Dietary factors have been associated with the risk of developing colon cancer.
However, the influence of diet on patients with established disease is unknown.
Dr Jeffrey Meyerhardt and colleagues from Massachusetts, USA determined the association of dietary patterns with cancer recurrences and mortality of colon cancer survivors.
The team undertook a prospective observational study of 1009 patients with stage III colon cancer.
The patients were enrolled in a randomized adjuvant chemotherapy trial between 1999 and 2001.
|324 patients had cancer recurrence during a 5-year follow-up|
|Journal of the American Medical Association|
Patients reported on dietary intake using a semiquantitative food frequency questionnaire during and 6 months after adjuvant chemotherapy.
The team identified 2 major dietary patterns, prudent and Western, by factor analysis.
The team found that the prudent pattern was characterized by high intakes of fruits and vegetables, poultry, and fish.
The Western pattern was characterized by high intakes of meat, fat, refined grains, and dessert.
Patients were followed up for cancer recurrence or death.
The team identified, disease-free survival, recurrence-free survival, and overall survival by dietary pattern.
The researchers found that during a median follow-up of 5 years for the overall cohort, 324 patients had cancer recurrence.
The team reported that 223 patients died with cancer recurrence, and 28 died without documented cancer recurrence.
The team showed that a higher intake of a Western dietary pattern after cancer diagnosis was associated with a significantly worse disease-free survival.
Compared with patients in the lowest quintile of Western dietary pattern, those in the highest quintile experienced an adjusted hazard ratio for disease-free survival of 3.
The team found the Western dietary pattern was associated with a similar detriment in recurrence-free survival, with overall survival.
The reduction in disease-free survival with a Western dietary pattern was not significantly modified by sex, age, nodal stage, body mass index, physical activity level, baseline performance status, or treatment group.
The team noted that in contrast, the prudent dietary pattern was not significantly associated with cancer recurrence or mortality.
Dr Meyerhardt's team concluded, "Higher intake of a Western dietary pattern may be associated with a higher risk of recurrence and mortality among patients with stage III colon cancer treated with surgery and adjuvant chemotherapy."
"Further studies are needed to delineate which components of such a diet show the strongest association."