PIK3CA and cancer: Compared with TCGA datasets, our cohort constituted comparable levels of major cancer-driver genes in respective cancer types, including somatic mutations of TP53 in EOCs, PIK3CA and PTEN in cervical cancers, and PTEN, PIK3CA, ARID1A, and CTNNB1 in uterine corpus endometrial carcinomas (Additional file 1: Figure S2).