In the current work, we have reviewed the molecular determinants of RT sensitivity in EC, which include the status of the cancer survival pathways phosphatidylinositol 3-kinase (PI3K)/PTEN/protein kinase B (AKT)/mammalian target of rapamycin (mTOR), nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathway; oncoproteins such as tyrosine kinase receptors and growth hormone; proteins involved in DNA repair mechanisms and the immune system. This evidence concerns the gene PTEN and cancer.