed a continuous decrease in PSA during therapy, all the other groups revealed a transient increase in PSA during the hyperthermia treatment. This effect is attributed to manipulations on the prostate and hyperthermia-specific effects on prostatic cells. The decrease in PSA on hormone/hyperthermia therapy can be explained by the tremendous effect of androgen deprivation on PSA levels overshadowing the hyperthermia effect.