Any measurement in which the number of individuals in a study population that display endometrial adenocarcinomas at a point in time or develop endometrial adenocarcinomas within a determined period of time are compared to the total number of individuals in the study population. Often expressed as a percentage but could be expressed as a ratio. An endometrial adenocarcinoma is an abnormal and malignant growth of the epithelial cells of the mucous membrane lining the uterus that results from uncontrolled, progressive multiplication of cells, serves no physiological function, and forms or appears to form glandular structures.