Key Points for This Section

Endometrial cancer is a disease in which malignant (cancer) cells form in the tissues of the endometrium. Taking tamoxifen for breast cancer or taking estrogen alone (without progesterone) can affect the risk of developing endometrial cancer. Possible signs of endometrial cancer include unusual vaginal discharge or pain in the pelvis. Tests that examine the endometrium are used to detect (find) and diagnose endometrial cancer. Certain factors affect prognosis (chance of recovery) and treatment options.

Endometrial cancer is a disease in which malignant (cancer) cells form in the tissues of the endometrium.

The endometrium is the lining of the uterus, a hollow, muscular organ in a woman’s pelvis. The uterus is where a fetus grows. In most nonpregnant women, the uterus is about 3 inches long. The lower, narrow end of the uterus is the cervix, which leads to the vagina.

Cancer of the endometrium is different from cancer of the muscle of the uterus, which is called sarcoma of the uterus. Refer to the PDQ summary on Uterine Sarcoma Treatment ¹ for more information.

Taking tamoxifen for breast cancer or taking estrogen alone (without progesterone) can affect the risk of developing endometrial cancer.

Endometrial cancer may develop in breast cancer patients who have been treated with tamoxifen. A patient taking this drug should have a pelvic exam every year and report any vaginal bleeding (other than menstrual bleeding) as soon as possible. Women taking estrogen (a hormone that can affect the growth of some cancers) alone have an increased risk of developing endometrial cancer. Taking estrogen in combination with progesterone (another hormone) does not increase a woman’s risk of this cancer.

Possible signs of endometrial cancer include unusual vaginal discharge or pain in the pelvis.

These and other symptoms may be caused by endometrial cancer. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

• Bleeding or discharge not related to menstruation (periods).
• Difficult or painful urination.
• Pain during sexual intercourse.
• Pain in the pelvic area.

Tests that examine the endometrium are used to detect (find) and diagnose endometrial cancer.

Because endometrial cancer begins inside the uterus, it does not usually show up in the results of a Pap test. For this reason, a sample of endometrial tissue must be removed and examined under a microscope to look for cancer cells. One of the following procedures may be used:

• Endometrial biopsy: The removal of tissue from the endometrium (inner lining of the uterus) by inserting a thin, flexible tube through the cervix and into the uterus. The tube is used to gently scrape a small amount of tissue from the endometrium and then remove the tissue samples. A pathologist views the tissue under a microscope to look for cancer cells.
• Dilatation and curettage: Surgery to remove samples of tissue or the inner lining of the uterus. The cervix is dilated and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Tissue samples may be taken and checked under a microscope for signs of disease. This procedure is also called a D&C.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

• The stage of the cancer (whether it is in the endometrium only, involves the whole uterus, or has spread to other places in the body).
• How the cancer cells look under a microscope.
• Whether the cancer cells are affected by progesterone.

Endometrial cancer is highly curable.

Glossary Terms

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

The lower, narrow end of the uterus that forms a canal between the uterus and vagina.

To heal or restore health; a treatment to restore health.

A spoon-shaped instrument with a sharp edge.

A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called D&C and dilatation and curettage.

In medicine, a fluid that comes out of the body. Discharge can be normal or a sign of disease. Discharge also means release of a patient from care.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

A procedure in which a sample of tissue is taken from the endometrium (inner lining of the uterus) for examination under a microscope. A thin tube is inserted through the cervix into the uterus, and gentle scraping and suction are used to remove the sample.

Cancer that forms in the tissue lining the uterus (the small, hollow, pear-shaped organ in a woman's pelvis in which a baby grows). Most endometrial cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids).

The layer of tissue that lines the uterus.

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the laboratory. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.

The developing offspring from 7 to 8 weeks after conception until birth.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

Periodic discharge of blood and tissue from the uterus. From puberty until menopause, menstruation occurs about every 28 days when a woman is not pregnant.

A part of the body that performs a specific function. For example, the heart is an organ.

A procedure in which cells are scraped from the cervix for examination under a microscope. It is used to detect cancer and changes that may lead to cancer. A Pap test can also show noncancerous conditions, such as infection or inflammation. Also called Pap smear and Papanicoloau test.

A doctor who identifies diseases by studying cells and tissues under a microscope.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

Having to do with the pelvis (the lower part of the abdomen located between the hip bones).

A physical examination in which the health care professional will feel for lumps or changes in the shape of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. The health care professional will also use a speculum to open the vagina to look at the cervix and take samples for a Pap test. Also called internal examination.

The lower part of the abdomen, located between the hip bones.

A type of hormone made by the body that plays a role in the menstrual cycle and pregnancy. Progesterone can also be made in the laboratory. It may be used as a type of birth control and to treat menstrual disorders, infertility, symptoms of menopause, and other conditions.

The likely outcome or course of a disease; the chance of recovery or recurrence.

A cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A drug used to treat certain types of breast cancer in women and men. It is also used to prevent breast cancer in women who have had ductal carcinoma in situ (abnormal cells in the ducts of the breast) and in women who are at a high risk of developing breast cancer. Tamoxifen is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in the breast. Tamoxifen is a type of antiestrogen. Also called tamoxifen citrate.

A group or layer of cells that work together to perform a specific function.

Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.

The small, hollow, pear-shaped organ in a woman's pelvis. This is the organ in which a baby grows. Also called womb.

The muscular canal extending from the uterus to the exterior of the body. Also called birth canal.

Having to do with the vagina (the birth canal).