Men concerned about reducing their risk of prostate cancer may want to start by checking themselves out in front of a full-length mirror. It's not just that weight is a risk factor for this form of cancer, but according to a new study, where a man carries his excess pounds matters, too. Certain patterns of fat accumulation are associated with a greater risk of prostate cancer and a poor outcome after diagnosis, the study by researchers at Harvard found.
Researchers analyzed data on 1,832 men enrolled in a population-based study done in Iceland known as the Ages, Gene/Environment Susceptibility Reykjavik study. This was a prospective study — none of the men in the study had prostate cancer when the study began. Over a four-year period, each man's body fat distribution was determined, using computed tomography (CAT) imaging. Each participant's body mass index (BMI) and waist circumference were also measured.
Then, over a follow-up period of up to 13 years, they looked to see if there was an association between these measurements and scans and a man's risk of being diagnosed with and dying from prostate cancer.
The more belly or visceral fat — fat deep in the abdomen and surrounding the internal organs — a man had, the higher his risk of being diagnosed with advanced prostate cancer.
A high BMI and a large waist circumference were also linked to an increased risk of advanced and fatal disease, but when the researchers compared men with a high BMI to those with a low BMI in a separate related study, accumulated visceral fat was more strongly associated with an increased risk of advanced prostate cancer and death from prostate cancer in men with a lower BMI.
“Interestingly, when we looked separately at men with a high BMI versus low BMI, we found that the association between visceral fat and advanced and fatal prostate cancer was stronger among men with a lower BMI,” Barbra Dickerman, lead author on the study, noted.
Body fat distribution may be an important predictor of the risk of advanced and fatal prostate cancer, Dickerman told TheDoctor in an email, adding that the hope is that, “This information may identify men for targeted intervention strategies.”
Going forward, the team is looking to see if measures of fat distribution can be used “to tailor lifestyle interventions to improve prostate cancer outcomes,” said Dickerman, a research fellow at the Harvard T.H. Chan School of Public Health.
More studies are needed to assess the role of fat distribution in prostate cancer outcomes, especially how changes in fat distribution over time affect prostate cancer risk. Identifying patterns of fat distribution associated with the highest risk of clinically significant prostate cancer may also help to zero in on the mechanisms linking obesity with aggressive forms of the disease.
The study is published in Cancer.