Our study was looking at inflammation and outcomes in stage III colon cancer. We know that inflammation is important both for colon cancer development and progression, so we were curious how inflammation related to diet would impact survival outcomes, specifically in patients with stage III colon cancer.

We used a validated tool for measuring the inflammatory potential of a diet called EDIP, or Empirical Dietary Inflammatory Pattern, and by applying this to patients’ self-reported dietary data we were able to calculate an EDIP score, where higher scores correspond with more inflammatory diets.

We found, in our secondary analysis of a phase III clinical trial that patients who consumed more pro-inflammatory diets had worse overall survival compared to those who consumed the least inflammatory diets, and that physical activity and diet together could impact survival. We saw the best survival outcomes in those who had higher levels of physical activity and consumed less inflammatory diets, compared to those who had less physical activity and consumed more pro-inflammatory diets.

What was the methodology and what did you find?

The methodology of our study, this was a prospective cohort study and a secondary analysis of a phase III clinical trial called CALGB/SWOG 80702. We used a Cox proportional hazards model to model the association between the exposure, which was inflammatory diet, and the outcomes with a primary outcome of disease free survival and a secondary outcome of overall survival.

For disease free survival we did not find a statistically significant association between inflammatory diet and disease free survival in a multivariable adjusted hazard ratio, but for overall survival we did see a statistically significant difference when modelling EDIP against overall survival.

What are the clinical implications of these findings?

I think that this study adds to the body of literature that we have that diet may prolong survival in stage III colon cancer. Our study results looked at an inflammatory dietary pattern but they are not a dietary recommendation, and so we need further studies to be able to tailor our findings into dietary recommendations for patients.

I would say that we are encouraged by the results that show that there is a way that we potentially could look at diet as a way to improve survival in stage III colon cancer, but based on our study results alone I would not recommend dietary modulation. We need further studies for that.