Given the established predictive and/or prognostic role of somatic mutations in key oncogenes (RAS, TP53, BRAF, PIK3CA, SMAD4) and microsatellite instability (MSI) status in colorectal cancer, we aimed to investigate the clinical value of the same markers in LARC patients by systematically reviewing the published literature and performing a quantitative analysis of the data. The gene discussed is PIK3CA; the disease is colorectal cancer.