Prostate Cancer Study:

Typically, proton therapy for prostate cancer is given over an eight-week period with 39 treatments. There is new evidence from the UF Health Proton Therapy Institute that a six-week, 28-treatment course of proton therapy is highly effective and achieves excellent prostate cancer patient outcomes.

The article, Five- and seven-year outcomes for image-guided moderately accelerated hypofractionated proton therapy for prostate cancer published in Acta Oncologica, details outcomes of the first 582 men treated between 2008 and 2015 on a prospective outcomes tracking trial at the UF Health Proton Therapy Institute for either low-risk or intermediate-risk prostate cancer. The study was led by principal investigator Randal Henderson, MD, MBA, Associate Medical Director of the UF Health Proton Therapy Institute and Professor of Radiation Oncology, University of Florida College of Medicine.

Notably, at five years after treatment, the rate of freedom from biochemical progression (FFBP) overall was 96.8%. At seven years after treatment, the rate was 95.2%. FFBP is measured by the level of prostate-specific antigen in the blood; a persistently low PSA following treatment with no worrisome rise indicates there is no evidence of active prostate cancer at that time. 

For low-risk prostate cancer patients, the FFBP rates at five- and seven-years were both 98.8%. For intermediate-risk prostate cancer patients, the FFBP rates at five- and seven-years were, respectively, 95.0% and 91.9%.

In further analysis, the researchers identified two subsets of intermediate-risk patients: favorable intermediate-risk and unfavorable intermediate-risk. The FFBP rates for favorable intermediate-risk patients at five- and seven-years were, respectively, 97.2% and 95.2%; for unfavorable intermediate-risk patients 93.1% and 88.8%.

Moreover, there were few side effects or complications with the shorter course of treatment. Researchers noted minimal physician-assessed toxicity and excellent patient-reported outcomes. The rate of mild gastrointestinal issues, such as those that required medication, at five- and seven-years were, respectively, 9.9% and 11.2%. For moderate gastrointestinal issues, such as those that required transfusion or hospitalization, the rates at five- and seven-years were both 1.4%. The rate of genitourinary issues that required some medical intervention at five- and seven-years were, respectively, 1.3% and 2.1%.

As men who are recently diagnosed with prostate cancer look for the best treatment option, the shorter course of proton therapy may offer them the benefits of a highly effective, safe treatment that saves them time and money.