The investigators, from The University of Texas M. D. Anderson Cancer Center researchers, used standard clinical criteria for predicting the risk of treatment failure in patients treated for localized prostate cancer (cancer that is confined within the prostate) to assign the patients to different groups according to the likelihood that their cancer would progress. These criteria included pre-treatment PSA levels and biopsy Gleason scores (a score assigned by a pathologist to determine the aggressiveness of the cancer) and clinical T stage (the size of the tumor).
A total of 1,117 patients with localized prostate cancer were recruited over a six-year period and surveyed on their lifestyle, and these answers were then matched to their risk of progression.
The researchers found that patients with a high-risk of progression were significantly more likely to be obese, to exercise less than twice a week, and not to have had prior annual prostate cancer screenings. Those with the lowest risk kept their body weight down, exercised regularly and had routine screenings.
"What we are finding has positive implications for prostate cancer prevention," says the lead author, Mfon Cyrus-David, M. D., a postdoctoral fellow in the Department of Epidemiology. "It appears to be important that men maintain a low body mass index, exercise to the point of sweating at least two times a week, and be screened regularly for prostate cancer."
Although researchers say their conclusions are preliminary, and that their findings need further validation with a follow-up study, the study is among the first to attempt to quantify the predictive risk that lifestyle factors have on whether or not prostate cancer will recur in patients who have been treated.