Stage IA: tumor is limited to less than half the myometrium Stage IB: invasion of more than half the myometrium Stage II: cervical stromal invasion Stage IIIA: tumor invades serosa or adnexa Stage IIIB: vaginal or parametrial metastasis Stage IIIC1: metastasis to pelvic lymph nodes Stage IIIC2: metastasis to para-aortic lymph nodes Stage IVA: invasion of the bladder or bowel Stage IVB: distant metastasis, including intra-abdominal or inguinal lymph nodes