Uterine cancer

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What is uterine cancer?

Uterine cancer is the most common cancer of the female reproductive system. It is a malignant tumour that starts in the cells of the uterus. Malignant means that it can invade, or grow into, and destroy nearby tissue. It can also spread, or metastasize, to other parts of the body.

The uterus, or womb, is part of a woman’s reproductive system. The uterus is the hollow, muscular, pear-shaped organ where a fetus develops and grows during pregnancy. The lining of the uterus is called the endometrium. It is made up of tissue with many glands. The lower part of the uterus is called the cervix. The cervix leads into the vagina.

Cells in the uterus sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous, or benign, conditions such as endometriosis. They can also lead to non-cancerous tumours such as uterine fibroids.

Changes to cells in the uterus can also cause precancerous conditions. This means that the abnormal cells are not yet cancer, but there is a chance that they may become cancer if they aren’t treated. The most common precancerous condition of the uterus is atypical endometrial hyperplasia.

In some cases, changes to cells in the uterus can cause cancer. There are 2 main types of uterine cancer. Most uterine cancers are endometrial carcinoma, which starts from cells in the lining of the uterus (called the endometrium). Uterine sarcoma develops in the supporting tissues of the uterus, including muscle, fat, bone and fibrous tissue (material that forms ligaments and tendons). A third type of cancer called carcinosarcoma sometimes develops in the uterus. It has features of both carcinomascarcinomasA type of cancer that starts in epithelial tissues (a layer of cells that lines the body’s hollow organs and glands and makes up the outer layer of the skin). and sarcomassarcomasA type of cancer that starts in connective tissues (tissue that surrounds and supports various organs in the body)..

Rare types of uterine cancer can also develop, including gestational trophoblastic disease (GTD). Find out more about gestational trophoblastic disease.

Diagram of the female reproductive system


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