Exercise linked to cardiorespiratory benefit, lower PSA level in men with prostate cancer
Exercise appeared associated with decreased PSA levels, PSA velocity and prostate cancer cell growth in men with localized prostate cancer under active surveillance, according to a randomized study published in JAMA Oncology.
Results of the Exercise During Active Surveillance for Prostate Cancer (ERASE) trial showed high-intensity interval training (HITT) also may be an effective intervention to improve cardiorespiratory fitness among this patient population.
“Right now, there is nothing these men can really do for themselves other than attend all of their follow-up medical visits. We wanted to see if a high-intensity interval training exercise program might not only improve their fitness, but also possibly delay the progression of their prostate cancer,” Kerry S. Courneya, PhD, professor and Canada research chair in physical activity and cancer and director of the behavioral medicine laboratory and fitness center at University of Alberta, told Healio.
“Many men with prostate cancer on active surveillance are keen to engage in nonmedical interventions to improve their health and possibly delay or prevent the progression of their prostate cancer,” Courneya added. “Lifestyle interventions, such as exercise, are feasible for these men and may improve clinical outcomes, but more research is needed.”
The analysis included 52 men (mean age, 63,4 years; standard deviation, 7.1; 89% white) diagnosed with localized very low-risk to favorable intermediate-risk prostate cancer and undergoing active surveillance. Researchers randomly assigned half of the men to the HIIT group and half to the usual-care group.
Men in the HIIT group had to complete a 12-week, thrice-weekly supervised exercise program — customized based on each man’s baseline cardiopulmonary fitness — on a treadmill at 85% to 95% of peak oxygen consumption, with intensity and duration of exercise increasing over time.
Men randomly assigned to the usual-care group were asked not to alter their exercise levels during the intervention period.
Peak oxygen consumption served at the primary outcome, assessed as the highest value of oxygen uptake during a graded exercise test using a modified Bruce protocol. Secondary outcomes included PSA concentrations and kinetics, PSA velocity, sex hormone levels, functional fitness and anthropometrics.
Researchers reported 96% adherence to HITT. Eighty-eight percent of participants completed the postintervention peak oxygen consumption assessment and 94% provided blood samples.
Results showed peak oxygen consumption increased by 0.9 mL/kg/min in the HIIT group and declined by 0.5 mL/kg/min in the usual-care group (adjusted between-group mean difference = 1.6 mL/kg/min; 95% CI, 0.3-2.9). Additionally, the HIIT group experienced reductions in PSA level (1.1 µg/L; 95% CI, 2.1 to 0), decreased PSA velocity (1.3 µg/L/y; 95%CI, 2.5 to 0.1) and decreased LNCaP cell growth (0.13 optical density unit; 95% CI, 0.25 to 0.02) compared with the usual-care group.
Researchers reported no statistically significant differences in PSA doubling time or testosterone between the groups.
“We thought the fitness changes might have been a bit larger, but many of these men were fairly healthy and fit at baseline,” said Courneya, who credited former University of Alberta PhD student Dong-Woo Kang, PhD, now a postdoctoral fellow in the department of medical oncology at Dana-Farber Cancer Institute, for leading the research.
More research in active-surveillance clinical settings is needed to identify biophysiological associations between exercise and prostate cancer, as well as to explore potential tumor-related biomarkers, the researchers wrote. Meanwhile, they plan to report more results from the ERASE trial.
“We have collected and submitted for publication additional data in the ERASE trial on patient-reported outcomes such as prostate cancer-specific anxiety, perceived stress, fear of cancer progression and quality of life,” Courneya told Healio. “We also assayed other blood markers, such as immune markers, inflammation and lipids, which we will report in future papers. The next steps after ERASE are larger phase 2 and phase 3 trials powered for clinical outcomes, but these trials will require multicenter collaboration.”
Although it was not powered to examine OS, the ERASE trial empowers this population of patients “to be in better physical, functional and psychological shape for any future medical interventions they may need,” Neha Vapiwala, MD, professor of radiation oncology at Perelman School of Medicine at University of Pennsylvania, wrote in a commentary accompanying the study.
“Ultimately, the ERASE trial is well-constructed and demonstrates the power of a lifestyle intervention with far-reaching implications,” Vapiwala wrote. “Although the specific focus on patients pursuing [active surveillance] is technically not unique, it is uncommon; demonstration that HIIT alone, without dietary changes, resulted in improved cardiorespiratory fitness and biochemical parameters in men with localized prostate cancer on active surveillance and growth inhibition at the cellular level is novel and noteworthy.”
For more information:
Kerry S. Courneya, PhD, can be reached at Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-113 University Hall, Edmonton, Alberta T6G 2H9, Canada; email: firstname.lastname@example.org.