Prostate Cancer May Prefer Big Men

Prostate cancer may be more likely to develop in obese men who have had benign biopsies

(RxWiki News) Obesity increases a person’s risk of a variety of cancers. This connection now appears to affect men who have been tested for and found not to have prostate cancer.

A recent study found that obese men who have had benign (not cancer) prostate biopsies were more likely to have precancerous lesions than men of normal weight.

Obese men were also more likely to develop prostate cancer in the future than their peers who were not obese, the study discovered.

"Work with your MD to determine the best cancer screening options."

Andrew Rundle, DrPH, associate professor of epidemiology at Columbia University Mailman School of Public Health in New York, NY, led a study that looked at the links between obesity and the likelihood of developing prostate cancer.

A total of 6,700 men at the Henry Ford Health System were involved in the original study. Participants were followed for 14 years following a biopsy or surgical removal of the prostate that did not detect prostate cancer.

Researchers conducted a smaller case-control study that compared 494 study members with 494 healthy matched controls.

Precancerous abnormal growths called prostatic intraepithelial neoplasia (PIN) were found in 11 percent of the patients’ tissue samples.

According to Rundle, the abnormalities were associated with obesity.

Obese men had a 57 percent greater likelihood of developing prostate cancer than men who weren’t obese. This ratio was determined after factoring out family history of prostate cancer, initial PSA (prostate-specific antigen) levels and the number of PSA tests and digital rectal exams during the follow-up.

The obesity-prostate cancer association was only seen in tumors detected earlier in the follow-up period – within just over four years.

The biology behind these findings is not clearly understood. Body size and larger prostate make biopsies less sensitive. “It is possible that the tumors missed by initial biopsy grew and were detected in a follow-up biopsy,” Dr. Rundle said in a press release.

“The association of obesity and prostate cancer is controversial. This study suggests an increased risk,” prostate cancer expert E. David Crawford, MD, told dailyRx News.  

Previous studies have not found this great of an association. The researchers said the difference in findings may be that the study members were men at high risk of developing prostate cancer, and who were closely monitored with regular PSA tests and repeat biopsies.

“Obesity may be a factor to consider when planning the intensity of clinical follow-up of men after an initial benign procedure,” the authors concluded.

"We need to employ molecular markers to help us identify those at increased risk. We can use PCA3, MDX test and a new PSA assay called Pro PSA, said Dr. Crawford, who is professor of surgery, urology and radiation oncology, and head of the Section of Urologic Oncology at the University of Colorado Health Sciences Center in Denver.

Findings from the study were published April 23 in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research. This work was supported by a grant from the National Institute of Environmental Health Sciences.

Review Date: 
April 23, 2013