Physical exercise may have a direct effect on cancer that is as effective as drugs for treating patients with prostate cancer, even for those with advanced stages of the disease. Data on this hypothesis under investigation in a phase 3 clinical trial was presented at the 2016 American Society for Clinical Oncology (ASCO) Annual Meeting.
The benefits of exercise can go further than its known ability to improve the quality of life for people with cancer, explained Fred Saad, MD, urologist-oncologist and researcher at the University of Montreal Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada, and first author of the study. Saad believes that physical exercise directly affects cancer and is as effective as drugs for prostate cancer, even in advanced stages of the disease.
“Typical patients with metastases often become sedentary. It is thought that this affects cancer progression,” he said. Together with Robert Newton, PhD, professor at the Edith Cowan University Exercise Medicine Research Institute in Australia, Saad is leading the first international study that aims to demonstrate that exercise literally extends the life of patients with metastatic prostate cancer.
“Normally, patients at this stage have a life expectancy of 2 to 3 years. We want to reduce mortality by at least 22%, which represents [approximately] 6 months of longer survival. This is the equivalent benefit of a new drug. Exercise could therefore supplement available treatments inexpensively,” said Saad.
This phase 3 trial has already started in Ireland and Australia. It aims to enroll approximately 900 men with advanced prostate cancer.
“We will study exercise as if it were a drug added to standard treatments. All patients will be treated within the latest scientific knowledge for this type of cancer. They will continue to follow their therapies and take their medications. But half of the patients will receive psychosocial support with general recommendations on physical exercise. The other half will also follow a high intensity exercise program,” he explained.
Newton, an exercise medicine expert, has designed a specific strength and cardiovascular training program for patients in the exercise group.
“They will have an hour of aerobic and resistance training 3 times a week. An exercise specialist will supervise them for the first 12 months, and then they will continue without direct supervision. We will evaluate quality of life, appetite, and treatment tolerance in relation to their improved physical condition,” said Newton, who is co-director of the Edith Cowan University, Exercise Medicine Research Institute.
The researchers will analyze blood samples and muscle biopsies to better understand the benefits of exercise.
“People with cancer develop all sorts of complications related to metastases, such as fractures or severe pain. It is hoped that exercise will strengthen muscles and bones,” said Saad.
The hypothesis is that exercise has a direct impact on cancer progression in addition to helping patients better tolerate therapy. Ultimately, they will live longer. The results of this large study, which involves some one hundred researchers in Canada, the United States, Australia, Ireland, the Netherlands, and the United Kingdom, will not be known for 5 years.
1. Saad F, Kenfield SA, Chan JM, et al. Intense exercise for survival among men with metastatic castrate-resistant prostate cancer (INTERVAL – MCRPC): a Movember funded multicenter, randomized, controlled phase III study. J Clin Oncol. 2016;34(suppl):Abstr TPS5092.