Endocrine therapy for recurrence after definitive radiotherapy in patients with prostate cancer

Background: Long-term results were analyzed to evaluate the role of endocrine therapy in the management of local and distant recurrence of prostate cancer following external radiation therapy. Methods: Between 1976 and 1994, 92 patients with untreated prostate cancer underwent external beam radiation therapy alone. Endocrine therapy had been started when relapse was evident. Results: Failure was seen in 35 of 92 patients: 10 local, 19 distant and six biochemical failures. Endocrine treatment was performed in 28 patients with nine local and 19 distant failures. The cancer-specific survival rate from the endocrine treatment was 54.5% at 5 years. Prostate-specific antigen level in 20 of 20 patients (100%) decreased to below the normal limit 3 months after the start of endocrine therapy. In univariate analysis, T classification was the most significant variable for cancer-specific survival from the initial treatment. Conclusions: A favorable outcome was achieved by endocrine therapy in patients who had relapsed after external beam radiation monotherapy. Even the recurrent tumor had a sensitivity to androgen. Patients with locally advanced disease (T2b and T3) had poorer prognosis than those with minimally extended disease (T1b and T2a).