In the present study, we aimed to evaluate KRAS, NRAS, BRAF and PIK3CA mutations using both reverse transcriptase-polymerase chain reaction (RT-PCR) and Sanger sequencing in 1,110 samples from Chinese patients with CRC and to determine the frequencies of these mutations and the relationships between these mutations and clinicopathological parameters. Here, KRAS is linked to colorectal carcinoma.