Objectives: The time to testosterone recovery after the cessation of androgen deprivation therapy appears to be dependent on the therapy duration. Most men will recover normal testosterone levels within 18 months according to the findings from studies that frequently involved fewer than 3 years of androgen deprivation therapy. Our goal was to assess the proportion of patients who remain castrated after cessation of longer duration luteinizing hormone-releasing hormone (LHRH) agonist therapy for prostate cancer.
Methods: We reviewed 15 patients who had received at least 48 months of continuous goserelin injection therapy for prostate cancer and had not been receiving the therapy for at least 18 months. The serum testosterone and prostate-specific antigen data were obtained.
Results: The mean duration of LHRH agonist therapy was 73 months (range 48 to 110). At the cessation of therapy after a mean follow-up of 31 months, 53% had testosterone levels that remained castrated. Only 1 patient achieved normal testosterone levels. Of the patients with greater than castrate testosterone levels, 71% experienced a prostate-specific antigen rise. All the men with an intact prostate who had testosterone recovery to greater than castrate levels had a prostate-specific antigen increase, which might represent a return toward the pretreatment baseline. Of the patients who started therapy after age 70 years, 78% remained castrated versus 17% of those who started before 70 years.
Conclusions: Of the men who had received 4 or more years of LHRH agonist therapy for prostate cancer, 53% remained castrated up to 2.5 years after therapy cessation. Patients who started LHRH agonist therapy after age 70 were more likely to remain castrate after stopping long-term therapy.