Plant-based diets linked to lower risk of prostate cancer progression and recurrence

Patients with prostate cancer whose diets included the highest amounts of plants had a lower risk of disease progression and recurrence,according to findings shared during the 2023 ASCO Genitourinary Cancers Symposium.^1,2

Plant-based diets were associated with improved outcomes, as the group of patients with the highest consumption of plant-based foods had a 52% lower risk of disease progression compared with the group of patients with diets that included the lowest amounts of plants.

“While not all diets are equal in terms of modifiable risk factors for prostate cancer progression, we hope these results guide people at risk to make better, more healthful choices across their entire diet,” Vivian Liu, Clinical Research Coordinator, Osher Center for Integrative Health, University of California, San Francisco, and lead study author, stated in a press release.¹

“We’ve known that diets that include vegetables, fruits, legumes, and whole grains are associated with numerous health benefits, including a reduction in diabetes, cardiovascular disease, and overall mortality. We can now add benefits in reducing prostate cancer progression to that list,” added Liu.

The study included 2038 patients with prostate cancer who were enrolled in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) study. The poster shared at the meeting showed that across all 2038 patients, the median age at baseline was 64 years (IQR, 59-70), 95% were White, the median BMI was 27 (IQR, 25-30), the median PSA was 5.6 (IQR, 4.4-7.8), and 5% were current smokers.

The range of Gleason Grades was <7 (68%), 7 exactly (26%), and >7 (6%). Fifty-eight percent of patients had stage T1 disease and 42% had stage T2. Primary treatments were as follows: radical prostatectomy (63%), active surveillance/watchful waiting (6%), radiation therapy (22%), hormone therapy (5%), and other (4%).

Study participants completed questionnaires detailing their quantity and frequency of consumption of about 140 food and beverage items. Through statistical analysis using theMultivariate Cox model, the investigators assessed/adjusted for any factors that might affect their examination of the relationship between plant-based diets and risk of prostate-cancer progression.

Over a median follow-up of 7.4 years, 10% of the study population (204 patients) had disease progression. Plant-based diets were associated with improved outcomes, as the group of patients with the highest consumption of plant-based foods had a 52% lower risk of disease progression compared with the group of patients with diets that included the lowest amounts of plants (HR, 0.48; p-trend <.001). The risk of recurrence was also 53% lower in the highest vs lowest plant consumption groups (HR, 0.47; p-trend <.001).

According to the authors, these associations “did not vary by the participants’ age, walking pace, grade at diagnosis, or cancer stage at diagnosis.”

“The risk of disease progression is one of many pivotal concerns for people with prostate cancer, as well as their family, caregivers, and physicians. These findings may directly inform clinical care, such as providing diet recommendations for managing health, and potentially offer other positive health benefits for preventing numerous chronic diseases,” Bradley Alexander McGregor, MD, ASCO expert in genitourinary cancers, stated in the press release.¹

The investigators reported that the next steps with their research will involve assessing the potential relationship between plant-based diets and prostate cancer–specific mortality. They also plan to analyze the relation between plant-based dietary measures and prostate cancer–specific quality of life.

References

1. Diet Higher in Plants Associated With Lower Risk of Prostate Cancer Progression and Recurrence. Published online February 13, 2023. Accessed March 7, 2023. https://bit.ly/3L5ZRcI

2. Liu VN, Van Blarigan EL, Zhang L, et al. Associations between plant-based diets and risk of disease progression in men with prostate cancer. J Clin Oncol 41, 2023 (suppl 6; abstr 392). doi: 10.1200/JCO.2023.41.6_suppl.392