Early versus delayed endocrine treatment of pN1-3 M0 prostate cancer without local treatment of the primary tumor: results of European Organisation for the Research and Treatment of Cancer 30846--a phase III study.

Purpose: The timing of endocrine treatment for prostate cancer remains controversial. The issue is addressed in protocol 30846 of the European Organisation for Research and Treatment of Cancer for patients with lymph node positive cancer without local treatment of the primary tumor.

Materials And Methods: A total of 302 patients with metastatic regional lymph nodes who had not received local treatment for the primary tumor were included in the trial, of whom 234 were randomized to immediate vs delayed endocrine treatment. Endocrine treatment consisted of an luteinizing hormone-releasing hormone agonist and 1 month of antiandrogen treatment or surgical castration. The main end point of the trial was overall survival. Analysis followed the intent to treat principle.

Results: At a median followup of 9.6 years (8.7 in the randomized sample) 190 patients (62.9%) had died, including 76% of prostate cancer. In the randomized sample the HR for survival on delayed vs immediate treatment was 1.23 (95% CI 0.88 to 1.71), indicating a 23% nonsignificant trend in favor of early treatment. However, the wide CI showed that results remained compatible with true effects, ranging from a 12% benefit in favor of delayed treatment to a 71% detriment for the same treatment approach.

Conclusions: While this study suggests an advantage for early treatment, it is under powered to show equivalence or superiority for the early or delayed approach. When dealing with individual patients, the potential survival advantage on early treatment must be balanced against potential advantages in quality of life on delayed treatment.