Diet Rich in Saturated Fat Makes Prostate Cancer More Aggressive

Secondary analysis of data from a retrospective study that found an inverse relation between statin use and the aggressive nature of prostate cancer has shown that high total fat-adjusted saturated fat intake increases disease aggressiveness. Interestingly, the effect was more pronounced in European Americans.

There has been long-standing debate over the role of dietary fat in promoting prostate cancer, with variations seen across nations. While mouse models suggested a possible role for high fat diets in the development of invasive prostate cancer, several prospective studies were conducted that did not find an association between the variety of dietary fat and the risk of prostate cancer. The authors of a new study, published in Prostate Cancer and Prostatic Disease, point out that previous studies that evaluated this association failed to consider the impact of the patient’s race—a majority of participants in those studies were of the white race. For their study, the authors used data from the North Carolina-Louisiana PC Project (PCaP) that followed development of prostate cancer in European Americans and African Americans.

The study enrolled 1854 patients between the ages of 40 to 79 years, who were diagnosed with prostate cancer on or after July 1, 2004. Of these, 321 had highly aggressive disease, while the remaining patients had low/intermediate aggressive disease. Information on screening, diet, and statin use was gathered via a questionnaire administered by research nurses who visited the patients at home, 3 months following their diagnosis. Information on dietary intake during the year prior to diagnosis was documented. The primary analysis studied the association between total fat-adjusted saturated fat intake and high aggressive prostate cancer using logistic regression, overall and stratified by race and statin use. Secondary analysis examined the total fat-adjusted polyunsaturated and monounsaturated fatty acids (PUFA and MUFA, respectively), trans fat, and cholesterol intake.

The study found that high total fat-adjusted saturated fat intake had a positive association with an elevated odds ratio for aggressive prostate cancer (odds ratio 1.51; 95% CI 1.10-2.06; P = .009). High total fat-adjusted cholesterol intake was found associated with aggressive prostate cancer in European Americans (ORT, 1.62; 95% CI 1.02-2.58; P = .056), but not in African Americans (OR, 0.92; 95% CI 0.60-1.42; P = .750), the authors report. Total fat-adjusted PUFA, but not MUFA, had a trend for inverse (though non-significant) association with disease aggressiveness, they report.

“Our findings suggest that limiting dietary intake of saturated fat, clearly important for cardiovascular disease prevention, may also have a role in aggressive prostate cancer prevention,” lead study author Emma Allott, PhD, assistant professor of nutrition at the University of North Carolina at Chapel Hill, told Medscape.

Study co-author Pao-Hwa Lin, PhD, associate professor of medicine, Duke University Medical Center, said, “The study supports a role of saturated fat in prostate cancer progression,” although being observational, no definitive conclusions can be drawn from their analysis.

Reference

Allott EH, Arab L, Su LJ, et al. Saturated fat intake and prostate cancer aggressiveness: results from the population-based North Carolina-Louisiana Prostate Cancer Project [published online September 6, 2016]. Prostate Cancer Prostatic Dis. doi: 10.1038/pcan.2016.39.