PIK3CA and breast cancer: Interestingly, although like other tumor mouse models, breast cancer mouse models with enhanced PI3K activity targeted in epithelial cells, still exhibit vascular phenotypes such that both lymphatic (LMs) and venous malformations (VeMs) and have been reported in epithelial cancers associated with GOF PIK3CA mutations [72,101], suggesting a shared genetic mechanism between breast cancers and vascular anomalies.