Uterine cancer, the most common cancer of a woman's reproductive system, accounts for 6 percent of all female cancers in the United States, according to the National Cancer Institute. The uterus is a hollow organ that sits in the pelvis and supports the growth of a baby during pregnancy. Cancer of the uterus most often begins in the endometrium, the inner layer of the uterine wall. Uterine cancer is staged based on how much the cancer has grown and helps to determine the best treatment strategy.
Stage 0
The American Cancer Society describes this stage as carcinoma in-situ. The cancer cells have not spread beyond the surface of the endometrial (inner) layer of the uterus. It has not yet spread to the other layers of the uterus. The prognosis of stage 0 uterine cancer is quite good, with a five-year survival rate of 90 percent.
Stage I
The National Cancer Institute reports that in stage I, the cancer is present only in the body of the uterus and has not spread to the cone-shaped cervix at the end of the uterus. Merck Manuals, an online medical library, adds that uterine cancer in this stage may have grown from the endometrium into the myometrium (the outer muscle layer of the uterus) but not beyond. The American Cancer Society notes that the five-year survival rate of those diagnosed with stage I uterine cancer is between 75 and 88 percent.
Stage II
The American Cancer Society reports that stage II uterine cancer means that the cancerous cells have spread into the cervix. And even though it has spread from the body of the uterus, the five-year survival rate is approximately 69 percent. Merck Manuals adds that the cancer may have spread to the cervical tissue itself, the cervical glands or the cervical stroma, the supporting connective tissue attached to the cervix.
Stage III
Stage III uterine cancer means the cancer has spread beyond the uterus but still remains in the pelvis, according to the National Cancer Institute. The cancer may have spread to lymph nodes in the pelvis but not to lymph nodes elsewhere in the body. Additionally, the cancer also has not spread to the rectum or the bladder. The American Cancer Society adds that the cancer may have spread to the fallopian tubes, the ovaries or the vagina. Uterine cancer in this stage has a five-year survival rate between 47 and 58 percent.
Stage IV
Stage IV is the most advanced stage of uterine cancer. In stage IV cancer of the uterus, the cancer is growing inside the bladder and/or the rectum and has invaded other organs of the body, such as the intestines, bones or lungs; it may also have spread to lymph nodes outside the pelvis. When uterine cancer has advanced to stage IV, it becomes difficult to treat and has a five-year survival rate of less than 20 percent.
