Greater intake of a proinflammatory dietary pattern may be linked to worse overall survival in patients with stage III colon cancer who have undergone curative-intent resection. Sara K. Char, MD, a clinical fellow at Dana-Farber Cancer Institute, Boston, presented the results of a prospective cohort study within the randomized phase III CALGB/SWOG 80702 (Alliance) trial on behalf of her colleagues at the 2025 ASCO Annual Meeting.1 In addition, she added, regular physical activity may attenuate this association.
“We know that systemic inflammation in the body is implicated in both colon cancer development and in its progression,” stated Dr. Char during a press briefing on May 31, 2025, at the ASCO Annual Meeting. “And certain dietary patterns can be correlated with systemic inflammation.”
Sara K. Char, MD
Kimmie Ng, MD, MPH
Chen Yuan, ScD
Kimmie Ng, MD, MPH, Associate Chief of the Division of Gastrointestinal Oncology, and Chen Yuan, ScD, both of Dana-Farber, are co-senior authors. “This study provides additional evidence that diet may be important for improving outcomes and survival in patients with stage III colon cancer,” stated Dr. Ng in a Dana-Farber press release. “Further studies are needed to tailor specific dietary recommendations for patients with colon cancer and to understand the biological mechanisms underlying the relationship between proinflammatory diets and survival.”
Study Details
The investigators focused on an EDIP (empirical dietary inflammatory pattern) score—a tool for measuring the inflammatory potential of diets that has been validated in several large cohorts. “This score that one gets from this dietary pattern statistically correlates the intake of specific foods with plasma levels of the inflammatory markers C-reactive protein, interleukin-6, and tumor necrosis factor–alpha receptor 2,” Dr. Char noted.
This EDIP score is a weighted sum of 18 food groups: 9 proinflammatory food groups (eg, red and processed meat and refined grains) and 9 anti-inflammatory food groups (eg, certain vegetables, fruit juices, wine, coffee, tea, and beer). “A higher EDIP score corresponds to a more proinflammatory diet,” she explained.
The study cohort consisted of 1,625 patients (with a mean age of 60.9 years) with resected stage III colon cancer who were randomly assigned in a phase III trial to 3 vs 6 months of adjuvant FOLFOX (leucovorin, fluorouracil, oxaliplatin) chemotherapy and adjuvant celecoxib vs placebo. In this cohort study, the EDIP score was derived as a cumulative exposure from responses of a food-frequency questionnaire, which was completed within 6 weeks of randomization and between 14 and 16 months after randomization. To assess the potential association between the empirical dietary inflammatory pattern and disease-free and overall survival, the study investigators used Cox proportional hazards regression.
“Those who had the best overall survival outcomes were patients who engaged in higher physical activity levels and consumed less proinflammatory diets.”— SARA K. CHAR, MD
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According to the study authors, patients who were in the highest EDIP quintile (ie, had a more inflammatory diet) were younger (58.7 ± 10.8 vs 61.3 ± 9.5 years old), more likely to be female (64.0% vs 48.9%), and had a poorer Eastern Cooperative Oncology Group (ECOG) performance status (ECOG status of 1 or 2: 35.7% vs 19.4%) than did patients who were in the lowest EDIP quintile. Patients in the highest EDIP quintile also were less likely to be White (76.9% vs 92.0%) and more likely to be Black (15.2% vs 3.7%). In addition, baseline aspirin use, assigned chemotherapy (3 months vs 6 months), and assigned pharmacotherapy (celecoxib vs placebo) were not found to be significantly different across the EDIP quintiles.
Key Results
In terms of overall survival outcomes, patients in the highest EDIP quintile had significantly worse overall survival (multivariable hazard ratio [HR] = 1.87, 95% confidence interval [CI] = 1.26–2.77, P trend = .01) than did patients in the lowest EDIP quintile. “Numerically, there is a trend toward worse disease-free survival with more proinflammatory diets, with a hazard ratio of 1.36,” Dr. Char added. “However, in our multivariable adjusted model, this was not statistically significant.” As for overall survival, “patients with the most proinflammatory diets (top 20%) had an 87% higher risk of death than those with the least proinflammatory diets (bottom 20%),” she said. “And the median overall survival in the highest EDIP quintile was 7.7 years, whereas it was not reached in those in the lowest EDIP quintile.”
Furthermore, when the investigators analyzed the findings in the celecoxib and placebo treatment arms (P interaction = .54), the association between a higher EDIP and overall survival was found to be consistent. The relationship between EDIP and overall survival was not found to differ significantly based on aspirin use; the hazard ratios were 1.60 (95% CI = 0.71–3.60) among aspirin users and 2.01 (95% CI = 1.27–3.16) among nonusers (P interaction = .06).
Finally, the investigators reported that diet and physical activity jointly seemed to influence overall survival. Specifically, those in the lower EDIP quintiles (80% of the study population) who had higher physical activity (≥ 9 metabolic equivalent hours/week) experienced the best overall survival (HR = 0.37, 95% CI = 0.25–0.53) when compared with patients in the highest EDIP quintile (20% of the study population) who had lower physical activity (< 9 metabolic equivalent hours/week; P interaction < .001). “Those who had the best overall survival outcomes were patients who engaged in higher physical activity levels and consumed less proinflammatory diets,” Dr. Char explained.
Julie R. Gralow, MD, FACP, FASCO
Julie R. Gralow, MD, FACP, FASCO, ASCO Chief Medical Officer and Executive Vice President, shared a few comments about the clinical significance of this research. “This promising observational study suggests a powerful synergy: patients with stage III colon cancer who embraced anti-inflammatory foods and exercised regularly showed the best overall survival compared to those with inflammatory diets and limited exercise. We as physicians need to be essentially prescribing a healthy diet and exercise.”
DISCLOSURE: The study was funded by the National Institutes of Health, Pfizer, and the Project P Fund. Dr. Char reported that she has served as a consultant or advisor to Goodpath. For full disclosures of all other authors from the CALGB/SWOG 80702 (Alliance) study, visit coi.asco.org. Dr. Gralow reported no conflicts of interest.
REFERENCE
1. Char SK, Shi Q, Zemla T, et al: Association between empirical dietary inflammatory pattern and survival in patients with stage III colon cancer: Findings from CALGB/SWOG 80702 (Alliance). 2025 ASCO Annual Meeting. Abstract LBA3509. Presented May 31, 2025.
