Uterine cancer has four stages. Stage 1 or stage 2 uterine cancer is cancer that is confined to the uterus, whereas stage 3 and 4 uterine cancers have already spread to other parts of the body, according to the National Cancer Institute.
Stage 1A uterine cancer affects the endometrium, or womb lining, and has spread no more than halfway into the myometrium, which is the muscular layer of the uterus. Stage 1B uterine cancer has spread more than halfway through this muscular layer, notes the National Cancer Institute. Stage 2 uterine cancers also affect the connective tissue of the cervix, but have not spread to other parts of the body.
Stage 3 uterine cancer affects other parts of the pelvis, explains the National Cancer Institute. Stage 3A uterine cancer affects the ovaries or fallopian tubes as well as the outer layer of the uterus. Stage 3B cancers also affect the vagina or the tissues surrounding the uterus. Stage 3C cancers have spread to the pelvic lymph nodes. From here, cancer cells spread to other parts of the body via the lymphatic system. This leads to the patient developing stage 4 cancer, which affects parts of the body beyond the pelvis. Stage 4A uterine cancer affects the bladder and bowel, where stage 4B cancer affects other parts of the abdomen.