stage I endometrioid carcinoma (MONDO_0004961, a Monarch Disease Ontology id) can be described as follows. Endometrial cancer is a cancer that arises from the endometrium (the lining of the uterus or womb).It is the result of the abnormal growth of cells that have the ability to invade or spread to other parts of the body. The first sign is most often vaginal bleeding not associated with a menstrual period. Other symptoms include pain with urination or sexual intercourse, or pelvic pain. Endometrial cancer occurs most commonly after menopause. In stage I, the cancer is only growing in the body of the uterus. It may also be growing into the glands of the cervix, but is not growing into the supporting connective tissue of the cervix.