Comparative Health Research Outcomes of NOvel Surgery in Prostate Cancer

Men diagnosed with significant cancer confined to the prostate currently undergo radical therapy directed to the whole prostate (radiotherapy or prostatectomy). These provide good cancer control but can cause significant side effects. Focal Therapy involves targeting the cancer alone, whilst leaving healthy prostate gland alone. Case series have shown similar cancer control over 5 years with a much better side effect profile. However, there have been no randomised control trials (RCTs) comparing the success in cancer control and the quality of life in patients that undergo radical therapy vs those that undergo focal therapy. Further, there is a need to assess the use of additional therapies that may improve the cancer control outcomes following focal therapy. By having a trials platform with two RCTs (CHRONOS-A and CHRONOS-B) that reflect best patient and physician preferences/ equipoise, the investigators aim to answer these questions. To improve acceptability, recruitment and compliance, the investigators have an embedded study aimed at reviewing clinician and patient perspectives and trial acceptability. CHRONOS-A will compare radical therapy to focal therapy, whilst CHRONOS-B will compare focal therapy alone to focal therapy with various therapies targeting the testosterone pathway that can shrink the cancer before it is treated. The investigators think this might improve outcomes further for men that definitely want focal therapy.