Cancer in the uterus, a pear-shaped organ where the fetus develops, usually starts in the inner lining called the endometrium. This type of cancer, endometrial cancer, is typically found in women 55 years and older. Sarcoma, a more rare form of uterine cancer, develops in the outer muscle layer of the uterus, known as the myometrium. Only about 2 to 5 percent of uterine cancers are sarcomas, but they are typically more aggressive and can spread quickly.
Uterine cancer is the most common gynecologic cancer. About 52,000 new cases are diagnosed annually in the U.S.
The most common warning sign of uterine cancer is post-menopausal bleeding, and, in younger women, bleeding not associated with menstrual periods. Other more rare symptoms include a mass in the vagina, pain or feeling of fullness in the abdomen and frequent urination. Uterine cancer may also cause a non-bloody vaginal discharge.
The exact cause of uterine cancer is still unknown but researchers have found that estrogen plays a role. Many endometrial cells contain estrogen receptors on their surfaces, and interaction between receptors and estrogen leads to increased growth of the endometrium. This buildup can become increasingly abnormal until it develops into cancer.
There are no screening tests to find uterine cancer early.
If uterine cancer is suspected, an endometrial biopsy is typically performed in a physician's office. This procedure involves taking out a small amount of endometrium, the inner lining of the uterus. A hysteroscopy may also be used to test for uterine cancer, which requires filling the uterus with saline and looking into it for abnormal cells or growths such as polyps. Patients are usually awake for both procedures, though a local anesthesia may be used.
Surgery, radiation, chemotherapy and hormonal therapy can all be used to treat uterine cancer.
Surgery is used most often. A hysterectomy is the standard procedure.
Radiation therapy is also used frequently. Depending on a number of factors, radiation is either delivered externally or internally, when radioactive materials are placed inside the body.
Progesterone-like drugs are typically used for hormonal therapy. They slow the growth of endometrial cancer cells by working to prevent estrogen in the body from stimulating cancer cell growth. They are usually prescribed for women with advanced or recurrent uterine cancer.