Consuming an anti-inflammatory diet could improve posttreatment survival among patients with colorectal cancer compared with following a proinflammatory diet, according to new findings presented by Char et al at the 2025 ASCO Annual Meeting (Abstract LBA3509). The findings suggested that engaging in higher levels of physical activity could help amplify the positive influence on cancer survival.
Background
Each year in the United States, about 150,000 patients are diagnosed with colorectal cancer. Globally, colorectal cancer is the third most diagnosed cancer type and the second-leading cause of cancer-related mortality. The median 5-year survival among patients with stage III colorectal cancer is approximately 80%; however, 25% to 35% of patients experience cancer recurrence.
Previous research showed that systemic inflammation can increase the risk of colorectal cancer development and progression as well as that the use of anti-inflammatory drugs can decrease the risk of cancer recurrence in certain patients with stage III colorectal cancer.
“One of the most common questions that patients ask is what they should do after treatment to maximally reduce their risk of cancer recurrence and improve survival,” noted lead study author Sara Char, MD, a clinical fellow in Hematology and Oncology at Dana-Farber Cancer Institute. “These findings add to the published literature about the importance of dietary patterns and physical activity in outcomes of patients with colorectal cancer,” she added.
A proinflammatory diet includes higher amounts of red meat, processed meats, refined grains, and sugar-sweetened beverages; whereas an anti-inflammatory diet frequently includes coffee, tea, and a variety of vegetables like leafy greens.
“A proinflammatory diet would be enriched with these proinflammatory food groups, whereas a less inflammatory diet might be enriched with more of the anti-inflammatory food groups,” explained Dr. Char.
Study Methods and Results
In 2010, researchers initiated the CALGB/SWOG 80702 (Alliance) trial, which aimed to reduce the risk of cancer recurrence among patients with stage III colorectal cancer. Those who participated in the trial underwent surgery followed by either 3 or 6 months of chemotherapy, with or without the anti-inflammatory drug celecoxib. They also had the option to complete dietary and lifestyle questionnaires.
Among the 2,526 patients enrolled in the trial, 1,625 were eligible for the new phase III trial following completion of food frequency and physical activity questionnaires. The researchers then calculated a validated empirical dietary inflammatory pattern (EDIP) score to approximate how inflammatory certain diets were for each patient.
After ranking the patients’ diets from most to least proinflammatory, they then assessed overall survival outcomes.
They found that patients consuming the most proinflammatory diets (in the top 20% of the ranking) had an 87% higher risk of death than those consuming the least proinflammatory diets (in the bottom 20%).
In addition, the researchers collected information regarding the patients’ physical activity, evaluating the average weekly intensity of activities. Patients considered to have a high level of physical activity reported the equivalent of regularly walking at a 2 to 3 mph pace for 1 hour approximately three times or more each week. The researchers revealed that the patients who consumed more anti-inflammatory diets and engaged in higher levels of physical activity had the greatest overall survival outcomes, with a 63% lower risk of mortality compared with patients who consumed the most proinflammatory diets and engaged in lower levels of physical activity.
Because patients in the trial were randomly assigned to receive chemotherapy with or without celecoxib, the researchers investigated the influence of the drug on their analysis. They found that the use of celecoxib did not have a significant influence on the relationship between diet and cancer survival.
Conclusions
The findings added to research indicating that dietary choices may influence cancer outcomes following treatment.
“This study provides additional evidence that diet may be important for improving outcomes and survival in patients with stage III [colorectal] cancer,” emphasized senior study author Kimmie Ng, MD, MPH, Associate Chief of the Division of Gastrointestinal Oncology at Dana-Farber Cancer Institute. “Further studies are needed to tailor specific dietary recommendations for patients with [colorectal] cancer and to understand the biological mechanisms underlying the relationship between proinflammatory diets and survival,” she continued.
The researchers plan to conduct further studies focused on the biological effects of diet and lifestyle on colorectal cancer outcomes, including on metastatic disease and those diagnosed younger than 50 years.
Disclosure: The research in this study was funded by the National Institutes of Health, the Project P Fund, and the Alliance for Clinical Trials in Oncology. For full disclosures of the study authors, visit meetings.asco.org.
