Obesity associated with prostate cancer

Men with a higher body mass index (BMI) are more likely than thinner men to be diagnosed with prostate cancer, although it is less readily apparent on screening, and to have higher grade disease, according to a report in the July issue of Urology.

“Obesity may actually be associated with an increased risk of developing prostate cancer, but various features among obese men make it harder to detect the cancer,” Dr. Stephen J. Freedland from Johns Hopkins School of Medicine, Baltimore, Maryland explained to Reuters Health. “If you do find them, it’s probably the more aggressive cancers that you are finding.” Dr. Freedland and colleagues evaluated the association of BMI with prostate cancer and various other factors using data from 787 consecutive men undergoing prostate biopsy at Palo Alto Veterans Affairs Medical Center, Palo Alto, California. Overall, BMI did not appear to be associated with the odds of being diagnosed with prostate cancer. However, the authors report, a higher BMI was significantly associated with an increased odds of being diagnosed with prostate cancer after adjustment for PSA concentration, digital rectal examination (DRE) findings, prostate volume, and race. Men with a BMI above 35 faced a 2.4-fold higher risk of being diagnosed with prostate cancer, compared with normal weight men, the report indicates. Higher prostate volume in obese men was the greatest contributor to obscuring the association between BMI and prostate cancer development, the researchers note. After adjustments for PSA concentration, DRE findings, prostate volume, and race, a higher BMI was also associated with a significantly increased odds of a high Gleason sum, the investigators report. Specifically, the odds of having a high Gleason score were more than doubled with a BMI of 30 to 35, and quadrupled with a BMI of 35 or higher.”Be hypervigilant in looking for prostate cancer among obese men,” Dr. Freedland advised. He recommended “standard PSA yearly, keeping in mind that the level may be lower than you’d expect. You might want to use a lower cutpoint for recommending biopsies.” “Protocols may not adjust well for prostate size,” Dr. Freedland added. “Prostate size may be more important than we realize, so the biopsy protocol might need to be modified to account for that. More cores might increase the likelihood of finding prostate cancer,” he suggested,”Whether more intensive screening can reduce the increased prostate cancer mortality observed among obese men in the pre-PSA and early PSA eras remains to be determined,” he and his colleagues conclude in their paper.(Source: Urology 2005;66:108-113: Reuters Health: Oncolink: August 2005.)