Western Diet and Recurrence of Colon Cancer

Dietary factors are associated with the risk for developing several cancers, including colon and breast, but the influence of diet on already established cancers is unclear. In a prospective multisite trial of adjuvant therapy in patients with stage III colon cancer who were enrolled within 2 months of the initial surgical resection, investigators assessed dietary patterns of 1009 patients during and roughly 6 months after chemotherapy. Intake frequency and quantity were assessed for 131 foods and supplements. Factor analysis identified two major dietary patterns: a Western diet (high intake of refined grains, red meat, high-fat dairy products, French fries, and desserts); and a “prudent” diet (high intake of fruits, vegetables, poultry, and fish).

During roughly 5 years of follow-up, colon cancer recurred in 324 patients; 223 patients died with recurrence. No level of compliance with a prudent diet was associated with recurrence. However, in analyses adjusted for a wide range of clinical and demographic factors, patients with the highest level of a Western dietary pattern had significantly worse disease-free survival (hazard ratio for recurrence or death, 3.25) than patients with the lowest level of a Western dietary pattern. A similar magnitude of risk was found for recurrence-free survival (HR, 2.85) and overall survival (HR, 2.32).