This phase 3 trial aims to determine if androgen suppression along with high dose proton radiation therapy offers more benefit than proton radiation therapy alone. The main outcome investigated is freedom from treatment failure.
The details
Freedom from treatment failure represents successful treatment with no local cancer recurrence, regional recurrence, distant metastasis or biochemical failure (> 2 ng/mL rise in prostate-specific antigen - PSA after treatment).
Proton beam radiation therapy is a new method of treatment for prostate cancer that involves a new type of radiation. It may be safer than the standard radiation treatment due to the possibility of better directing the radiation beams away from healthy tissue.
Androgen suppresion, or androgen depriving therapy (ADT) involves giving drugs that lower testosterone levels in the body. This leads to better prostate cancer outcomes. Drugs used for ADT include: leuprolide, goserelin, buserelin and triptorelin.
Who are they looking for?
Researchers are looking for about 192 prostate cancer patients with an intermediate risk of recurrence after treatment. The international prostate symptom score (IPSS) should be under 16.
Patients cannot participate if they have cancer spread to the lymph nodes, received other previous treatments for prostate cancer, have bowel disorders, history of other cancers within 5 years before the start of the trial, blood thinner medication that cannot be stopped or heart attack in the past 6 months.
How will it work
Patients will be assigned to one of two study groups. One group will receive proton beam radiation therapy (total dose 70 Gray) and androgen suppression. Androgen suppression will begin 8 - 10 weeks prior to the start of radiation treatment and will continue for a total of 6 (+/- 2) months. The second group will receive proton beam radiation therapy alone (total dose 70 Gray).
The main outcome investigated is the freedom from treatment failure.
