PIK3CA and cervical squamous cell carcinoma: Somatic mutation analysis showed that the most frequent mutation genes were PIK3CA, FBXW7, and TP53 (Fig. 3d), which were consistent with the previous study from the TCGA cervical squamous cell carcinoma and endocervical adenocarcinoma (TCGA-CESC).18 A few mutations were observed exclusively in the non-pCR cohort, including the STK11 mutation.