PIK3CA and breast carcinoma: Oncogenomic studies have demonstrated frequent activation of PI3K–AKT–mTOR signaling in the invasive lobular carcinoma (ILC) histological subtype of breast cancers, suggesting this pathway to be a particularly promising therapeutic target for ILC (Ciriello et al., 2015; Curtis et al., 2012; Michaut et al., 2016).