Morales-Oyarvide V, et al. - Researchers assessed how outcomes of stage III colon cancer patients are impacted by postdiagnosis dietary insulin load and dietary insulin index. An increased risk of recurrence and mortality was observed in patients with resected stage III colon cancer who consumed a high-insulinogenic diet. Based on the results, dietary management following resection of colon cancer are important.

Methods

• Researchers performed this prospective observational study including 1,023 patients with resected stage III colon cancer enrolled in an adjuvant chemotherapy trial that reported dietary intake halfway through and six months after chemotherapy.
• They used Cox proportional hazards regression adjusted for potential confounders to assess the association of dietary insulin load and dietary insulin index with cancer recurrence and survival; statistical tests were two-sided.

Results

• They found high dietary insulin load was significantly related to worse disease-free survival (DFS), when comparing the highest vs lowest quintile (adjusted hazard ratio [HR] = 2.77, 95% confidence interval [CI] = 1.90 to 4.02, P_trend < .001).
• They also observed an association of high dietary insulin index with worse DFS (highest vs lowest quintile, HR = 1.75, 95% CI = 1.22 to 2.51, P_trend=.01).
• Findings revealed that obese patients had the strongest link between higher dietary insulin load and worse DFS; the association between higher dietary insulin load and worse DFS differed by body mass (HR = 3.66, 95% CI = 1.88 to 7.12, P_interaction=.04).
• Based on the mutation status of KRAS, BRAF, PIK3CA, TP53, or microsatellite instability, no difference was observed regarding the impact of dietary insulin load on cancer outcomes.