Cancer of the uterus develops in the lining of the uterus (endometrium) and is thus also called endometrial cancer.
- Endometrial cancer usually affects women after menopause.
- It sometimes causes abnormal vaginal bleeding.
- To diagnose this cancer, doctors remove a sample of tissue from the endometrium to be analyzed (biopsy).
- Usually, the uterus, ovaries, and fallopian tubes and sometimes the nearby lymph nodes are removed, often followed by radiation therapy and sometimes by chemotherapy or hormone therapy.
(See also Overview of Female Reproductive System Cancers.)
Most cancers of the uterus begin in the lining of the uterus (endometrium) and are more precisely termed endometrial cancer (carcinoma). In the United States, it is the most common gynecologic cancer and the fourth most common cancer among women. This cancer usually develops after menopause, most often in women aged 50 to 60. Over 90% of cases occur in women over 50.
About 75 to 80% of endometrial cancers are adenocarcinomas, which develop from gland cells. Fewer than 5% of cancers in the uterus are sarcomas. Sarcomas develop from connective tissue and tend to be more aggressive.
Endometrial cancer is often classified as follows:
- Type I cancers are more common, respond to estrogen, and are not very aggressive. They tend to occur in younger or obese women or in women going through perimenopause (the years just before and the year after the last menstrual period). The prognosis for women with type I cancers is good.
- Type II cancers are more aggressive and tend to occur in older women. About 10% of endometrial cancers are type II. The prognosis for women with type II cancers is poor.
Causes of Uterine Cancer
Endometrial cancer is more common in developed countries where the diet is high in fat.
The most important risk factors for endometrial cancer are
- Age over 50
- Conditions that result in a high level of estrogen but not progesterone
Other risk factors for endometrial cancer include the following:
- Having had cancer of the breast or ovaries
- Having had or having a family member who has had cancer of the breast or ovaries, a certain hereditary form of cancer of the large intestine (colon), or possibly, endometrial cancer in a first-degree family member (mother, sister, or daughter)
- Having had radiation therapy directed at the pelvis
- Using tamoxifen for 5 years or longer
- Having high blood pressure
Conditions that result in a high level of estrogen but not progesterone include the following:
- Starting menstrual periods (menarche) early, reaching menopause after age 52, or both
- Having menstrual problems related to release of the egg (ovulation), usually with symptoms such as excessive bleeding during periods, spotting between periods, or long intervals without periods
- Not having any children
- Having polycystic ovary syndrome
- Being obese
- Having tumors that produce estrogen
- Taking drugs that contain estrogen, such as estrogen therapy without a progestin (a synthetic drug similar to the hormone progesterone), after menopause
Estrogen promotes the growth of tissue and rapid cell division in the lining of the uterus (endometrium). Progesterone helps balance the effects of estrogen. Levels of estrogen are high during part of the menstrual cycle. Thus, having more menstrual periods during a lifetime may increase the risk of endometrial cancer. Tamoxifen, a drug used to treat breast cancer, blocks the effects of estrogen in the breast, but it has the same effects as estrogen in the uterus. Thus, this drug may increase the risk of endometrial cancer. Taking oral contraceptives that contain estrogen and a progestin appears to reduce the risk of endometrial cancer.
In about 5% of women with endometrial cancer, heredity plays a role. About half of endometrial cancers that involve heredity occur in women who have or who have relatives who have a hereditary form of colon cancer called Lynch syndrome (hereditary nonpolyposis colorectal cancer).
Symptoms of Uterine Cancer
Abnormal bleeding from the vagina is the most common early symptom of endometrial cancer. Abnormal bleeding includes
- Bleeding after menopause
- Bleeding between menstrual periods
- Periods that are irregular, heavy, or longer than normal
About one of three women with vaginal bleeding after menopause has endometrial cancer. Women who have vaginal bleeding after menopause should see a doctor promptly. A watery, blood-tinged discharge may also occur. Postmenopausal women may have a vaginal discharge for several weeks or months, followed by vaginal bleeding.
Diagnosis of Uterine Cancer
- Sometimes dilation and curettage with hysteroscopy
Doctors may suspect endometrial cancer if one of the following is present:
- Women have typical symptoms, such as vaginal bleeding after menopause or between periods or irregular, heavy, or unusually long periods
- Results of a Papanicolaou (Pap) test, usually done as part of a routine examination, are abnormal.
If cancer is suspected, doctors take a sample of tissue from the endometrium (endometrial biopsy) in their office and send it to a laboratory for analysis. An endometrial biopsy accurately detects endometrial cancer more than 90% of the time.
If the diagnosis is still uncertain or suggests cancer, doctors scrape tissue from the uterine lining for analysis—a procedure called dilation and curettage (D and C). At the same time, doctors usually view the interior of the uterus using a thin, flexible viewing tube inserted through the vagina and cervix into the uterus in a procedure called hysteroscopy. Alternatively, an ultrasound device may be inserted through the vagina into the uterus (called transvaginal ultrasonography) to evaluate abnormalities. However, a biopsy is still necessary to make the diagnosis.
If endometrial cancer is diagnosed, some or all of the following procedures may be done:
- Blood tests
- Kidney and liver function tests (using samples of blood or urine)
- A chest x-ray
If results of the physical examination or other tests suggest that the cancer has spread beyond the uterus, computed tomography (CT) is done. Other procedures are sometimes required.
Staging of endometrial cancer
Staging is based on information obtained from these procedures and during surgery to remove the cancer.
Stages are based on how far the cancer has spread. Stages range from I (the earliest) to IV (advanced):
- Stage I: The cancer occurs only in the upper part of the uterus, not in the lower part (cervix).
- Stage II: The cancer has spread to the cervix.
- Stage III: The cancer has spread to nearby tissues, the vagina, or lymph nodes.
- Stage IV: The cancer has spread to the bladder and/or intestine or to distant organs.
Prognosis of Uterine Cancer
Prognosis depends on the stage of the endometrial cancer.
The percentages of women who are alive 5 years after diagnosis and treatment (5-year survival rate) are
- Stage I or II: 70 to 95% (most are cured)
- Stage III or IV: 10 to 60%
Overall, 63% of women are cancer-free 5 years after treatment.
Generally, the prognosis is better if
- Endometrial cancer has not spread beyond the uterus.
- The cancer grows relatively slowly.
- Women are younger when the cancer is detected.
Prognosis is generally worse with sarcomas than with adenocarcinomas in women with endometrial cancer.
Prevention of Uterine Cancer
No measure can prevent endometrial cancer from developing. However, the risk of getting endometrial cancer can be decreased by minimizing or avoiding conditions and activities thought to increase the risk. For example, obesity and high blood pressure increase the risk of endometrial cancer. Thus, losing weight, exercising regularly, and eating a healthful diet may be helpful.
Treatment of Uterine Cancer
- Removal of the uterus, fallopian tubes, and ovaries
- Removal of nearby lymph nodes
- For more advanced cancer, radiation therapy with or without chemotherapy
Hysterectomy (surgical removal of the uterus) is the mainstay of treatment for women who have endometrial cancer. Unless the cancer is very advanced, hysterectomy improves the prognosis.
Nearby lymph nodes are usually removed at the same time. These tissues are examined by a pathologist to determine whether the cancer has spread and, if so, how far it has spread. With this information, doctors can determine whether additional treatment (chemotherapy, radiation therapy, or a progestin) is needed after surgery. When the cancer appears confined to the uterus, doctors may do sentinel lymph node dissection instead of removing all the lymph nodes.
Doctors can remove the uterus, fallopian tubes, and ovaries using one of the following methods:
- Making an incision in the abdomen (open surgery)
- Using a thin viewing tube (laparoscope) inserted through a small incision just below the navel, then threading instruments through the laparoscope, sometimes with robotic assistance (laparoscopic surgery)
- Removing the tissues through the vagina (vaginal surgery)
Treatment of endometrial cancer that has not spread outside the uterus
If the cancer has not spread beyond the uterus, removal of the uterus plus removal of the fallopian tubes and ovaries (salpingo-oophorectomy) almost always cures the cancer.
Treatment of endometrial cancer that has spread to the cervix or to nearby tissues, the vagina, or lymph nodes
If cancer has spread to the cervix (stage II) or to nearby tissues, the vagina, or lymph nodes (stage III), radiation therapy, with or without chemotherapy, is required. Surgery to remove the uterus, fallopian tubes, and ovaries is usually also done.
Treatment of very advanced endometrial cancer
For very advanced cancer (stage IV), treatment varies but usually involves a combination of surgery, radiation therapy, chemotherapy, and occasionally hormone therapy with a progestin (a synthetic drug similar to the hormone progesterone).
Radiation therapy may be given after surgery in case some undetected cancer cells remain. If the cancer has spread to the cervix or beyond the uterus, radiation therapy is usually recommended after surgery. In some cases (as when cancer has spread to the cervix, an ovary, or lymph nodes), surgery plus radiation therapy results in a better prognosis.
If the cancer has spread to distant organs or recurs, chemotherapy drugs (such as carboplatin, cisplatin, doxorubicin, and paclitaxel) may be used instead of or sometimes with radiation therapy. These drugs reduce the cancer’s size and control its spread in more than half of women treated. However, these drugs are toxic and have many side effects.
Sometimes progestins are used. These drugs are much less toxic than chemotherapy drugs.
Treatment of sarcoma of the uterus
For sarcoma of the uterus (a more aggressive form of endometrial cancer), treatment is hysterectomy plus removal of the fallopian tubes and ovaries (salpingo-oophorectomy) and usually chemotherapy.
If surgery is not possible, radiation and/or chemotherapy is used.
A hysterectomy is the removal of the uterus.
The uterus may be removed through an incision in the lower abdomen (open surgery). Sometimes the uterus can be removed through the vagina (vaginal surgery). Either method usually takes about 1 to 2 hours and requires a general anesthetic. Afterward, vaginal bleeding and pain may occur. The hospital stay is usually 2 to 3 days, and recovery may take up to 6 weeks. When the uterus is removed through the vagina, less bleeding occurs, recovery is faster, and there is no visible scar.
Because of advances in technology, hysterectomy may also be done using laparoscopic or robotic-assisted laparoscopic surgery.
- Laparoscopic surgery: Thin instruments and a small video camera are inserted through tiny incisions near the navel. The camera sends an image of the abdomen's interior to a monitor. While looking at the monitor, surgeons hold the instruments in their hands and use them to cut and sew tissue.
- Robotic-assisted laparoscopic surgery: Laparoscopy is done in the usual way. But robotic arms, rather than surgeons, hold the instruments. Surgeons use hand controls to manipulate the arms of the robot. The camera used provides a 3-dimensional, highly detailed (high-definition) image of the interior that is displayed on a console. Surgeons sit at the console to view this image and use a computer that translates their hand movements into precise movements of the instruments.
After either laparoscopic procedure, the hospital stay is only 1 day. Women usually have less pain and fewer complications and can return more quickly to normal activities after laparoscopic surgery than after open surgery (which involves a larger incision).
In addition to treating certain gynecologic cancers, a hysterectomy may be used to treat prolapse of the uterus, endometriosis, or fibroids (if causing severe symptoms). Sometimes it is done as part of the treatment for cancer of the colon, rectum, or bladder.
There are several types of hysterectomy. The type used depends on the disorder being treated.
- Subtotal (supracervical) hysterectomy: Only the upper part of the uterus is removed, but the cervix is not. The fallopian tubes and ovaries may or may not be removed.
- Total hysterectomy: The entire uterus including the cervix is removed.
- Radical hysterectomy: The entire uterus plus the surrounding tissues (including the upper part of the vagina, ligaments, and usually lymph nodes) are removed. Both fallopian tubes and ovaries are usually also removed in women older than 45.
For endometrial cancer or fallopian tube cancer, total hysterectomy is usually done. For cervical cancer or vaginal cancer, treatment may include radical hysterectomy.
After a hysterectomy, menstruation stops. However, a hysterectomy does not cause menopause unless the ovaries are removed also. Removal of the ovaries has the same effects as menopause, so hormone therapy may be recommended.
Many women anticipate feeling depressed or losing interest in sex after a hysterectomy. However, hysterectomy rarely has these effects unless the ovaries are also removed.
If menopausal symptoms such as hot flashes and vaginal dryness become bothersome after the uterus is removed, hormones such as estrogen, a progestin, or both can taken to relieve them. This treatment is safe and does not increase the risk of developing cancer again.
Sentinel lymph node dissection
A sentinel lymph node is the first lymph node that cancer cells are likely to spread to. There may be more than one sentinel lymph node. These nodes are called sentinel lymph nodes because they are the first to warn that cancer has spread.
A sentinel lymph node dissection involves
- Identifying the sentinel lymph node (called mapping)
- Removing it
- Examining it to determine whether cancer cells are present
To identify sentinel lymph nodes, doctors inject a blue or green dye and/or a radioactive substance, usually into the cervix. These substances travel to the lymph nodes near the uterus and map the pathway from the uterus to the lymph node (or nodes) nearest the uterus. During surgery, doctors check for lymph nodes that look blue or green or that give off a radioactive signal (detected by a handheld device). Doctors remove this node (or nodes) and send it to a laboratory to be checked for cancer. If the sentinel lymph node or nodes do not contain cancer cells, no other lymph nodes are removed (unless they look abnormal).
When the cancer appears confined to the uterus, doctors may do sentinel lymph node mapping and dissection instead of removing all the lymph nodes.
Pregnancy and endometrial cancer
Treatment with radical hysterectomy, chemotherapy, and/or radiation therapy usually makes it impossible for women to become pregnant or to carry a pregnancy to term. However, advances in assisted reproductive techniques may enable women to have a child after these procedures. If being able to have children is important to them, women should talk to their doctor and get as much information as possible about risks of and requirements for these procedures, as well as the likelihood of becoming pregnant and having a child after such a procedure.
If endometrial cancer is in a very early stage, fertility preservation treatment can sometimes be used. Magnetic resonance imaging (MRI) is done to determine whether the tumor has spread, and a fertility specialist is consulted.
Fertility preservation treatments include
- Use of a progestin (a synthetic drug similar to the hormone progesterone), which can shrink the tumor
- Use of an intrauterine device (IUD) that releases levonorgestrel (a progestin)
- Rarely, fertility-preserving (conservative) surgery
In fertility-preserving surgery, doctors remove only the tumor and the tissue around and under the tumor.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
- National Cancer Institute: Uterine Cancer: This web site provides links to general information about uterine cancer, as well as links to information about causes, prevention, screening, treatment, and research and about coping with cancer.
Drugs Mentioned In This Article
|Generic Name||Select Brand Names|
|levonorgestrel||MIRENA, PLAN B|
|carboplatin||No US brand name|