Role of Physical Activity and Its Link with Lower Rates of Progression in Men on Active Surveillance - Editorial
In this study, the authors assessed 85 men with low-risk prostate cancer being managed by active surveillance. All men completed a physical activity questionnaire at baseline and were categorized as sedentary (n=24), moderately active (n=46), or active (n=15). The authors then assessed the risk of grade reclassification, commonly used criteria for “progression” among men on active surveillance. The authors found that those who progressed were less physically active (p=0.056). Importantly, over time, the level of physical activity was significantly predictive of who progressed (p=0.033). Indeed, on multivariable analysis, the level of physical activity was the only significant predictor of progression (p=0.016). The authors concluded that physical activity may influence prostate cancer evolution.
While the results of this study are important and certainly support what many of us already believe (i.e. exercise is good), the limitations of the paper should first be noted. First – this is not a randomized trial. Thus, more active men have had other healthy behaviors (better diet, less smoking, etc.). Indeed, many of these other measures were not even collected. Thus, one cannot conclude that physical activity IS good, merely that it is associated with better outcomes. Second – the number of men was small. This lends itself to type 1 errors (significant findings are noted, but they are not “real”). Finally – the outcome was higher grade disease. Ideally, better measures of true tumor progression are needed, such as metastases, though this is fortunately rare in men on active surveillance.
These issues, notwithstanding, these data certainly suggest exercise may slow prostate cancer progression. Given the overall health benefits of exercise, coupled with data from this (and many other) studies suggesting prostate cancer benefits, perhaps next time the patients asks, “Will it help”, instead of saying “I don’t know”, we can reply “Probably”. I know that is not as satisfying as many of us would like, but in the absence of a large well-designed phase 3 randomized trial, “Probably” is still pretty good.
Written by: Stephen J. Freedland, MD, Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California
Read the Full-Text Article: Physical Activity Decreases the Risk of Cancer Reclassification in Patients on Active Surveillance: A Multicenter Retrospective Study