In a randomized study we compared the combination of orchiectomy and radiotherapy to radiotherapy alone as treatment for locally advanced prostate cancer. Patients who were treated only with radiotherapy initially underwent castration therapy at clinical progression, providing the opportunity to compare immediate vs deferred endocrine intervention.

In this prospective study 91 patients with locally advanced prostate cancer were randomized to receive external beam radiotherapy (46) or combined orchiectomy and radiotherapy (45) after surgical lymph node staging. Survival rates were calculated.

During 14 to 19 years of followup 87% of the patients in the radiotherapy group and 76% in the combined orchiectomy and radiotherapy group died (log rank p = 0.03). Prostate cancer mortality was 57% and 36%, respectively (log rank p = 0.02). The difference in favor of combined treatment was mainly caused by lymph node positive tumors. For node negative tumors there was no significant difference in the survival rates.

Immediate androgen deprivation should be considered instead of deferred endocrine treatment started at clinical progression for prostate cancer with spread to regional lymph nodes. While awaiting evidence from randomized trials, one should consider full dose radiotherapy for local control of locally advanced prostate cancer even when it is lymph node positive.