Obesity increases prostate cancer recurrence risk

Obese men, especially those obese at age 40 or at the time of diagnosis, face an increased risk of prostate cancer progression, according to a report in the October 1st issue of Clinical Cancer Research.

“At any age, but especially in the adult population, keeping a healthy weight and diet will not only help prostate cancer patients to potentially reduce the chance of the cancer to recur, but will also reduce their risk of cardiovascular disease and diabetes,” Dr. Sara S. Strom from The University of Texas M.D. Anderson Cancer Center, Houston, told Reuters Health.Dr. Strom and colleagues evaluated self-reported measures of obesity at different ages in a group of 526 prostate cancer patients treated with radical prostatectomy in an effort to develop a prognostic model of biochemical failure.Men who were obese at the time of diagnosis had marginally higher rates of biochemical failure, the authors report, but those who were obese at age 40 had significantly lower biochemical failure-free survival than did those who were not obese at age 40.Obesity between age 25 and 40 was associated with more than a doubling of the biochemical failure risk, the report indicates, as was an annual weight gain in excess of 1.5 kg/year between age 25 and the diagnosis of prostate cancer.Men who gained more weight since age 25 also experienced progression significantly sooner than those who gained weight more slowly or not at all, the researchers note.A nomogram incorporating body-mass index (BMI) proved a better predictor of biochemical failure than did a nomogram without BMI, the results indicate.”This nomogram will need to be validated in a larger multi-institutional series of patients followed for a longer period of time,” the investigators conclude.”We have initiated studies using murine models to identify the underlying mechanisms/pathways by which genes and environment (e.g., diet, physical activity) modulate prostate cancer progression,” Dr. Strom said. “In addition, the identification of these mechanisms will provide molecular targets for the development of pharmaceutical interventions.”In the meantime, Dr. Strom said physicians need “to pay attention to the level of obesity of the patients and to reinforce the need for strict follow-ups to monitor the disease. In addition, (they need) to take weight gain and obesity into consideration when discussing the possibility/need of additional treatments.”(Source: Clin Cancer Res 2005;11:6889-6894: Reuters Health: Will Boggs, MD: Oncolink: October 2005.)