DPP4 and colorectal carcinoma: In a surveillance epidemiology and endpoint research-medicare database study, the combination use of metformin with DPP4 inhibitors further promoted the survival advantage of CRC patients with hazard ratio (HR) of 0.83 and CI of 0.77–0.90 (P < 0.0001) as compared to the use DPP4 inhibitors alone (HR:0.89; CI: 0.82–0.97, P = 0.007) [85].