PTEN and squamous cell carcinoma: Almost half of the patients with metastatic or recurrent cervical carcinoma, especially those with squamous cell carcinoma, presented with PIK3CA mutation and/or PTEN loss/mutation, and this proportion was significantly higher in patients with advanced solid tumors (48% versus 22%, p = 0.002), suggesting that the activated PI3K/AKT/mTOR pathway is a driving mechanism for the survival of cervical carcinoma cells.