Protocol for a 4-arm randomized controlled trial testing remotely delivered exercise-only, diet-only, and exercise + diet interventions among men with prostate cancer treated with radical prostatectomy (Prostate 8-II).

Background: Nutrition and physical activity are associated with prostate cancer recurrence and mortality. Few randomized controlled trials (RCT) have examined the effects of long-term exercise and diet changes on prostate cancer clinical, biological, and patient-reported outcomes.

Methods: Prostate 8-II is a 4-arm RCT among 200 men with prostate cancer who chose radical prostatectomy (RP) as their primary treatment. Men are enrolled prior to RP and randomized to exercise-only, diet-only, exercise + diet, or usual care (50/arm). Participants begin their assigned intervention 0-5 weeks prior to RP and continue for 24-months following surgery. The 3 active intervention arms receive access to a web-portal and text messages, coaching calls, and other intervention resources (e.g., heart rate sensor and resistance bands and/or recipe booklet). Weekly exercise goals for the exercise intervention groups are 150 min moderate or 75 min vigorous aerobic exercise, 2 strength sessions, and 2 flexibility sessions. Diet intervention groups work with a dietitian to customize their goals (e.g., increase cruciferous vegetables, cooked tomatoes, healthy fats, fish; limit processed meats, whole milk). The primary endpoint is biochemical recurrence. Secondary endpoints include change in tumor biomarkers from biopsy to RP as well as patient-reported outcomes (e.g., quality-of-life), blood and urine biomarkers, and anthropometry at 0, 6, 12, and 24 months.

Conclusion: This 4-arm RCT will examine the impact of change in exercise and diet (alone or in combination) on prostate cancer recurrence, biology, and quality-of-life.