PIK3CA and breast cancer: Following targeted next generation sequencing genotyping in 1766 FFPE DNA samples, PIK3CA and TP53 gene mutations were found in 25.9% and 21.5% of the patients, respectively, percentages that are remarkably similar to those reported for breast cancer in the Catalog of Somatic Mutations in Cancer (COSMIC, 26% and 23%, respectively) [35].