Quality of Diet May Reduce Chances of Prostate Cancer Progression During Active Surveillance: Study - Video

A research team led by Johns Hopkins Medicine provides scientific evidence that a healthy diet may reduce the chance of low risk prostate cancer progressing to a more aggressive state in men undergoing active surveillance — a clinical option in which men with lower risk cancer are carefully monitored for progression in lieu of treatments that could have undesired side effects or complications. The findings are reported in the journal

JAMA Oncology.

“Many men diagnosed with low grade prostate cancer are interested in changes they can make to reduce the risk of their tumor becoming more aggressive, and the role of diet and nutrition is one of the most commonly asked questions,” says study co-senior author Bruce Trock, Ph.D., a professor of urology, epidemiology and oncology at the Johns Hopkins University School of Medicine, and director of the Brady Urological Institute’s epidemiology division. “These men are motivated to make changes that may improve their prognosis, which is why we began collecting data on their diets, lifestyles and exposures 20 years ago. Hopefully, these latest findings will enable us to develop some concrete steps they can take to reduce the risk of cancer progression.”

In the newly published study, the researchers prospectively evaluated the histories of 886 men diagnosed with grade group 1 prostate cancer from January 2005 to February 2017, all of whom were in the Johns Hopkins Medicine active surveillance program and whom, at the time of enrollment, completed a validated food frequency survey — the Block 1998 Food Frequency Questionnaire — regarding their usual dietary patterns. Of the participants, 55 were Black, 803 were white and 28 identified as other races and ethnicities.

Based on their responses to the questionnaire, a Healthy Eating Index (HEI) score was calculated for each patient. The Healthy Eating Index ranges from 0 to 100.

Zhuo Tony Su, M.D., a fifth-year resident at the Brady Urological Institute and the Johns Hopkins University School of Medicine says the researchers also evaluated the patients using an energy-adjusted Healthy Eating Index (E-HEI) score that takes into account a person’s daily caloric intake.

Along with those two metrics, Su says, the researchers calculated scores for each study participant using the Dietary Inflammatory Index (DII) and the energy-adjusted Dietary Inflammatory Index (E-DII).

“The Dietary Inflammatory Index and energy-adjusted Dietary Inflammatory Index scores assess the inflammatory or anti-inflammatory potential of any diet, so higher scores indicate a diet that may cause more inflammation, which in turn, may contribute to the development and progression of prostate cancer,” says Su. “We evaluated whether higher inflammatory potential was associated with increased risk of grade reclassification.”

By a follow-up assessment at 6.5 years after diagnosis, 187 men (21%) had been reclassified as grade group 2 or greater, of whom 55 (6%) had extreme grade reclassification to grade group 3 or greater.

“When our team looked at the Healthy Eating Index and energy-adjusted Healthy Eating Index scores in relation to the grade reclassification rates, we found a statistically significant inverse association between adherence to a high quality diet — as indicated by Healthy Eating Index and energy-adjusted Healthy Eating Index scores — and the risk of grade reclassification during active surveillance,” says Trock. “In other words, the higher the Healthy Eating Index and energy-adjusted Healthy Eating Index scores, the more reduced the risk that a low grade prostate cancer had progressed to a higher grade disease that mandated curative treatment.”

Pavlovich says for patients adhering to a high quality diet, every increase of 12.5 points in the Healthy Eating Index score was associated with an approximately 15% reduction in reclassification to grade group 2 or greater, and a 30% reduction in reclassification to grade group 3 or greater.

The researchers say their findings also indicate that lower inflammation potential is among several possible risk lowering mechanisms as a result of a higher quality diet.

Reference: Su ZT, Mamawala M, Landis PK, et al. Diet Quality, Dietary Inflammatory Potential, and Risk of Prostate Cancer Grade Reclassification. JAMA Oncol. Published online October 17, 2024. doi:10.1001/jamaoncol.2024.4406