Effect of a Behavioral Intervention to Increase Vegetable Consumption on Cancer Progression Among Men With Early-Stage Prostate Cancer

Abstract

IMPORTANCE Guidelines endorsing vegetable-enriched diets to improve outcomes for prostate cancer survivors are based on expert opinion, preclinical studies, and observational data. OBJECTIVE To determine the effect of a behavioral intervention that increased vegetable intake on cancer progression in men with early-stage prostate cancer. DESIGN, SETTING, AND PARTICIPANTS The Men's Eating and Living (MEAL) Study (CALGB 70807 [Alliance]) was a randomized clinical trial conducted at 91 US urology and medical oncology clinics that enrolled 478 men aged 50 to 80 years with biopsy-proven prostate adenocarcinoma (International Society of Urological Pathology grade group = 1 in those <70 years and Յ2 in those Ն70 years), stage cT2a or less, and serum prostate-specific antigen (PSA) level less than 10 ng/mL. Enrollment occurred from January 2011 to August 2015; 24-month follow-up occurred from January 2013 to August 2017. INTERVENTIONS Patients were randomized to a counseling behavioral intervention by telephone promoting consumption of 7 or more daily vegetable servings (MEAL intervention; n = 237) or a control group, which received written information about diet and prostate cancer (n = 241). MAIN OUTCOMES AND MEASURES The primary outcome was time to progression; progression was defined as PSA level of 10 ng/mL or greater, PSA doubling time of less than 3 years, or upgrading (defined as increase in tumor volume or grade) on follow-up prostate biopsy. RESULTS Among 478 patients randomized (mean [SD] age, 64 [7] years; mean [SD] PSA level, 4.9 [2.1] ng/mL), 443 eligible patients (93%) were included in the primary analysis. There were 245 progression events (intervention: 124; control: 121). There were no significant differences in time to progression (unadjusted hazards ratio, 0.96 [95% CI, 0.75 to 1.24]; adjusted hazard ratio, 0.97 [95% CI, 0.76 to 1.25]). The 24-month Kaplan-Meier progression-free percentages were 43.5% [95% CI, 36.5% to 50.6%] and 41.4% [95% CI, 34.3% to 48.7%] for the intervention and control groups, respectively (difference, 2.1% [95% CI, −8.1% to 12.2%]). CONCLUSIONS AND RELEVANCE Among men with early-stage prostate cancer managed with active surveillance, a behavioral intervention that increased vegetable consumption did not significantly reduce the risk of prostate cancer progression. The findings do not support use of this intervention to decrease prostate cancer progression in this population, although the study may have been underpowered to identify a clinically important difference.

Post-Diagnostic Dietary and Lifestyle Factors and Prostate Cancer Recurrence, Progression, and Mortality

“…Recent findings from the Men’s Eating and Living (MEAL) trial warrant discussion. MEAL randomized 443 men with low-risk PC on active surveillance to receive counseling promoting consumption of ≥ 7 vegetable-fruit servings/day, including at least two servings each of cruciferous vegetables and tomatoes [ 88 ]. During the 2-year intervention, 245 events of progression were observed.…”

Dietary Factors and Supplements Influencing Prostate-Specific Antigen (PSA) Concentrations in Men with Prostate Cancer and Increased Cancer Risk: An Evidence Analysis Review Based on Randomized Controlled Trials

“…One year after the initiation of the trial, a favorable reduction was noted in the PSA concentrations of the intervention group. In the Men’s Eating and Living (MEAL) [ 211 ] study, telephone counseling promoting an increased vegetable intake for a total of two years failed to change PSA concentrations of men with biopsy-proven prostate adenocarcinoma (stage cT2a or less) and serum PSA concentrations not exceeding 10 ng/mL [ 211 ]. In parallel, time to progression (TTP), defined as PSA exceeding 10 ng/mL, did not differ between the participating groups.…”

The Impact of the COVID-19 Pandemic on Genitourinary Cancer Care: Re-envisioning the Future

“…When compared with “usual care”, the P3P intervention was associated with less decision conflict. In a randomised trial, a telephone-based intervention was better than written materials in modifying dietary behaviour [18] . Each of these studies demonstrates the added value of remote interactions.…”