• Disease-specific survival (i.e., death due to prostate cancer) [ Designated as safety issue: No ]
  

• Freedom from treatment failure [ Designated as safety issue: No ]
  
• Clinical progression-free survival [ Designated as safety issue: No ]
  
• Overall survival [ Designated as safety issue: No ]
  
• Non-protocol hormone therapy [ Designated as safety issue: No ]
  
• Treatment toxicity [ Designated as safety issue: Yes ]
  
• Patient reported outcomes [ Designated as safety issue: No ]
  

OBJECTIVES:

• Assess the timing of radiotherapy and the use of hormone therapy in conjunction with post-operative radiotherapy.
• Determine the impact of radiotherapy on general quality of life, sexual function, urinary function, and bowel function.
• Determine the impact of duration of hormone therapy on general quality of life and sexual function.

OUTLINE: This is a multicenter study. Patients requiring immediate radiotherapy (RT) are assigned to arm I; patients do not require immediate RT are assigned to arm II. Patients for whom the need of immediate post-operative radiotherapy are uncertain undergo radiotherapy timing randomization within 3 months after surgery and are randomized to 1 of 2 radiotherapy arms.

• Arm I (immediate RT): Within 2 months after randomization, patients undergo radiotherapy to the prostate bed once a day, 5 days a week, for 4 (20 fractions total) or 6.5 weeks (33 fractions total). They may also undergo radiotherapy to the pelvic lymph nodes once a day, 5 days a week, for 4.5 weeks (23 fractions total) at the investigator's discretion.
• Arm II (early salvage RT in case of PSA failure): Within 2 months of confirmation of post-operative biochemical failure, patients undergo radiotherapy as in arm I.

Patients undergoing immediate RT and patients who eventually need early salvage RT undergo hormone therapy duration randomization before the administration of post-operative radiotherapy. Patients are randomized to 1 of 3 hormone therapy arms.

• Arm III (no hormone therapy): Patients do not receive hormone therapy. They receive post-operative RT alone as described above in arm I or II.
• Arm IV (RT and short-term hormone therapy): Beginning approximately 2 months prior to the start of RT, patients receive hormone therapy for 6 months. Hormone therapy* may comprise of LHRH agonist (gonadotrophin-releasing hormone analogue [GnRHa] [e.g., goserelin or leuprolide acetate]) or bicalutamide daily.
• Arm V (RT and long-term hormone therapy): Beginning approximately 2 months prior to the start of RT, patients receive hormone therapy for 24 months. Hormone therapy* may comprise of LHRH agonist (gonadotrophin-releasing hormone analogue [GnRHa] [e.g., goserelin or leuprolide acetate]) or bicalutamide daily.

NOTE: *For Canadian patients, hormonal therapy will consist of LHRH analog (leuprolide acetate) therapy only.

Treatment continues in the absence of disease progression or unacceptable toxicity. Quality of life is assessed using self-administered questionnaires at baseline and 1, 5, and 10 years after randomization. Health economics information is also collected via patient-administered questionnaires (EQ-5D) at baseline and at 1, 5 and 10 years after randomization.

After completion of study treatment, patients are followed for 7 years.