The three ways that cancer spreads in the body are:
- Through tissue. Cancer invades the surrounding normal tissue.
- Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
The following stages are used for uterine sarcoma:
In stage I, cancer is found in the uterus only. Stage I is divided into stages IA and IB, based on how far the cancer has spread.
- Stage IA: Cancer is in the endometrium only or less than halfway through the myometrium (muscle layer of the uterus).
- Stage IB: Cancer has spread halfway or more into the myometrium.
In stage II, cancer has spread into connective tissue of the cervix, but has not spread outside the uterus.
In stage III, cancer has spread beyond the uterus and cervix, but has not spread beyond the pelvis. Stage III is divided into stages IIIA, IIIB, and IIIC, based on how far the cancer has spread within the pelvis.
- Stage IIIA: Cancer has spread to the outer layer of the uterus and/or to the fallopian tubes, ovaries, and ligaments of the uterus.
- Stage IIIB: Cancer has spread to the vagina or to the parametrium (connective tissue and fat around the uterus).
- Stage IIIC: Cancer has spread to lymph nodes in the pelvis and/or around the aorta (largest artery in the body, which carries blood away from the heart).
In stage IV, cancer has spread beyond the pelvis. Stage IV is divided into stages IVA and IVB, based on how far the cancer has spread.
- Stage IVA: Cancer has spread to the bladder and/or bowel wall.
- Stage IVB: Cancer has spread to other parts of the body beyond the pelvis, including the abdomen and/or lymph nodes in the groin.