Prostate specific antigen progression rates after radical prostatectomy or radiation therapy for localized prostate cancer.

Abstract

The purpose of the study was to determine whether a difference is noted in the rate of prostate specific antigen (PSA) elevation after radical prostatectomy or radiation therapy for localized prostate cancer. PSA doubling times were calculated by linear regression analysis in 50 patients who had been treated by radical prostatectomy and who had three or more increasing PSA levels and in 55 patients who had been treated with radiation therapy and who had three or more increasing PSA levels. No significant difference was noted in the mean PSA doubling times in the two patient groups when stratified by the site of tumor recurrence or by pretreatment tumor stage, tumor grade, or acid phosphatase level. Because the PSA doubling time probably parallels the tumor growth rate, these data suggest that the malignant potentials of recurrent tumor after radical prostatectomy and after radiation therapy are equivalent.