What
Is Ovarian Cancer?
Ovarian cancer begins in the ovaries. Women have two
ovaries, one on each side of the uterus in the pelvis.
The ovaries produce eggs (called ova). They are also
the main source of a woman’s female hormones,
estrogen and progesterone. The eggs travel through
the fallopian tubes to the uterus. Here they may be
fertilized and develop into a fetus. Cancer can also
begin in the fallopian tubes.

The ovaries contain 3 kinds of tissue:
Germ cells: These cells
make eggs (ova) inside of the ovary.
Stromal cells: These
cells are inside the ovary, between germ cells. They
make most of the female hormones (estrogen and progesterone).
Epithelial cells: These
cells cover the ovary. Most ovarian cancers start
in this covering.
Epithelial cells: These
cells cover the ovary. Most ovarian cancers start
in this covering.
Many types of tumors can start in the ovaries. Some
are benign (non-cancerous) and never spread beyond
the ovary. Women with these types of tumors can be
successfully treated by removing one ovary or the
part of the ovary that has the tumor. Other types
of tumors are cancerous (malignant) and can spread
to other parts of the body. Their treatment is complicated.
It is explained later in this article.
As a rule, tumors in the ovary are named for the kinds
of cells the tumor started from and whether the tumor
is benign or cancerous. There are three main types
of tumors:
Germ cell tumors start from the cells that produce
the eggs.
Stromal tumors start
from connective tissue cells that hold the ovary together
and make the female hormones.
Epithelial tumors start from the cells that cover
the outer surface of the ovary
Types of Ovarian Cancer
Epithelial Ovarian Tumors
Epithelial ovarian tumors are further divided into
3 sub-groups:
Benign epithelial tumors: these tumors do not spread
and usually do not lead to serious illness.
Tumors of low malignant potential
(LMP tumors): These do not clearly appear
to be cancerous when looked at under the microscope.
They are also known as borderline tumors. These tumors
affect women at a younger age than other ovarian cancers.
They grow and spread slowly and are much less serious
than most ovarian cancers.
Epithelial ovarian cancers:
Nearly 9 out of 10 ovarian cancers are this type.
Cancer cells of this type have certain features that
can be seen under a microscope which allow doctors
to further classify them. These tumors are also given
a grade depending on how much the cells look like
normal cells. Grade 1 means the cells look more normal;
grade 3 look less normal, and grade 2 is in between.
Usually the higher the grade the worse the outlook.
Primary Peritoneal Carcinoma
This condition is a cancer much like epithelial ovarian
cancer but it starts outside of the ovaries. It grows
from the cells that line the pelvis and abdomen. These
cells look just like the cells along the surface of
the ovaries. Women who have had their ovaries removed
can still get this type of cancer. Symptoms of this
cancer are much like those of ovarian cancer. Treatment
is also similar.
Germ Cell Tumors
About 1 in 20 ovarian cancers are germ cell tumors.
Germ cells make the eggs. Most germ cell tumors are
not cancer, although some can be. There are several
sub-types of germ cell tumors.
Stromal Tumors
Stromal tumors can be either benign (non-cancerous)
or cancerous. More than half are found in women over
age 50. Some of these tumors make hormones. There
are many different types of stromal tumors. Treatment
depends on the type.
Ovarian Cysts
An ovarian cyst is fluid that collects inside an ovary.
Many of these cysts are harmless. The fluid will most
often be absorbed and the cyst will go away in time
without any treatment. But if the cyst is large or
happens in childhood or after menopause, the doctor
may suggest further tests or treatment. This is because
a very small number of these cysts can be cancerous.
Fallopian Tube Cancer
This is an extremely rare cancer. The cancer begins
in the fallopian tube. The symptoms are similar to
those in women with ovarian cancer, except that there
may be more pelvic pain. Treatment and outlook is
similar to that for ovarian cancer.
How Many Women Get Ovarian Cancer?
Ovarian cancer is the eighth most common cancer in
women (not counting skin cancer). It ranks fifth as
the cause of cancer death in women. The American Cancer
Society estimates that there will be about 20,180
new cases of ovarian cancer in this country in 2006.
About 15,310 women will die this year because of the
disease. Around two-thirds of women with ovarian cancer
are 55 or older. It is slightly more common in white
women that African-American women.
The rate of ovarian cancer has gone down about 0.7%
per year since 1985. A woman's risk of getting ovarian
cancer during her lifetime is about 1 in 67. The risk
of getting this cancer and dying from it is 1 in 95.
What Causes Ovarian Cancer?
We do not yet know what causes ovarian cancer. But
we do know some of the risk factors involved. A risk
factor is something that increases a person's chance
of getting a disease. Different cancers have different
risk factors. Some risk factors, such as smoking,
can be controlled. Others, like a person's age or
race, can't be changed.
Most cases of ovarian cancer are not explained by
any known risk factors. It is important to remember
that while risk factors increase the odds of getting
a disease, they do not guarantee it will occur.
Here are some of the risk factors for the most common
type, epithelial ovarian cancer:
Age: Most ovarian cancers happen after change of life
(menopause). Half of all these cancers are found in
women over the age of 63.
Obesity: A study from
the ACS found a higher rate of death from ovarian
cancer in women who were overweight. The risk went
up by 50% in the heaviest women.
Menstrual periods: There
seems to be a link between the number of periods (menstrual
cycles) in a woman's lifetime and her risk of getting
ovarian cancer. Women who started having periods early
(before 12 years of age) or who went through the change
of life (menopause) after the age of 50 have a small
increased risk of ovarian cancer. The same is true
for women who have not had children, or had their
first child after they were 30 years old.
Fertility drugs: Some
studies have found that long-time use of one fertility
drug (clomiphene citrate), especially if no pregnancy
took place, may increase the risk of LMP tumors. But
infertility also increases the risk, even without
the use of fertility drugs. Research in this area
is now going on. If you are taking this drug, you
should talk to your doctor about the possible risks.
Family history: Ovarian
cancer risk is higher among women whose close blood
relatives (mother, sister, daughter) have (or had)
this disease. The relatives can be from either the
mother's or father's side of the family. There is
a higher risk if ovarian cancer happened at an early
age. About 1 in 10 cases of ovarian cancers are linked
to gene changes that can be found with certain tests.
These changes are also linked to an increased risk
of breast and colorectal cancer. Please see the section
on prevention to learn about genetic counseling and
testing.
Breast cancer: Women
who have had breast cancer also have a higher risk
of ovarian cancer.
Talcum powder: Some
studies have shown a slight increase in risk of ovarian
cancer among women who used talcum powder on the genital
area. Asbestos in the powder may explain the link.
But these products have been free of asbestos for
more than 20 years. Proving the safety of newer products
will require further follow-up studies.
Estrogen replacement therapy
(ERT): Some studies suggest that women using
estrogens after menopause may have an increased risk
of ovarian cancer, but other studies have not found
any effect. Most of these findings have been for women
who used estrogen alone, not those taking combined
estrogen and progesterone. The increased risk is less
certain for women taking both drugs. Because of the
small number of studies, doctors are not sure whether
estrogens increase the risk of ovarian cancer.
Smoking and alcohol use:
Some studies have found an increased risk for one
type of ovarian cancer (mucinous).
Can Ovarian Cancer Be Prevented?
Most women have one or more risk factors for ovarian
cancer. But risk factors only partly explain the disease,
since most of them increase risk only slightly. So
far, knowledge about risk factors has not led to ways
to prevent the disease.
Some of the actions listed below may reduce the risk
of the most common type of ovarian cancer (epithelial)
only slightly, while others may decrease it much more.
If you are concerned about your risk, especially if
you have a family history of cancer, you should discuss
this information with your doctor.
Birth control pills:
Birth control pills reduce the risk of ovarian cancer,
especially among women who use them for several years.
Tubal ligation or hysterectomy:
"Tying" the tubes as a method of birth control, when
done after childbearing, may reduce the chance of
ovarian cancer. Removing the uterus may also reduce
the risk. But these surgeries should only be done
for a valid medical reason and not just for their
effect on ovarian cancer risk.
Pregnancy and breast-feeding:
Having one or more children plus breast-feeding for
a year or longer may decrease the risk of ovarian
cancer. Although these measures slightly reduce the
risk, they don't offer complete protection. Doctors
do not suggest making these choices about when to
have a child simply for the purpose of reducing ovarian
cancer risk. Keep in mind that using the birth control
pill has a greater impact on this risk.
Diet: A number of studies
have shown a lower rate of this cancer in women who
ate a diet high in vegetables. The American Cancer
Society recommends eating a wide variety of healthful
foods, with many from plant sources. Eat at least
5 servings of fruits and vegetables every day. Limit
the amount of red meats, especially those that are
high in fat.
Aspirin and acetaminophen:
Some studies have shown that both aspirin and acetaminophen
(Tylenol) reduce the risk of ovarian cancer. But there
is some doubt about this. Women should not take these
drugs simply to prevent this cancer. More research
is needed.
Women with a family history of ovarian cancer might
want to think about genetic counseling and perhaps
genetic testing. Before asking for the test, a woman
should discuss the benefits and possible drawbacks
with her doctor. Genetic testing can tell if a woman
carries certain gene changes that cause a higher risk
of ovarian cancer. Learning that she does not have
the gene change can be a great relief, while finding
out that she does can be quite stressful. Still, the
information can be helpful in looking at methods to
prevent cancer.
Studies looking at whether the birth control pill
could lower the risk of ovarian cancer have shown
mixed results. For women at average risk, the pill
does lower the risk. But for women at high risk because
of gene changes, the results are mixed. More research
is needed to make clear the pros and cons of the pill
for women at high risk of ovarian or breast cancer.
Surgery to remove one or both ovaries is called oophorectomy.
It can be done before a cancer develops in order to
lower the risk. But whether or not a woman should
have this surgery is open to question because it causes
change of life (menopause) to take place early. Often,
doctors suggest it only for certain women over the
age of 40 who are at very high risk. While this operation
lowers ovarian cancer risk a great deal, cancer can
still form in the cells lining the pelvis where the
ovaries were located.
How Is Ovarian Cancer Found?
About one fifth of ovarian cancers are found at an
early stage. Finding the cancer early improves the
chances that it can be treated successfully. Nine
out of 10 women treated for early ovarian cancer will
live longer than 5 years after the cancer is found.
Unfortunately, there is no reliable test for finding
this cancer early, but several large studies are in
progress to learn how best to find ovarian cancer
in its earliest stage.
Ways to Find Ovarian Cancer Early
Regular women's health exams: During a pelvic exam
the doctor will feel the female organs to check their
size and shape. But most ovarian tumors are hard to
find early because the ovaries are deep within the
body and the doctor cannot feel them easily. While
the Pap test helps to find cervical cancer early,
it is not really useful for finding ovarian cancer
at an early stage.
See a doctor if you have symptoms: Early cancers of
the ovaries tend to cause somewhat vague symptoms.
Keep in mind that these problems are often caused
by something other than cancer. Symptoms might include:
" swelling of the stomach (abdomen) from a buildup
of fluid
" unusual vaginal bleeding
" pelvic pressure
" back or leg pain
" problems such as gas, bloating, long-term stomach
pain, constipation, or indigestion
By the time ovarian cancer is thought of as a possible
cause of these symptoms, it may already have spread
beyond the ovaries. Also, some types of ovarian cancer
can quickly spread to the surface of nearby organs.
Still, prompt attention to symptoms can improve the
odds of finding the cancer early and treating it successfully.
If you have any of the symptoms above, report them
to your doctor right away.
Screening tests: These
tests and exams are used to find a disease such as
cancer in people who don't have any symptoms. Women
with a high risk of ovarian cancer (such as those
with a strong family history of the disease) may be
screened with ultrasound and with blood tests. But
early studies of women at average risk of ovarian
cancer show that these tests did not lower the number
of deaths caused by ovarian cancer. For this reason,
these tests are not used for routine screening of
women who don't have strong risk factors.
If there is any reason to suspect ovarian cancer,
the doctor will use one or more methods to find out
if the disease is really present. One of the first
steps will be a meeting with a doctor who has special
training in treating women with this type of cancer
(a gynecologic oncologist). Following are some of
the tests that could be done:
Imaging Studies
These tests can show whether there is a mass in the
pelvis, but they cannot tell whether it is cancer.
Ultrasound: This test
uses sound waves to create an image on a video screen.
Because tumors and normal tissue reflect sound waves
differently, this test may be useful in finding tumors
and in telling whether a mass is solid or a fluid-filled
cyst.
CT scans (computed tomography):
These scans use an x-ray beam to take a series of
pictures of the body from many angles. A computer
combines the pictures to form a detailed image. CT
scans are useful in showing how large the tumor is,
whether lymph nodes are enlarged, and whether the
tumor has spread to other organs. CT scans can also
be used to guide a biopsy needle into a tumor in order
to remove a sample of tissue.
CT scans take longer than regular x-rays. You will
need to lie still on a table while they are being
done. Also, some contrast dye will be injected or
you may be asked to drink a contrast fluid.
Barium enema x-rays:
These can be done to see whether the cancer has spread
to the large intestine or rectum. A chalky substance
(barium sulfate) will be placed into the rectum and
colon. The barium outlines the colon and rectum on
x-rays.
Colonoscopy: After you
have taken a laxative, the doctor inserts a tube into
the rectum and into the colon. Through this, the doctor
can see inside and spot any cancer. Because it is
uncomfortable, you will be sedated. This test is also
used to look for colorectal cancer.
MRI (magnetic resonance imaging):
Like a CT scan, MRIs display a cross-sectional picture
of the body. But an MRI uses radio waves and strong
magnets instead of x-rays. MRI scans are helpful in
looking at the brain and spinal cord. These scans
take longer than CT scans, often up to 30 minutes
or more.
Chest x-rays: These
may be taken to see if the cancer has spread to the
lungs.
PET (Positron emission tomography): PET scans use
a form of radioactive sugar (glucose) to look for
the cancer. Cancers use sugar at a higher rate than
normal tissues. This means that the radioactivity
will tend to collect in the cancer which will make
it visible on the scan. This test is sometimes useful
to find ovarian cancer that has spread.
Other Tests
Laparoscopy (lap-uh-ros-ku-pe):
This is another method that lets the doctor take pictures
of the ovaries and other pelvic organs. A thin, lighted
tube is placed through a small cut (incision) into
the lower abdomen.
Tissue sampling: The
only way to tell for certain if a growth in the pelvis
is cancer involves removing a sample of tissue or
fluid to see if cancer cells are present. This is
called a biopsy and is often done at the time of surgery.
It can also be done as a test separate from the surgery,
such as during a laparoscopy.
Blood tests: These tests
are done to make sure you have the right number of
the different kinds of blood cells. The tests also
measure kidney and liver function, and look for a
substance called CA-125. CA-125 is a protein in the
blood that may be higher than normal in some women
with ovarian cancer. It is sometimes called a tumor
marker for ovarian cancer.
How Is Ovarian Cancer Treated?
After the tests are done, your doctor will suggest
one or more options for treatment. Think about these
options without feeling rushed. If there is anything
you don't understand, ask to have it explained. The
choice of treatment depends largely on the type of
cancer and the stage of the disease. If you have not
had surgery yet, the exact stage may not be known.
In that case, treatment is based on what is known.
Other factors that could play a part in choosing the
best treatment plan might include your general state
of health, whether you plan to have children, and
other personal considerations. Age alone is not a
limiting factor. Studies have shown that older women
can take ovarian cancer treatments well. Be sure you
understand all the risks and side effects of different
treatments before you make a decision.
The main treatments for ovarian cancer are surgery,
chemotherapy, and radiation therapy. In some cases
2 or even all 3 of these treatments will be used.
Surgery
How much and what type of surgery a woman has depends
on how far the cancer has spread, her general health,
and whether or not she still hopes to have children.
Don't be afraid to ask your doctor to explain your
condition and your surgery choices in simple, non-medical
terms.
There are several different types of surgery for ovarian
cancer. The names of these operations are based on
the Greek or Latin names of the organs that are removed.
When something is removed, the name of the operation
often ends in "---ectomy." So, removing the uterus
is a hysterectomy. Because there are two ovaries,
we need to show whether one or both have been removed.
Removing one ovary is a unilateral (one side) oophorectomy,
and removing both is a bilateral (two sides) oophorectomy.
Likewise, removing one or both fallopian tubes is
a unilateral salpingectomy or a bilateral salpingectomy.
If both ovaries or the uterus are removed, you will
not be able to get pregnant. It also means that you
will go through change of life if you haven't already.
Most women will be in the hospital for 3 to 7 days
after surgery. Recovery usually takes about 4 to 6
weeks.
If all of the tumor can't be removed, the surgeon
might remove as much as possible in a procedure called
debulking (or cytoreduction). Most doctors believe
this greatly improves a woman's chance for survival.
Your surgeon should be experienced in ovarian cancer
surgery. Many gynecologists are not prepared to do
this kind of cancer operation, which calls for careful
staging and, perhaps, debulking. For this reason,
many doctors refer their patients to doctors with
special training called gynecologic oncologists. A
gynecologic oncologist is a doctor who works with
women who have cancer of the uterus, ovary, breast,
or other part of the female system.
Chemotherapy
Chemotherapy refers to the use of drugs to kill cancer
cells. Usually the drugs are given into a vein or
by mouth. Once the drugs enter the bloodstream, they
spread throughout the body. This treatment is especially
useful when cancer has spread beyond the ovaries.
The drugs can also be given directly into the abdomen.
This approach aims the drugs right at the cancer cells
and limits the amount reaching the rest of the body.
This helps reduce side effects.
Chemotherapy is usually given in cycles of treatment
followed by a rest period. Chemotherapy is prescribed
by an oncologist (cancer doctor).
While chemotherapy drugs kill cancer cells, they also
damage some normal cells, causing side effects. These
side effects will depend on the type of drugs given,
the amount taken, and how long treatment lasts. Temporary
side effects might include the following:
" nausea and vomiting
" loss of appetite
" hair loss
" hand and foot rashes
" kidney or nerve damage
" mouth sores
" an increased chance of infection (from a shortage
of white blood cells)
" bleeding or bruising after minor cuts (from a shortage
of platelets)
" tiredness (from low red blood cell counts)
Most side effects go away when treatment ends. Hair
will grow back, although it may look different. Some
side effects, such as menopause and infertility, can
be permanent. Rarely, some cancer drugs may cause
another cancer to develop. The small chance that this
might happen should be weighed against the positive
effects of treating the ovarian cancer. Anyone who
has problems with side effects should talk with their
doctor or nurse as there are often ways to help.
Radiation Therapy
Radiation therapy uses high energy x-rays to kill
or shrink cancer cells. The radiation may come from
outside the body or from radioactive materials placed
directly into or near the tumor. However, radiation
therapy is rarely used in this country as the main
treatment for ovarian cancer.
Radiation therapy may cause side effects. The skin
in the area treated may look and feel sunburned. The
skin returns to normal within 6 to 12 months. Many
women also feel tiredness, nausea or diarrhea. Be
sure to talk with the doctor about any side effects.
Often there are ways to help.
Treatment for Epithelial Ovarian
Cancer
The treatment for epithelial ovarian cancer depends
on how far the cancer has grown. Usually the first
option is surgery to remove one or both ovaries. The
doctor may also advise surgery to remove other female
organs. Treatment may include chemotherapy or radiation
therapy for early stage cancers. For stage III and
IV cancers, the tumor will also be debulked.
Chemotherapy is often given after surgery. If cancer
returns after treatment, more surgery and chemotherapy
may be given.
After treatment, blood tests will be done to see if
your CA-125 tumor marker levels are normal.
The most common problems that can occur in women whose
cancer has come back are fluid build-up and blockage
of the intestinal tract. Numbing the skin and inserting
a needle to draw off the fluid can relieve fluid build-up.
This will often need to be done again from time to
time. This can extend life and relieve symptoms for
some women.
Dealing with the intestinal blockage can be harder.
Often the cancer has grown so much that surgery doesn't
fix the problem. Doctors can place a tube through
the skin and into the stomach to relieve fluid build-up
in the digestive tract. The goal is to relieve pain
and keep the woman comfortable.
High dose chemotherapy with stem cell rescue (bone
marrow transplant) has been used for women with cancer
that has come back or not gone away at all. This approach
has serious side effects. And it has not helped patients
to live longer. It should only be done as part of
a clinical trial.
Treatment for Low Malignant Potential
(LMP) Tumors
For LMP (borderline) tumors, the ovary with the tumor
and the fallopian tube on the affected side are usually
removed. In certain cases, just the ovarian cyst with
the tumor is removed. If the woman might want to become
pregnant in the future, and if there appears to be
no cancer beyond the one ovary, no further surgery
is done at that time.
If the woman is not concerned about being able to
have children, the ovaries, fallopian tubes, and the
uterus are removed. Chemotherapy and radiation are
not generally used at first for treatment of these
tumors, although they may be used if the tumor comes
back after surgery.
Treatment for Germ Cell Tumors
of the Ovary
Women with benign germ cell tumors are cured by removing
part or all of the ovary and the fallopian tube on
the affected side. It's a good idea to consult with
a specialist since these tumors are so rare.
The treatment for germ cell cancers of the ovary depends
on the exact type and the stage of the cancer. Surgery
will reveal the stage and which organs should be removed.
Most women with germ cell cancers will also have chemotherapy.
Treatment for Stromal Cell Tumors
Most stromal cell tumors are confined to the ovary.
They are treated by removing the ovary with the tumor.
If the tumor returns, more surgery and chemotherapy
may also be used. Rarely, radiation therapy may be
used.
Clinical Trials
Studies of promising new treatments are known as clinical
trials. A clinical trial is done only when there is
some reason to believe that the new treatment may
be of value to the patient. Clinical trials are needed
in order to find new and better ways to treat cancer.
Treatments used in clinical trials are often found
to have real benefits. The main questions the researchers
want to answer are:
" Is this treatment helpful?
" Does it work better than the one we're now using?
" What side effects does it cause?
" Do the benefits outweigh the side effects?
" Which patients are most likely to find this treatment
helpful?
Clinical trials are carried out in steps called phases.
Each phase is designed to answer certain questions
Phase I clinical trials
look at the best way to give a new treatment and how
much of it can be given safely. The main purpose of
a phase I study is to test the safety of the new drug.
Phase II clinical trials
are designed to see if the drug works. Patients are
given the highest dose that doesn't cause serious
side effects and then watched closely to see if there
is an effect on the cancer.
Phase III clinical trials
compare the new treatment with standard treatment.
Large numbers of patients are divided into 2 groups.
The control group receives standard treatment and
the other group receives the new treatment. Everyone
is closely watched to see which treatment is more
effective. The study is stopped if the side effects
are too severe or if one group has much better results
than the other.
If you are in a clinical trial, you will have a team
of experts watching your progress very carefully.
However, there are some risks. No one knows in advance
if the treatment will work or exactly what side effects
will occur. That is what the study is designed to
discover. Keep in mind, though, that even standard
treatments have side effects.
Taking part in a clinical trial is completely up to
you. Even after joining a clinical trial, you are
free to leave the study at any time, for any reason.
Taking part in the study will not prevent you from
getting other medical care you may need.
Courtesy: www.cancer.org,
Please visit the website for further information |