PIK3CA and colorectal carcinoma: Our research found that 57.9% of CRC harbor mutations in KRAS, NRAS or BRAF. Additionally, another 17.5% of patients with wild type versions of the above genes were identified with genetic mutations in PTEN, PIK3CA and HER2. Consequently, up to 75.4% of patients might not benefit from anti-EGFR therapy.