Cancer is when cells in the body change and grow out of control. To help you understand what happens when you have cancer, let’s look at how your body works normally. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them, and die when your body does not need them any longer.

Cancer is made up of abnormal cells that grow even though your body doesn’t need them. In most cancers, the abnormal cells grow to form a lump or mass called a tumor. If cancer cells are in the body long enough, they can grow into (invade) nearby areas. They can even spread to other parts of the body (metastasis).

Uterine sarcoma is a type of cancer that starts in the muscular wall of the uterus. (This part of the uterus is called the myometrium.) Most uterine cancers are not uterine sarcoma, they are endometrial cancers. The start in the inner lining of the uterus.

The uterus is an organ that’s part of the female reproductive system. You may know it as the womb. The uterus is usually pear-shaped and about the size of a fist. It is located in the lower belly (pelvic area), between your bladder and your rectum. Your uterus is connected to your fallopian tubes. These tubes help carry eggs from your ovaries into the uterus. The small opening that connects the uterus to your vagina is the cervix.

The uterus is made up of 3 layers:

• Endometrium. This is the inner lining.

• Myometrium. This is the middle muscle layer.

• Serosa. This is the outer smooth layer.

The uterus protects a growing baby during pregnancy. During labor, the myometrium muscle tissue helps push the baby out through the cervix. The smooth serosa makes it easy for the uterus to move in the pelvis as needed.

If uterine sarcoma spreads, it tends to first go to places near the uterus. It can spread to the cervix, vagina, ovaries, fallopian tubes, and lymph nodes. In later stages, as it grows, it can spread to the bladder, bowel, lungs, liver, or bone. 

Cancer that spreads to other parts of the body is called metastatic cancer. The process of spreading is called metastasis. Metastasis is a complex process. The cancer cells of the tumor grow into other tissues, blood vessels, and the lymph system. They then travel through the bloodstream or the lymph system to reach other parts of the body, where they can grow into new tumors.

If you have questions about uterine sarcoma, talk with your healthcare provider. Your healthcare provider can help you understand more about this cancer.