- The Uterus
- Understanding Cancer
- Uterine Cancer: Who's at Risk
- Recognizing Symptoms
- Treatment for Uterine Cancer
- Side Effects of Cancer Treatment
The uterus is part of a woman's reproductive system. It is
the hollow, pear-shaped organ where a baby grows. The uterus
is in the pelvis between the bladder and the rectum.
The narrow, lower portion of the uterus is the cervix. The
broad, middle part of the uterus is the body, or corpus. The
dome-shaped top of the uterus is the fundus. The fallopian
tubes extend from either side of the top of the uterus to
The wall of the uterus has two layers of tissue. The inner
layer, or lining, is the endometrium. The outer layer is muscle
tissue called the myometrium.
In women of childbearing age, the lining of the uterus grows
and thickens each month to prepare for pregnancy. If a woman
does not become pregnant, the thick, bloody lining flows out
of the body through the vagina. This flow is called menstruation.
Cancer is a group of many related diseases. All cancers begin
in cells, the body's basic unit of life. Cells make up tissues,
and tissues make up the organs of the body.
Normally, cells grow and divide to form new cells as the body
needs them. When cells grow old and die, new cells take their
Sometimes this orderly process goes wrong. New cells form
when the body does not need them, and old cells do not die
when they should. These extra cells can form a mass of tissue
called a growth or tumor.
Tumors can be benign or malignant:
Benign tumors are not cancer. Usually,
doctors can remove them. Cells from benign tumors do not spread
to other parts of the body. In most cases, benign tumors do
not come back after they are removed. Most important, benign
tumors are rarely a threat to life.
Benign Conditions of the Uterus
Fibroids are common benign tumors that grow in the muscle
of the uterus. They occur mainly in women in their forties.
Women may have many fibroids at the same time. Fibroids do
not develop into cancer. As a woman reaches menopause, fibroids
are likely to become smaller, and sometimes they disappear.
Usually, fibroids cause no symptoms and need no treatment.
But depending on their size and location, fibroids can cause
bleeding, vaginal discharge, and frequent urination. Women
with these symptoms should see a doctor. If fibroids cause
heavy bleeding, or if they press against nearby organs and
cause pain, the doctor may suggest surgery or other treatment.
Endometriosis is another benign
condition that affects the uterus. It is most common in women
in their thirties and forties, especially in women who have
never been pregnant. It occurs when endometrial tissue begins
to grow on the outside of the uterus and on nearby organs.
This condition may cause painful menstrual periods, abnormal
vaginal bleeding, and sometimes loss of fertility (ability
to get pregnant), but it does not cause cancer. Women with
endometriosis may be treated with hormones or surgery.
Endometrial hyperplasia is an increase
in the number of cells in the lining of the uterus. It is
not cancer. Sometimes it develops into cancer. Heavy menstrual
periods, bleeding between periods, and bleeding after menopause
are common symptoms of hyperplasia. It is most common after
To prevent endometrial hyperplasia from developing into cancer,
the doctor may recommend surgery to remove the uterus (hysterectomy)
or treatment with hormones (progesterone) and regular followup
Malignant tumors are cancer. They
are generally more serious and may be life threatening. Cancer
cells can invade and damage nearby tissues and organs. Also,
cancer cells can break away from a malignant tumor and enter
the bloodstream or lymphatic system. That is how cancer cells
spread from the original (primary) tumor to form new tumors
in other organs. The spread of cancer is called metastasis.
When uterine cancer spreads (metastasizes) outside the uterus,
cancer cells are often found in nearby lymph nodes, nerves,
or blood vessels. If the cancer has reached the lymph nodes,
cancer cells may have spread to other lymph nodes and other
organs, such as the lungs, liver, and bones.
When cancer spreads from its original place to another part
of the body, the new tumor has the same kind of abnormal cells
and the same name as the primary tumor. For example, if cancer
of the uterus spreads to the lungs, the cancer cells in the
lungs are actually uterine cancer cells. The disease is metastatic
uterine cancer, not lung cancer. It is treated as uterine
cancer, not lung cancer. Doctors sometimes call the new tumor
The most common type of cancer of the uterus begins in the
lining (endometrium). It is called endometrial cancer, uterine
cancer, or cancer of the uterus. In this booklet, we will
use the terms uterine cancer or cancer of the uterus to refer
to cancer that begins in the endometrium.
A different type of cancer, uterine sarcoma, develops in the
muscle (myometrium). Cancer that begins in the cervix is also
a different type of cancer.
Uterine Cancer: Who's at Risk
No one knows the exact causes of uterine cancer. However,
it is clear that this disease is not contagious. No one can
"catch" cancer from another person.
Women who get this disease are more likely than other women
to have certain risk factors. They are:
Age. Cancer of the uterus occurs
mostly in women over age 50.
Endometrial hyperplasia. The risk
of uterine cancer is higher if a woman has endometrial hyperplasia.
This condition and its treatment are described above.
Hormone replacement therapy (HRT). HRT is used to control
the symptoms of menopause, to prevent osteoporosis (thinning
of the bones), and to reduce the risk of heart disease or
Obesity and related conditions. The
body makes some of its estrogen in fatty tissue. That's why
obese women are more likely than thin women to have higher
levels of estrogen in their bodies. High levels of estrogen
may be the reason that obese women have an increased risk
of developing uterine cancer. The risk of this disease is
also higher in women with diabetes or high blood pressure
(conditions that occur in many obese women).
Tamoxifen. Women taking the drug
tamoxifen to prevent or treat breast cancer have an increased
risk of uterine cancer. This risk appears to be related to
the estrogen-like effect of this drug on the uterus.
Race. White women are more likely
than African-American women to get uterine cancer.
Colorectal cancer. Women who have
had an inherited form of colorectal cancer have a higher risk
of developing uterine cancer than other women.
Other risk factors are related to how long a woman's body
is exposed to estrogen. Women who have no children, begin
menstruation at a very young age, or enter menopause late
in life are exposed to estrogen longer and have a higher risk.
Women with known risk factors and those who are concerned
about uterine cancer should ask their doctor about the symptoms
to watch for and how often to have checkups. The doctor's
advice will be based on the woman's age, medical history,
and other factors.
Uterine cancer usually occurs after menopause. But it may
also occur around the time that menopause begins. Abnormal
vaginal bleeding is the most common symptom of uterine cancer.
Bleeding may start as a watery, blood-streaked flow that gradually
contains more blood. Women should not assume that abnormal
vaginal bleeding is part of menopause.
A woman should see her doctor if she has any of the following
Unusual vaginal bleeding or discharge
Difficult or painful urination
Pain during intercourse
Pain in the pelvic area
These symptoms can be caused by cancer or other less serious
conditions. Most often they are not cancer, but only a doctor
can tell for sure.
If a woman has symptoms that suggest uterine cancer, her
doctor may check general signs of health and may order blood
and urine tests. The doctor also may perform one or more of
the exams or tests described on the next pages.
Pelvic exam -- A woman has a pelvic
exam to check the vagina, uterus, bladder, and rectum. The
doctor feels these organs for any lumps or changes in their
shape or size. To see the upper part of the vagina and the
cervix, the doctor inserts an instrument called a speculum
into the vagina.
Pap test -- The doctor collects
cells from the cervix and upper vagina. A medical laboratory
checks for abnormal cells. Although the Pap test can detect
cancer of the cervix, cells from inside the uterus usually
do not show up on a Pap test. This is why the doctor collects
samples of cells from inside the uterus in a procedure called
Transvaginal ultrasound -- The
doctor inserts an instrument into the vagina. The instrument
aims high-frequency sound waves at the uterus. The pattern
of the echoes they produce creates a picture. If the endometrium
looks too thick, the doctor can do a biopsy.
Biopsy -- The doctor removes a
sample of tissue from the uterine lining. This usually can
be done in the doctor's office. In some cases, however, a
woman may need to have a dilation and curettage (D&C).
A D&C is usually done as same-day surgery with anesthesia
in a hospital. A pathologist examines the tissue to check
for cancer cells, hyperplasia, and other conditions. For a
short time after the biopsy, some women have cramps and vaginal
If uterine cancer is diagnosed, the doctor needs to know
the stage, or extent, of the disease to plan the best treatment.
Staging is a careful attempt to find out whether the cancer
has spread, and if so, to what parts of the body.
The doctor may order blood and urine tests and chest x-rays.
The woman also may have other x-rays, CT scans, an ultrasound
test, magnetic resonance imaging (MRI), sigmoidoscopy, or
In most cases, the most reliable way to stage this disease
is to remove the uterus (hysterectomy). (The description of
surgery in the "Methods of Treatment" section has
more information.) After the uterus has been removed, the
surgeon can look for obvious signs that the cancer has invaded
the muscle of the uterus. The surgeon also can check the lymph
nodes and other organs in the pelvic area for signs of cancer.
A pathologist uses a microscope to examine the uterus and
other tissues removed by the surgeon.
These are the main features of each stage of the disease:
Stage I -- The cancer is only in the body of the uterus. It
is not in the cervix.
Stage II -- The cancer has spread from the body of the uterus
to the cervix.
Stage III -- The cancer has spread outside the uterus, but
not outside the pelvis (and not to the bladder or rectum).
Lymph nodes in the pelvis may contain cancer cells.
Stage IV -- The cancer has spread into the bladder or rectum.
Or it has spread beyond the pelvis to other body parts.
Treatment for Uterine Cancer
Women with uterine cancer have many treatment options. Most
women with uterine cancer are treated with surgery. Some have
radiation therapy. A smaller number of women may be treated
with hormonal therapy. Some patients receive a combination
Most women with uterine cancer have surgery to remove the
uterus (hysterectomy) through an incision in the abdomen.
The doctor also removes both fallopian tubes and both ovaries.
(This procedure is called a bilateral salpingo-oophorectomy.)
The doctor may also remove the lymph nodes near the tumor
to see if they contain cancer. If cancer cells have reached
the lymph nodes, it may mean that the disease has spread to
other parts of the body. The length of the hospital stay may
vary from several days to a week.
In radiation therapy, high-energy
rays are used to kill cancer cells. Like surgery, radiation
therapy is a local therapy. It affects cancer cells only in
the treated area.
Some women with Stage I, II, or III uterine cancer need both
radiation therapy and surgery. They may have radiation before
surgery to shrink the tumor or after surgery to destroy any
cancer cells that remain in the area. Also, the doctor may
suggest radiation treatments for the small number of women
who cannot have surgery.
Doctors use two types of radiation therapy to treat uterine
External radiation: In external
radiation therapy, a large machine outside the body is used
to aim radiation at the tumor area. The woman is usually an
outpatient in a hospital or clinic and receives external radiation
5 days a week for several weeks. This schedule helps protect
healthy cells and tissue by spreading out the total dose of
radiation. No radioactive materials are put into the body
for external radiation therapy.
Internal radiation: In internal
radiation therapy, tiny tubes containing a radioactive substance
are inserted through the vagina and left in place for a few
days. The woman stays in the hospital during this treatment.
To protect others from radiation exposure, the patient may
not be able to have visitors or may have visitors only for
a short period of time while the implant is in place. Once
the implant is removed, the woman has no radioactivity in
Some patients need both external and internal radiation therapies.
Hormonal therapy involves substances that prevent cancer cells
from getting or using the hormones they may need to grow.
Hormones can attach to hormone receptors, causing changes
in uterine tissue. Before therapy begins, the doctor may request
a hormone receptor test. This special lab test of uterine
tissue helps the doctor learn if estrogen and progesterone
receptors are present. If the tissue has receptors, the woman
is more likely to respond to hormonal therapy.
Hormonal therapy is called a systemic
therapy because it can affect cancer cells throughout the
body. Usually, hormonal therapy is a type of progesterone
taken as a pill.
The doctor may use hormonal therapy for women with uterine
cancer who are unable to have surgery or radiation therapy.
Also, the doctor may give hormonal therapy to women with uterine
cancer that has spread to the lungs or other distant sites.
It is also given to women with uterine cancer that has come
Side Effects of Cancer Treatment
Because cancer treatment may damage healthy cells and tissues,
unwanted side effects sometimes occur. These side effects
depend on many factors, including the type and extent of the
treatment. Side effects may not be the same for each person,
and they may even change from one treatment session to the
next. Before treatment starts, doctors and nurses will explain
the possible side effects and how they will help you manage
After a hysterectomy, women usually have some pain and feel
extremely tired. Most women return to their normal activities
within 4 to 8 weeks after surgery. Some may need more time
Some women may have problems with nausea and vomiting after
surgery, and some may have bladder and bowel problems. The
doctor may restrict the woman's diet to liquids at first,
with a gradual return to solid food.
Women who have had a hysterectomy no longer have menstrual
periods and can no longer get pregnant. When the ovaries are
removed, menopause occurs at once. Hot flashes and other symptoms
of menopause caused by surgery may be more severe than those
caused by natural menopause. Hormone replacement therapy (HRT)
is often given to women who have not had uterine cancer to
relieve these problems. However, doctors usually do not give
the hormone estrogen to women who have had uterine cancer.
Because estrogen is a risk factor for this disease (see "Uterine
Cancer: Who's at Risk?"), many doctors are concerned
that estrogen may cause uterine cancer to return. Other doctors
point out that there is no scientific evidence that estrogen
increases the risk that cancer will come back. NCI is sponsoring
a large research study to learn whether women who have had
early stage uterine cancer can take estrogen safely.
For some women, a hysterectomy can affect sexual intimacy.
A woman may have feelings of loss that may make intimacy difficult.
Sharing these feelings with her partner may be helpful.
The side effects of radiation therapy depend mainly on the
treatment dose and the part of the body that is treated. Common
side effects of radiation include dry, reddened skin and hair
loss in the treated area, loss of appetite, and extreme tiredness.
Some women may have dryness, itching, tightening, and burning
in the vagina. Radiation also may cause diarrhea or frequent
and uncomfortable urination. It may reduce the number of white
blood cells, which help protect the body against infection.
Doctors may advise their patients not to have intercourse
during radiation therapy. However, most can resume sexual
activity within a few weeks after treatment ends. The doctor
or nurse may suggest ways to relieve any vaginal discomfort
related to treatment.
Hormonal therapy can cause a number of side effects. Women
taking progesterone may retain fluid, have an increased appetite,
and gain weight. Women who are still menstruating may have
changes in their periods.