stage I endometrial cancer (... EN-doh-MEE-tree-ul KAN-ser)
Cancer is found in the uterus only. Stage I is divided into stages IA and IB, based on how far the cancer has spread. In stage IA, cancer is in the endometrium only or less than halfway through the myometrium (muscle layer of the uterus). In stage IB, cancer has spread halfway or more into the myometrium.