Obesity linked to prostate cancer

Obese men are more likely to have precancerous changes detected in benign prostate biopsies and are at increased risk for eventually developing prostate cancer, new research suggests.

For the study, researchers examined data from nearly 500 men who were followed for 14 years after undergoing an initial prostate biopsy that was found to be noncancerous, or benign.

Prostate abnormalities were detected in 11% of the patients, and these abnormalities were strongly associated with obesity, said study author Andrew Rundle, an associate professor of epidemiology at Columbia University Mailman School of Public Health in New York City.

After taking into account factors including family history of prostate cancer, the researchers concluded that obesity at the time of the initial biopsy was associated with a 57% increased risk of developing prostate cancer during the 14 years of follow-up.

This association, however, was seen only for prostate cancer that occurred earlier in the follow-up period, according to the study, which was published in the issue of the journal Cancer Epidemiology, Biomarkers & Prevention.

Body size and prostate size

"We don't absolutely know what the true biology is," Rundle said. "In some ways, this reflects the association between the body size and larger prostate size, which is thought to reduce the sensitivity of the needle biopsy. It is possible that the tumours missed by initial biopsy grew and were detected in a follow-up biopsy."

The association found in this study does not prove cause and effect.

Rundle noted that previous studies "have attempted to determine if there are subpopulations of men diagnosed with benign conditions that may be at a greater risk for developing prostate cancer. This is one of the first studies to assess the association between obesity and precancerous abnormalities."

These findings indicate that obesity "should be considered a factor for more intensive follow-up after a benign prostate biopsy," Rundle said.

More information

The American Cancer Society has more about prostate cancer.