PIK3CA and colorectal carcinoma: In this study we also observed that PIK3CA codon 545 substitutions account for 9.8% of PIK3CA mutations in CRC [49] and, since the carcinoma carrying the PIK3CA p.Glu545Asp mutation did not present mutations in either KRAS or BRAF, it is conceivable that this mutation confers some selective advantage.