Exercise Therapy and Radiation Therapy (EXERT) for Metastatic Prostate Cancer

In 2018, 30,000 patients were diagnosed metastatic prostate cancer in the US. Short-course radiation therapy (RT) is a mainstay of treatment for symptomatic metastases, and it stimulates an immune response against the tumor. However, RT also decreases systemic interleukin-1 receptor antagonist (IL-1Ra), placing the body in a pro-inflammatory state, and increasing fatigue and reducing quality of life (QOL). Fatigue and QOL are surrogates of the limited 2-20 month survival time. If fatigue and quality of life are improved, then toxicity and survival will follow. Our long-term goal is to identify the potential for exercise therapy (ET) to improve RT treatment toxicities and outcomes among men diagnosed with metastatic prostate cancer metastatic to distant sites or regional lymph nodes. The mechanistic hypothesis is that adding ET training to RT decreases long-term systemic inflammation, mitigating toxicity thereby widening the therapeutic window. Objective 1. Quantify the potential of Exercise Therapy (ET) to mitigate Radiation Treatment (RT) toxicities and physical function decline. The hypothesis is that ET mitigates patient-reported quality of life (QOL) and toxicities of RT. Our approach will be to use standardized questionnaires and assessment tools to assess QOL and physical function. Objective 2. Characterize the immunologic mechanism by which ET mitigates RT toxicity. The hypothesis is that ET mitigates the toxicity of RT (measured in objective 1) by increasing serum interleukin-1Ra (IL-1Ra). Objective 3. Evaluate the ability of ET to improve survival. Since physical function is a surrogate of survival, the hypothesis is that adding ET to RT will improve overall survival, measured from the date of start of radiotherapy until death.