Endometrial cancer (EC) is one of the most common gynecological neoplasms, being the second in incidence and third in mortality in Mexico. Recent studies show that EC molecular classification (Cancer Genome Atlas Research Network, 2013) serves to establish a more accurate prognosis in these patients and regulate therapeutic behavior in a personalized manner. However, there are no studies on EC molecular classification in Mexican women or its impact on prognosis and the possible modification of targeted treatment. The investigators will determine the molecular classification in EC by next-generation sequencing (NGS) to detect TP53 and POLE somatic mutations, and immunohistochemical detection of microsatellite instability (MSH2, MLH1, PMS1, PMS2, MSH6, and MSH3) in a cohort of patients with endometrioid-type EC, endometrioid subtype, attended at the Instituto Nacional de Cancerología - Mexico (INCan) and determine its impact on clinical prognosis.