DPP4 and cancer: In a multi-center retrospective study of diabetic patients with advanced colorectal or airway (lung, head, and neck) cancer, only 23.7% of patients on DPP4 inhibitor and metformin exhibited cancer progression compared to 50.9% of controls on metformin and a sulfonylurea (odds ratio: 0.30; 95% CI: 0.11-0.81; p = 0.010) [3].