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What is cervical cancer?
The cervix is the lower part of the uterus (womb). It is
sometimes called the uterine cervix. The body (upper part) of the
uterus is where a fetus grows. The cervix connects the body of the
uterus to the vagina (birth canal). The part of the cervix closest to
the body of the uterus is called the endocervix. The part next to the
vagina is the exocervix
(or ectocervix). The place where these 2 parts meet is
called the transformation
zone. Most cervical cancers start in the transformation
zone.
Cancer of the cervix (also known as cervical cancer) begins in
the cells lining the cervix. The 2 main types of cells lining the
cervix are squamous
cells and glandular
cells. Most cervical cancers
begin in those cells. These cells do not suddenly change into cancer.
Instead, the normal cells of the cervix gradually develop pre-cancerous
changes that turn into cancer. Doctors use several terms to describe
these pre-cancerous changes, including cervical intraepithelial
neoplasia (CIN), squamous intraepithelial lesion (SIL), and dysplasia.
Cervical cancers and cervical pre-cancers are classified by
how they look under a microscope. There are 2 main types of cervical
cancer: squamous cell
carcinoma and adenocarcinoma.
About 80% to 90% of
cervical cancers are squamous cell carcinomas. These cancers start in
the squamous cells that cover the surface of the exocervix. Under the
microscope, this type of cancer is made up of cells that are like
squamous cells. Squamous cell carcinomas most often begin where the
exocervix joins the endocervix.
The remaining 10% to 20% of cervical cancers are
adenocarcinomas. Adenocarcinomas are becoming more common in women born
in the last 20 to 30 years. Cervical adenocarcinoma develops from the
mucus-producing gland cells of the endocervix. Less commonly, cervical
cancers have features of both squamous cell carcinomas and
adenocarcinomas. These are called adenosquamous carcinomas or mixed
carcinomas.
Although cervical cancers start from cells with pre-cancerous
changes (pre-cancers), only some of the women with pre-cancers of the
cervix will develop cancer. The change from pre-cancer to cancer
usually takes several years - but it can happen in less than a year.
For most women, pre-cancerous cells will remain unchanged and go away
without any treatment. Still, in some cases pre-cancers turn into true
(invasive) cancers. Treating all precancers can prevent almost all true
cancers. Pre-cancerous changes and specific types of treatment for
precancers are discussed in the section, "Can Cervical Cancer Be
Prevented?"
Importance of cervical cancer screening
The goal of screening for cervical cancer is to find cervix
cell changes and early cervical cancers before they cause symptoms.
Screening
refers to the use of tests and exams to find a disease, such
as cancer, in people who do not have any symptoms. Early detection
means applying a strategy that results in an earlier diagnosis of
cervical cancer than otherwise might have occurred. Screening tests
offer the best opportunity to detect cervical cancer at an early stage
when successful treatment is likely. Screening can also actually
prevent most cervical cancers by finding abnormal cervix cell changes
(pre-cancers) so that they can be treated before they have a chance to
turn into a cervical cancer.
Cancer of the cervix may be prevented or detected early by
regular Pap tests. If it is detected early, cervical cancer is one of
the most successfully treatable cancers. In the United States, the
cervical cancer death rate declined by 74% between 1955 and 1992, in
large part due to the effectiveness of Pap smear screening. The death
rate continues to decline each year.
Despite the recognized benefits of Pap test screening, not all
American women take advantage of it. As of the year 2000, slightly over
80% of women had had a Pap test in the previous 3 years. Asian-American
women, recent immigrants, women without health insurance, and women
with fewer years of education were less likely to have had regular Pap
tests.
Between 60% and 80% of American women with newly diagnosed
invasive cervical cancer have not had a Pap smear in the past 5 years.
Many of these women have never had a Pap test.
Cervical cancer deaths are higher in populations around the
world where women do not have routine Pap tests. In fact, cervical
cancer is the major cause of cancer deaths in women in many developing
countries. These cases are usually diagnosed at an invasive late stage,
rather than as pre-cancers or early cancers.
What are the risk factors for cervical
cancer?
A risk factor is anything that changes your chance of getting
a disease such as cancer. Different cancers have different risk
factors. For example, exposing skin to strong sunlight is a risk factor
for skin cancer. Smoking is a risk factor for many cancers. But having
a risk factor, or even several, does not mean that you will get the
disease.
Several risk factors increase your chance of getting cervical
cancer. Women without any of these risk factors rarely develop cervical
cancer. Although these factors increase the odds of getting cervical
cancer, many women with these risk factors do not develop this disease.
When a woman develops cervical cancer or pre-cancerous changes of the
cervix, it is not possible to say with certainty that a particular risk
factor was the cause.
In thinking about the following risk factors, it helps to
focus on those that you can change or avoid (like smoking or human
papillomavirus infection), rather than those that you cannot (such as
your age and family history). It is still important, though, to know
about risk factors that cannot be changed, because it's even more
important for women who have these factors to get regular Pap tests to
detect cervical cancer early.
Cervical cancer risk factors include:
Human papilloma
virus infection
The most important risk factor for cervical cancer is
infection by the human papilloma virus (HPV). HPV is a group of more
than 100 related viruses. They are called papilloma viruses because
some of them can cause a type of growth called a papilloma. Papillomas,
more commonly called warts, are benign tumors - they are not cancers.
HPV is passed from one person to another during skin-to-skin contact.
HPV can be spread during sex - including vaginal intercourse, anal
intercourse, and even during oral sex.
Doctors believe that women must have been infected by HPV
before they will develop cervical cancer. Certain types of HPV are
called "high-risk" or “carcinogenic” types of HPV
because they are often the cause of cancer of the cervix. These types
include HPV 16, HPV 18, HPV 31, HPV 33, and HPV 45, as well as some
others. About 70% of all cervical cancers are caused by HPV 16 and 18.
Different types of HPV cause warts on different parts of the
body. Some types cause common warts on the hands and feet. Other types
tend to cause warts on the lips or tongue.
Still other types of HPV may cause warts to appear on or
around the female and male genital organs and in the anal area. These
warts may barely be visible or they may be several inches across. The
medical term for genital warts is condyloma
acuminatum. Two types of
HPV, HPV 6 and HPV 11, cause most cases of genital warts. These 2 types
are seldom linked to cervical cancer; and so are called "low-risk"
types of HPV. Other sexually transmitted HPVs have been linked with
genital and anal cancers in both men and women.
Many women become infected with HPV, but very few will ever
develop cervical cancer. In most cases the body's immune system fights
off the virus, and the infection goes away without any treatment. In
some cases, for reasons that we don't understand, the infection
persists, which can cause cervical cancer. Although there is currently
no cure for infection with HPV, there are ways to treat the warts and
abnormal cell growth that HPV causes.
The Pap test looks for changes in cervical cells caused by
HPV infection. Newer tests look for HPV infections by finding genes
(DNA) from HPV in the cells. Some doctors use the test for HPV to help
decide what to do when a woman has a mildly abnormal Pap test result.
If the test finds a high-risk type of HPV, it may mean she will need a
full evaluation with a colposcopy procedure.
HPV infections occur mainly in young women and are less common
in women over 30. The reason for this is not clear. Uncircumcised men
are thought to be more likely to have the virus and be able to pass it
on to someone else. HPV infection can be present for years without any
symptoms. Even when someone doesn't have visible warts (or any other
symptom), he (or she) can still be infected with HPV and pass the virus
to somebody else.
Condoms ("rubbers") do offer some protection against HPV, but
they cannot completely protect against infection. This is because
condoms don't cover every possible HPV-infected area of the body, such
as skin of the genital or anal area. HPV can still be passed from one
person to another by skin-to-skin contact with an HPV-infected area of
the body that is not covered by the condom. Still, it is important to
use condoms to protect against AIDS and other sexually transmitted
illnesses that are passed on through some body fluids.
Vaccines have been developed that may protect against
infection with some types of HPV. By preventing HPV infection, these
vaccines may reduce cervical cancer rates in the future. Right now,
there is an HPV vaccine that has been approved for use in the United
.States. by the Food and Drug Administration (FDA). This vaccine is
called Gardasil®, and it protects
against HPV types 6, 11, 16,
and 18. More HPV vaccines are being developed and tested. Giardasil is
described in more detail in the section, “Can Cervical Cancer
Be Prevented?” Other vaccines are also in development.
Although scientists believe that it is necessary to have had
HPV for cervical cancer to develop, most women with this virus do not
develop cancer. Doctors believe that other factors must come into play
for cancer to develop. Some of these known factors are listed below.
Smoking
Women who smoke are about twice as likely as non-smokers to
get cervical cancer. Smoking exposes the body to many cancer-causing
chemicals that affect more than the lungs. These harmful substances are
absorbed by the lungs and carried in the bloodstream throughout the
body. Tobacco by-products have been found in the cervical mucus of
women who smoke. Researchers believe that these substances damage the
DNA of cervix cells and may contribute to the development of cervical
cancer.
Immunosuppression
Human immunodeficiency virus (HIV) is the virus that causes
acquired immunodeficiency syndrome (AIDS). HIV damages the body's
immune system and seems to make women more likely to become infected
with HPV. This may be what increases the risk of cervical cancer in
women with AIDS. Scientists believe that the immune system is important
in destroying cancer cells and slowing their growth and spread. In
women infected with HIV, a cervical pre-cancer might develop into an
invasive cancer faster than it normally would.
Chlamydia
infection
Chlamydia is a relatively common kind of bacteria that can
infect the reproductive system. It is spread by sexual contact. Some
studies have seen a higher risk of cervical cancer in women whose blood
test results show past or current chlamydia infection (compared with
women with normal test results). Infection with chlamydia often causes
no symptoms in women. A woman may not know that she is infected at all
unless she is tested for chlamydia when she gets her pelvic exam.
Long-term chlamydia infection can cause pelvic inflammation, leading to
infertility.
Diet
Women with diets low in fruits and vegetables may be at
increased risk for cervical cancer. Also, overweight women are more
likely to develop this cancer.
Oral
contraceptives (birth control pills)
There is evidence that taking oral contraceptives (OCs) for a
long time increases the risk of cancer of the cervix. Research suggests
that the risk of cervical cancer goes up the longer a woman takes OCs,
but the risk goes back down again after the OCs are stopped. In a
recent study, the risk of cervical cancer was doubled in women who took
birth control pills longer than 5 years, but the risk returned to
normal 10 years after they were stopped.
The American Cancer Society believes that a woman and her
doctor should discuss whether the benefits of using OCs outweigh this
very slight potential risk. A woman with multiple sexual partners
should use condoms to lower her risk of sexually transmitted infections
no matter what other form of contraception she uses.
Multiple
pregnancies
Women who have had many full-term pregnancies have an
increased risk of developing cervical cancer. No one really knows why
this is true. One theory is this may be because some of the women may
have been exposed more to HPV through un-protected sexual contact.
Also, studies have pointed to hormonal changes during pregnancy as
possibly making women more susceptible to HPV infection or cancer
growth. Another thought is that the immune system of pregnant women
might be weaker, allowing for HPV infection and cancer growth.
Low
socioeconomic status
Poverty is also a risk factor for cervical cancer. Many women
with low incomes do not have ready access to adequate health care
services, including Pap tests. This means they may not get screened or
treated for pre-cancerous cervical disease.
Diethylstilbestrol
(DES)
DES is a hormonal drug that was given to some women to prevent
miscarriage during the years between 1940 and 1971. Women whose mothers
took DES when pregnant with them are often called "DES daughters."
These women develop clear cell adenocarcinoma of the vagina or cervix
more often than would normally be expected. There is about 1 case of
this type of cancer in every 1,000 women whose mother took DES during
their pregnancy. This means that about 99.9% of "DES daughters" do not
develop these cancers.
DES-related clear cell adenocarcinoma is more common in the
vagina than the cervix. The risk appears to be greatest in women whose
mothers took the drug during their first 16 weeks of pregnancy. The
average age of women when they are diagnosed with DES-related
clear-cell adenocarcinoma is 19 years. Since the use of DES during
pregnancy was stopped by the FDA in 1971, even the youngest DES
daughters are older than 35 - past the age of highest risk. Still,
there is no age cut-off when these women are safe from DES-related
cancer - doctors do not know exactly how long women will remain at
risk.
DES daughters may also be at increased risk of developing
pre-cancerous changes of cervical squamous cells and squamous cell
cancer of the cervix. These pre-cancers and cancers seem to be linked
to HPV.
Although DES daughters have an increased risk of developing
clear cell carcinomas women don’t have to be exposed to DES
for clear cell carcinoma to develop. In fact, women were diagnosed with
the disease before DES was invented.
Family history
of cervical cancer
Cervical cancer may run in some families. If a
woman’s mother or sister had cervical cancer, her chances of
developing the disease are 2 to 3 times higher than normal. Some
researchers suspect this familial tendency is caused by an inherited
condition that makes some women less able to fight off HPV infection
than others.
Signs and symptoms of cervical cancer
Women with early cervical cancers and pre-cancers usually have
no symptoms. Symptoms often do not begin until a pre-cancer becomes a
"true" invasive cancer and grows into nearby tissue. When this happens,
the most common symptoms are:
- Abnormal vaginal bleeding, such as bleeding after
sex (vaginal intercourse), bleeding after menopause, bleeding and
spotting between periods, and having (menstrual) periods that are
longer or heavier than usual. Bleeding after douching, or after a
pelvic exam is a common symptom of cervical cancer but not pre-cancer.
- An unusual discharge from the vagina - the
discharge may contain some blood and may occur between your periods or
after menopause.
- Pain during sex (vaginal intercourse).
These signs and symptoms can also be caused by conditions
other than cervical cancer. For example, an infection can cause pain
or, rarely, bleeding. Still, if you have any of these problems, you
should see your health care professional right away - even if you have
been getting regular Pap tests. If it is an infection, it will need to
be treated. If it is cancer, ignoring symptoms may allow it to progress
to a more advanced stage and lower your chance for effective treatment.
Even better, don't wait for symptoms to appear. Have a regular
Pap test and pelvic exam.
Can cervical cancer be prevented?
Since the most common form of cervical cancer starts with
pre-cancerous changes, there are 2 ways to stop this disease from
developing. The first way is to prevent the pre-cancers, and the second
is to find and treat pre-cancers before they become true cancers.
Things to do to prevent pre-cancers
Avoid being
exposed to HPV
You can prevent most pre-cancers of the cervix by avoiding
exposure to HPV. Certain types of sexual behavior increase a woman's
risk of getting HPV infection, such as:
- having sex at an early age
- having many sexual partners
- having a partner who has had many sex partners
- having sex with uncircumcised males
Delay sex
Waiting to have sex until you are older can help you avoid
HPV. It also helps to limit your number of sexual partners and to avoid
having sex with someone who has had many other sexual partners.
Remember that someone can have HPV for years yet have no symptoms - it
does not always cause warts or any other symptoms. Someone can have the
virus and pass it on without knowing it.
Use condoms
Condoms provide some protection against HPV. One study found
that when condoms are used correctly they can lower the HPV infection
rate by about 70% - if they are used every time sex occurs. Condoms
cannot protect completely because they don't cover every possible
HPV-infected area of the body, such as skin of the genital or anal
area. Still, condoms provide some protection against HPV, and they also
protect against HIV and some other sexually transmitted diseases.
Don’t
smoke
Not smoking is another important way to reduce the risk of
cervical pre-cancer and cancer.
Get vaccinated
Vaccines have been developed that can protect women from HPV
infections. So far, a vaccine that protects against HPV types 6, 11, 16
and 18 (Gardasil®) and one that protects
against types 16 and
18 (Cervarix®) have been studied.
Gardasil has been approved for use in this country by the FDA.
It requires a series of 3 injections over a 6-month period. The second
injection is given 2 months after the first one, and the third is given
4 months after the second. Side effects are said to be mild. The most
common one is short-term redness, swelling, and soreness at the
injection site. In clinical trials, Gardasil prevented genital warts
caused by HPV types 6 and 11 and prevented pre-cancers and cancers of
the cervix caused by HPV types 16 and 18. This vaccine only works to
prevent HPV infection -- it will not treat an infection that is already
there.
To be most effective, the HPV vaccine should be given before a
person starts having sex. The Federal Advisory Committee on
Immunization Practices (ACIP) has recommended that the vaccine be given
routinely to females aged 11 to 12. It can be given to younger females
(as young as age 9) at the discretion of doctors. ACIP also recommended
women ages 13 to 26 who have not yet been vaccinated get "catch-up"
vaccinations.
The American Cancer Society also recommends that the vaccine
be routinely given to females aged 11 to 12 and as early as age 9 years
at the discretion of doctors. The Society also agrees that
“catch-up” vaccinations should be given to females
aged 13 to 18. The independent panel making the Society recommendations
found that there was not enough proof of benefit to recommend catch-up
vaccination for every woman aged 19 to 26 years. As a result, the
American Cancer Society recommends that women aged 19 to 26 talk with
their health care provider about the risk of previous HPV exposure and
potential benefit from vaccination before deciding to get vaccinated.
Research is now being done on using Gardasil in older women and in
males. The American Cancer Society guideline focuses on Gardasil at
this time. As new information on Cervarix, Gardasil, and other new
products becomes available, these guidelines will be updated.
Gardasil is expensive - the vaccine series costs around $360
(not including any doctor’s fee or the cost of giving the
injections). It should be covered by most medical insurance plans (if
given according to ACIP guidelines). It should also be covered by
government programs that pay for vaccinations in children under 18.
Because this vaccine costs so much, you may want to check your coverage
with your insurance company first.
It is important to realize that the vaccine doesn’t
protect against all cancer-causing types of HPV, so routine Pap tests
are still necessary. One other benefit of the vaccine is that it
protects against the 2 viruses that cause 90% of genital warts.
For more information on the vaccine and HPV, please see our
document, Human Papilloma Virus: Questions and Answers.
Finding pre-cancerous changes
One way to prevent cervix cancer is to have testing
(screening) to find pre-cancers before they can turn into invasive
cancer. The Pap test (or Pap smear) is the most common way to do this.
If a pre-cancer is found, it can be treated, stopping cervical cancer
before it really starts. Since the HPV vaccine doesn't protect against
all of the HPV types that can cause cancer of the cervix, it cannot
prevent all cases of cervical cancer. This is why it is very important
that women continue to have Pap tests, even after they’ve
been vaccinated. Most invasive cervical cancers are found in women who
have not had regular Pap tests.
The American Cancer Society recommends the following
guidelines for early detection:
- All women should begin cervical cancer testing
(screening) about 3 years after they start having sex (vaginal
intercourse). A woman who waits until she is over 18 to have sex should
start screening no later than age 21. A regular Pap test should be done
every year. If the newer liquid-based Pap test is used, testing can be
done every 2 years.
- Beginning at age 30, women who have had 3 normal
Pap test results in a row may be tested less often - every 2 to 3
years. Either the conventional (regular) Pap test or the liquid-based
Pap test can be used.
- Another reasonable option for women over 30 is to
get tested every 3 years (but not more frequently) with either the
regular Pap test or liquid-based Pap test, plus the HPV DNA test (see
below for more information on this test).
- Women who have certain risk factors should continue
getting tested yearly. This includes women exposed to
diethylstilbestrol (DES) before birth and those with a weakened immune
system (from HIV infection, organ transplant, chemotherapy, or chronic
steroid use).
- Women who have had a total hysterectomy (removal of
the uterus and cervix) may choose to stop having cervical cancer
testing, unless the surgery was done as a treatment for cervical cancer
or pre-cancer. Women who have had a hysterectomy without removal of the
cervix (simple hysterectomy) need to continue cervical cancer
screening, and should continue to follow the guidelines above.
- Women 70 years of age or older who have had 3 or
more normal Pap tests in a row and no abnormal Pap test results in the
last 10 years may choose to stop having cervical cancer testing. Women
with a history of cervical cancer, DES exposure before birth, HIV
infection, or a weakened immune system should continue to have testing
as long as they are in good health.
Some women believe that they can stop having Pap tests once
they have stopped having children. This is not correct. They should
continue to follow American Cancer Society guidelines.
The Papanicolaou (Pap) test
The Pap test (Pap smear) is the main screening test for
cervical cancer and pre-cancerous changes.
Although the Pap test has been more successful than any other
screening test in preventing a cancer, it is not perfect. One of the
limitations of the Pap test is that it needs to be examined by humans,
so an accurate analysis of the hundreds of thousands of cells in each
sample is not always possible. Engineers, scientists, and doctors are
working together to improve this test. Because some abnormalities may
be missed (even when samples are looked at in the best laboratories),
it is not a good idea to have this test less often than American Cancer
Society guidelines recommend.
Pelvic exam versus Pap test
Many people confuse pelvic exams with Pap tests. The pelvic
exam is part of a woman's routine health care. During a pelvic exam,
the doctor looks at and feels the reproductive organs, including the
uterus and the ovaries and do tests for sexually transmitted disease.
Pap tests are often done during pelvic exams, but you can have a pelvic
exam without having a Pap test. A pelvic exam without a Pap test will
not help find cervical cancer at an early stage or find abnormal cells
of the cervix.
The Pap test is often done at the start of the pelvic exam,
after the speculum is placed. To do a Pap test, the doctor must remove
cells from the cervix by gently scraping or brushing with a special
instrument. Pelvic exams may help find other types of cancers and
reproductive problems, but only Pap tests give information on early
cervical cancer or precancers.
How the Pap test is done
Cytology is the branch of science that deals with the
structure and function of cells. It also refers to tests to diagnose
cancer by looking at cells under the microscope. The Pap test (or Pap
smear) is a procedure used to collect cells from the cervix for
cervical cytology testing.
The health care professional first places a speculum inside
the vagina. The speculum is a metal or plastic instrument that keeps
the vagina open so that the cervix can be seen clearly. Next, using a
small spatula, a sample of cells and mucus is lightly scraped from the
exocervix (the surface of the cervix that is closest to the vagina). A
small brush or a cotton-tipped swab is then used to take a sample from
the endocervix (the inside part of the cervix that is closest to the
body of the uterus). There are 2 main ways to prepare the cell samples
so that they can be examined under a microscope in the laboratory.
- Conventional
cytology: The first way is to smear the sample
directly onto a glass microscope slide, which is then sent to the
laboratory. For about 50 years, all cervical cytology samples were
handled this way. This method works quite well and is relatively
inexpensive, but it does have some drawbacks. One problem with this
method is that the cells smeared onto the slide are sometimes piled up
on each other, making it hard to see the cells at the bottom of the
pile. Also, white blood cells (pus), increased mucus, yeast cells, or
bacteria from infection or inflammation can hide the cervical cells.
Another problem with direct smears is that if the slides are not
treated (with a preservative) right away, the cells can dry out. This
can make it difficult to tell if there is something wrong with the
cells. If the cervical cells cannot be seen well (because of any of
these problems), the Pap smear may need to be done again.
- Liquid based
cytology: Another method is to put the sample
of cells from the cervix into a special preservative liquid (instead of
putting them on a slide directly). Technicians use special lab
instruments that spread the cells in the liquid onto glass slides to
look at under the microscope. This method is called liquid-based
cytology, or a liquid-based Pap test. The liquid helps remove some of
the mucus, bacteria, yeast, and pus cells in a sample. It also allows
the cervical cells to be spread more evenly on the slide and keeps them
from drying out and distorting. Cells kept in the liquid can also be
tested for HPV. Using liquid-based testing reduces the chance that the
Pap test will need to be repeated, but it does not seem to find more
pre-cancers than a regular Pap test. This method, also known by brand
names ThinPrep® or AutoCyte®,
is more expensive than a
usual Pap test.
Another way to improve the Pap test is by using computerized
instruments that can spot abnormal cells in Pap tests. The
AutoPap® instrument has been approved by
the FDA to read Pap
tests first (instead of them being examined by a technologist). It is
also approved by the FDA for rechecking Pap test results that were read
as normal by technologists. Any smear identified as abnormal by the
AutoPap® would then be reviewed by a
doctor or a technologist.
Computerized instruments can find abnormal cells that
technologists sometimes miss. Most of the abnormal cells found in this
way are in rather early stages, such as atypical squamous cells (ASCs),
but sometimes high-grade abnormalities missed by human testing can be
found. Scientists do not know yet whether the instrument can find
enough high-grade abnormalities missed by human testing to have a real
impact on preventing invasive cervical cancers. Automated testing also
increases the cost of the cervical cytology testing.
For now, the best way to detect cervical cancer early is to
make certain that all women are tested according to American Cancer
Society guidelines. Unfortunately, many of the women most at risk for
cervical cancer are not being tested often enough or at all.
Making your Pap tests more accurate
You can do several things to make your Pap test as accurate as
possible:
- Try not to schedule an appointment for a time
during your menstrual period. The best time is at least 5 days after
your menstrual period stops.
- Don't use tampons,
birth-control foams, jellies or other vaginal creams for 2 to 3 days
before the test.
- Don't douche for 2 to 3 days before the
test.
- Don't have sexual intercourse for 2 days
before the test.
Is there a "home" Pap test?
Doctors have been trying to find ways to get more women
involved in cervical cancer screening. Some have proposed methods that
would allow women to obtain cervical cell samples at home. For this
test, a woman would collect cervical cells herself by inserting a small
plastic applicator into the vagina and moving it around on the cervix.
This would be placed in a special container to preserve the cells. This
type of approach has been used to check for sexually transmitted
diseases in poorer countries, and it has also been useful to check for
HPV infections. So far, however, no "home-based" Pap test has been
approved for use in the U.S. Currently, the American Cancer Society
does not recommend any "at home" Pap test.
How Pap test results are reported
The most widely used system for describing Pap test results is
the Bethesda System (TBS). This system has been revised twice since it
was developed in 1988 -- first in 1991 and, most recently, in 2001. The
information that follows is based on the 2001 version. There are 3 main
categories, some of which have sub-categories:
- negative for intraepithelial lesion or malignancy,
- epithelial cell abnormalities, and
- other malignant neoplasms.
Negative for
intraepithelial lesion or malignancy: This first
category means that no signs of cancer, precancerous changes, or other
significant abnormalities were found. Some specimens in this category
appear entirely normal. Others may have findings that are unrelated to
cervical cancer, such as signs of infection (with yeast, herpes, or
trichomonas, for example). Some cases may also show "reactive cellular
changes", which the way cervical cells respond to infection or other
irritation.
Epithelial cell
abnormalities: The second category, epithelial
cell abnormalities, means that the cells of the lining layer of the
cervix show changes that might be cancer or a pre-cancerous condition.
This category is divided into several groups for squamous cells and
glandular cells. The epithelial cell abnormalities for squamous cells
are:
Atypical squamous cells (ASCs):
This term is used when there
are cells that look abnormal, but it is not possible to tell (by
looking at the cells under a microscope) if this caused by infection,
irritation, or precancer. This group is further divided into 2 groups,
atypical squamous cells of uncertain significance (ASC-US) and atypical
squamous cells where high-grade squamous intraepithelial lesion (SIL)
can’t be excluded (ASC-H). Most of the time, cells labeled
ASC-US are not pre-cancer.. Some doctors will recommend repeating the
Pap test after several months. Some doctors use the HPV DNA test to
help them decide on the best treatment plan. If a woman with ASC-US is
infected with a high-risk type of HPV, doctors are more inclined to do
a colposcopy. The term ASC-H is used if a SIL is suspected. Colposcopy
is usually done in cases of ASC-H.
Squamous intraepithelial lesions
(SILs): These abnormalities
are subdivided into low-grade SIL and high-grade SIL. All patients with
this Pap test result should have colposcopy. High-grade SILs are less
likely than low-grade SILs to go away without treatment. They are also
more likely to eventually develop into cancer if they are not treated.
Treatment can cure all SILs and prevent true cancer from developing. A
Pap test cannot tell for certain whether a woman has a high- or
low-grade SIL. It merely flags the result as fitting into one of these
abnormal categories. All patients with a Pap test result of SIL should
have colposcopy. The need for treatment is based on the results of the
colposcopy. Since most SILs are positive for HPV, HPV testing is not
very helpful in deciding what to do for an SIL.
Squamous cell carcinoma:
This result means that the woman is
likely to have an invasive squamous cell cancer. Further testing will
be done to be sure of the diagnosis beforetreatment can be planned.
The Bethesda System also describes epithelial cell
abnormalities for glandular cells.
Adenocarcinoma:
Cancers of the glandular cells are called
adenocarcinomas. In some cases, the pathologist examining
the cells can
suggest whether the adenocarcinoma started in the endocervix, in the
uterus (endometrium), or elsewhere in the body.
Atypical glandular cells:
When the glandular cells do not look
normal, but have features that do not permit a clear decision as to
whether they are cancerous, the term used is atypical glandular cells
(AGCs). The patient will usually have more testing if her
cervical
cytology result shows atypical glandular cells.
Other malignant
neoplasms: This category refers to forms of
cancer that rarely affect the cervix, such as malignant melanoma,
sarcomas, and lymphoma.
Other methods of describing Pap test results have also been
used in the past.
The HPV DNA Test
As mentioned earlier, the most important risk factor for
developing cervical cancer is infection with HPV. Doctors can now test
for the types of HPV that are most likely to cause cervical cancer
("high-risk" or "carcinogenic" types) by looking
for pieces of their DNA in cervical cells. The test is done in a
similar way to the Pap test in terms of how the sample is collected,
and in some cases can even be done on the same sample.
The HPV DNA test can be used in 2 situations:
- The FDA recently approved the HPV gene test to be
used combination with the Pap test to screen for cervical cancer in
women over 30 years old (see American Cancer Society screening
guidelines above). It does not replace the Pap test.. Women in their
20s who are sexually active are much more likely (than older women) to
have an HPV infection that will go away on its own. For these younger
women, results of this test are not as significant and may be more
confusing. . For this reason, the HPV DNA test is not recommended as a
screening test in women under 30. For more information, see the
American Cancer Society documents, What
Every Woman Should Know About
Cervical Cancer and the Human Papilloma Virus and Thinking
About
Testing for HPV?
- The HPV DNA test is also used in women of any age
who have slightly abnormal Pap test results to find out if they might
need more testing or treatment. (see next section).
Other tests for women with abnormal cervical
cytology results
The Pap test is a screening test, not a diagnostic test - it
cannot tell for certain that cancer is present. An abnormal Pap test
result means that you will likely need to have other tests to find out
if a cancer or a pre-cancer is actually present. The tests that are
used include colposcopy (with biopsy) and endocervical scraping. These
tests are commonly used when the results of a Pap test are reported as
SIL, atypical glandular cells, or cancer. If a biopsy shows a
pre-cancer, doctors will take steps to keep an actual cancer from
developing.
Doctors are less certain about what to do when the Pap test
result shows atypical squamous cells. In deciding what to do, some
doctors take into account your previous Pap test results, whether you
have any cervical cancer risk factors, whether you have remembered to
have Pap tests done in the past, and whether the test result is ASC-H
or ASC-US. For ASC-H, many doctors will recommend colposcopy and
biopsy. For ASC-US some doctors will recommend colposcopy and biopsy if
a high-risk HPV DNA is detected, but others recommend repeating the Pap
test after several months.
Colposcopy
If you have certain symptoms that suggest cancer or if your
Pap test shows abnormal cells, you will need to have a test called
colposcopy. In this procedure you will lie on the exam table as you do
with a pelvic exam. A speculum will be placed in the vagina to help the
doctor see the cervix. The doctor will use the colposcope to examine
the cervix. The colposcope is an instrument with magnifying lenses
(like binoculars), that lets the doctor see the surface of the cervix
closely and clearly. The doctor may "treat" your cervix with a weak
solution of acetic acid (similar to vinegar) to make any abnormal areas
easier to see.
Colposcopy is not painful, has no side effects, and can be
done safely even if you are pregnant. If an abnormal area is seen on
the cervix, a biopsy will be done. For a biopsy, small piece of tissue
is removed from the area that looks abnormal. The sample is sent to a
pathologist to look at under a microscope. A biopsy is the only way to
tell for certain whether an abnormal area is a pre-cancer, a true
cancer, or neither.
Cervical biopsies
Several types of biopsies are used to diagnose cervical
precancers and cancers. If the biopsy can completely remove all of the
abnormal tissue, it may be the only treatment needed. In some
situations, additional treatment of precancers or cancers is needed.
Colposcopic biopsy:
For this type of biopsy, a doctor or other
health care professional first examines the cervix with a colposcope to
find the abnormal areas. Using a biopsy forceps, the doctor will remove
a small (about 1/8-inch) section of the abnormal area on the surface of
the cervix. The biopsy procedure may cause mild cramping or brief pain,
and you may have light bleeding afterward. A local anesthetic is
sometimes used to numb the cervix before the biopsy.
Endocervical curettage
(endocervical scraping): The colposcope
does not help the doctor see into the endocervix. The endocervix will
have to be scraped to see if it is affected by pre-cancer or cancer.
This procedure is usually done at the same time as the colposcopic
biopsy. A local anesthetic may be used to numb the cervix. Then, a
narrow instrument (called a curette)
is inserted into the endocervical
canal (the passage between the outer part of the cervix and the inner
part of the uterus). Some of the tissue that is lining the endocervical
canal is removed by scraping with the curette. This tissue sample is
sent to the lab for examination. After this procedure, patients may
feel a cramping pain, and they may also have some light bleeding.
Cone biopsy:
In this procedure, also known as conization,
the
doctor removes a cone-shaped piece of tissue from the cervix. The base
of the cone is formed by the exocervix (outer part of the cervix), and
the point or apex of the cone is from the endocervical canal. The
transformation zone (the border between the exocervix and endocervix)
is contained within the cone. This is the area of the cervix where
pre-cancers and cancers are most likely to develop. The cone biopsy can
be used as a treatment to completely remove many pre-cancers and some
very early cancers. Having a cone biopsy will not keep most women from
getting pregnant, but if the biopsy removes large amount of tissue
these women may have a higher risk of giving birth prematurely.
There are 2 methods commonly used for cone biopsies: the loop
electrosurgical excision procedure (LEEP; also called large loop
excision of the transformation zone [LLETZ]) and the cold knife cone
biopsy.
- LEEP (LLETZ):
With this method, the tissue is
removed with a thin wire loop that is heated by electrical current and
acts as a scalpel. For this procedure, a local anesthetic is used, and
it can be done in your doctor's office. It can take as little as 10
minutes. You may have mild cramping during and after the procedure, and
mild to moderate bleeding may persist for several weeks.
- Cold knife
cone biopsy: This method uses a surgical
scalpel or a laser instead of a heated wire to remove tissue. It
requires general anesthesia (you are asleep during the operation) and
is done in a hospital, but no overnight stay is needed. After the
procedure, cramping and some bleeding may persist for a few weeks.
How biopsy
results are reported: The terms for reporting
biopsy results are slightly different from the Bethesda System for
reporting Pap test results. Pre-cancerous changes are called "cervical
intraepithelial neoplasia" (CIN) or, rarely, "dysplasia," instead of
"squamous intraepithelial lesion" (SIL). The terms for reporting
cancers ("squamous cell carcinoma" and "adenocarcinoma") are the same.
How women with abnormal Pap test results are
treated to
prevent cervical cancers from developing
If an abnormal area is seen during the colposcopy, your doctor
will be able to remove it with LEEP (LLETZ procedure). Other options
include a cold knife cone biopsy and destroying the abnormal cells with
cryosurgery or laser surgery.
During cryosurgery,
the doctor uses a metal probe cooled with
liquid nitrogen to kill the abnormal cells by freezing them.
In laser
surgery, the doctor uses a focused beam of
high-energy light to vaporize (burn off) the abnormal tissue. This is
done through the vagina, with local anesthesia.
Both cryosurgery and laser surgery can be done in a doctor's
office or clinic. After treatment, you may have alot of watery brown
discharge for a few weeks.
These treatments are almost always effective in destroying
pre-cancers and preventing them from developing into true cancers. You
will need follow-up exams to make sure that the abnormality does not
come back. If it does, the treatments can be repeated.
Cervical cancer prevention and screening:
Financial issues
Financial issues can play an important role in whether or not
women are screened for cervical cancer. Women with lower incomes and
those without health insurance are less likely to be screened.
Many states ensure that private insurance companies, Medicaid,
and public employee health plans provide coverage and reimbursement for
Pap smear screening tests. The ACS supports such coverage assurances,
because they remove financial barriers for women who have health
insurance, but whose insurance plans previously did not cover Pap
smears.
Other programs are also available to help provide financial
assistance for women with lower incomes and those without insurance.
State efforts to ensure coverage of cervical
cancer screening
for private health insurance
Twenty-six states and the District of Columbia now require
private health insurers to cover annual cervical cancer screening
services (see table).
A few states have also enacted laws specifically requiring
managed care organizations such as health maintenance organizations
(HMOs) and preferred provider organizations (PPOs) to cover cervical
cancer screening. Some states have ensured that public employee health
benefit plans cover cervical cancer screening. While Maryland does not
have a statewide benefit for cervical cancer screening, they do have a
unique law requiring hospitals to offer a Pap test to adult female
inpatients. Nebraska has a law that requires the Department of Health
to contract with health clinics of American Indian tribes to cover
cervical cancer detection services. Individual state laws vary widely.
Ask your health care provider what coverage is mandatory in your state
States With Laws
Assuring Coverage of Cervical Cancer
Screening (as of December 2006)
| State |
Private
Insurance |
Other |
| Alaska |
Annual Pap test for persons age 18 and over |
Copay, deductibles, and/or co-insurance may apply
|
| California |
Annual Pap test, pelvic exam, and HPV testing
Need referral for patient's health care provider |
Copay, deductibles and/or co-insurance may apply
|
| Delaware |
Annual Pap test for persons age 18 and over |
Copay, deductibles and/or co-insurance may apply
|
| District of Columbia |
Annual Pap test
More frequent tests if recommended by a physician |
|
| Georgia |
Annual Pap test
Need referral of patient's health care provider
More frequent tests if recommended by a physician |
Copay, deductibles and/or co-insurance may apply
|
| Illinois |
Annual Pap test |
|
| Kansas |
Annual Pap test
Need referral of patient's health care provider |
Copay, deductibles and/or co-insurance may apply
|
| Louisiana |
Annual Pap test |
|
| Maine |
Annual Pap test and pelvic exam
Need referral of patient's health care provider
|
|
| Maryland |
Covers HPV testing only, according to ACOG Guidelines
(see below) |
Copay, deductibles and/or co-insurance may apply |
| Massachusetts |
Annual Pap test for persons age 18 and over |
|
| Minnesota |
Cover Pap test when ordered by doctor, according to
standard practice |
|
| Missouri |
Cover Pap test and pelvic exam according to ACS
guidelines (see below) |
Copay, deductibles and/or co-insurance may apply
|
| Nevada |
Annual Pap test for persons age 18 and over |
|
| New Jersey |
Cover Pap test every 2 years for persons 20 and over
More frequent testing if recommended by a doctor
Need referral of patient's health care provider |
Certain specified HMOs must only offer and not provide
coverage
|
| New Mexico |
Cover Pap test, pelvic exam, and HPV
testing for persons age 18 and over
Medical standards determine how often testing should be done
Need referral of patient's health care provider |
Copay, deductibles and/or co-insurance may apply
|
| New York |
Annual Pap test and pelvic exam for persons 18
and over |
Copay, deductibles and/or co-insurance may apply
|
| North Carolina |
Cover Pap test and HPV testing according to
ACS guidelines (see below) or those established by the NC Advisory
Committee on
Cancer Coordination and Control |
Copay, deductibles and/or co-insurance may apply |
| Ohio |
Cover Pap test |
Public employee plan: specified coverage |
| Oregon |
Annual Pap test and HPV testing for persons age 18-64
More frequent testing if recommended by a doctor |
|
| Pennsylvania |
Cover Pap test and pelvic exam according to ACOG
Guidelines (see below) |
|
| Rhode Island |
Cover Pap test according to ACS guidelines (below) |
|
| South Carolina |
Annual Pap test
More frequent testing if recommended by a doctor
Need referral of pateint's health care provider |
Copay, deductibles and/or co-insurance may apply
|
| Texas |
Annual Pap test and HPV test when done at the same
time, for persons age 18 and over, according to ACOG (or similar
national organization) Guidelines (see below) |
|
| Virginia |
Annual Pap test |
|
| West Virginia |
Annual Pap test and HPV testing for persons age 18 and
over, according to ACOG Guidelines or USPSTF Recommendations (see below) |
Copay, deductibles and/or co-insurance may apply
|
| Wyoming |
Cover Pap test and pelvic exam |
Co-insurance may apply
|
ACOG
(American College of Obstetricians and Gynecologists)
Guidelines: Cervical cancer screening should begin within
3 years after
first vaginal intercourse, or by age 21, whichever comes first.
Guidelines for subsequent screening differ based on age, type of
screening test, and prior test results.
ACS
(American Cancer Society) Guidelines: Cervical cancer
screening should begin about 3 years after a woman begins having
vaginal intercourse, but no later than 21 years of age. Guidelines
for
subsequent screening differ based on age, type of screening test, and
prior test results.
USPSTF
(United States Preventative Services Task Force)
Recommendations: The USPSTF strongly recommends screening
for cervical
cancer in women who have been sexually active and recommends against
routinely screening women older than age 65 or women who have had a
total hysterectomy for benign disease.
Source: National Cancer Institute: State Cancer Legislative
Database Program, Bethesda, MD. 2006.
Self-Insured Plans
ERISA, or self-insured plans, are not regulated at the state
level and therefore women in these plans do not necessarily get
cervical cancer screening benefits, even if there are state laws
ensuring coverage for such benefits. Self-insured plans are typically
large employers. Women who have self-insured based health insurance
should check with their health plans to see what cervical cancer
screening services are offered.
Medicaid
By statute or agency policy, Medicaid or public assistance
programs in all 50 states and the District of Columbia cover screening
for cervical cancer either routinely or upon a doctor’s
recommendation. This coverage may or may not conform to American Cancer
Society guidelines. Please check with your state Medicaid office to
learn more about what services are provided for cervical cancer
screening.
Medicare
Medicare provides coverage for a screening Pap test, pelvic
exam, and a clinical breast exam every 2 years for Medicare
beneficiaries. And if a woman is of childbearing age and has had an
abnormal Pap test in the previous 3 years, or is at high risk for
cervical or vaginal cancer, she would be eligible under Medicare to be
covered for screening every year. The deductible is waived for this
screening.
National Breast and Cervical Cancer Early
Detection Program
All states are making cervical cancer screening more available
to medically underserved women through the National Breast and Cervical
Cancer Early Detection Program (NBCCEDP). This program provides breast
and cervical cancer screening to women without health insurance for
free or at very little cost. The NBCCEDP attempts to reach as many
women in medically underserved communities as possible, including older
women, women without health insurance and women who are members of
racial and ethnic minorities.
Though the program is administered within each state, the
Centers for Disease Control and Prevention (CDC) provides matching
funds and support to each state program.
Since 1991, the program has provided over 4.5 million
screening exams to underserved women, diagnosed over 17,000 breast
cancers, over 61,000 pre-cancerous cervical lesions, and over 1,100
cervical cancers. These accomplishments demonstrate a truly nationwide
effort. However, due to limited resources, only about 15% of all
eligible women are served nationwide.
Each state's Department of Health will have
information on how to contact the nearest program participant. For more
information on this program, you can also contact the CDC at
1-800-CDC-INFO (1-800-232-4636) or on the Web at
www.cdc.gov/cancer/nbccedp.
If cervical cancer is detected during screening in this
program, most states can now extend Medicaid benefits to these women to
cover the costs of treatment.
HPV vaccine costs
It is expected that insurance plans will cover the cost of the
HPV vaccine in accordance with the Federal Advisory Committee on
Immunization Practices (ACIP) recommendations. ACIP has also
recommended that the HPV vaccine be included in the federal Vaccine for
Children (VFC) entitlement program, which covers vaccine costs for
children and teens who do not have insurance or who are underinsured.
Additional resources
More information from your American Cancer
Society
The following information may also be helpful to you. These
materials may be ordered from our toll-free number, 1-800-ACS-2345
(1-800-227-2345).
American
Cancer Society Recommendations For Human
Papillomavirus (HPV) Vaccine Use To Prevent Cervical Cancer And
Pre-Cancers
Cervical
Cancer (also available in Spanish)
Human
Papilloma Virus (HPV) Vaccines -- Frequently Asked
Questions (also available in Spanish)
Thinking
About Testing for HPV? (also available in Spanish)
What
Every Woman Should Know About Cervical Cancer and the
Human Papilloma Virus (also available in Spanish)
National organizations and Web sites*
In addition to the American Cancer Society, other sources of
patient information and support include:
Gynecologic Cancer Foundation
Toll free number: 1-800-444-4441 or 1-312-578-1439
Web site:www.thegcf.org/
Centers for Disease Control and Prevention (CDC)
National Breast and Cervical Cancer Early Detection Program
Toll free number: 1-800-CDC-INFO (1-800-232-4636)
Web site: www.cdc.gov/cancer/nbccedp
National Cervical Cancer Coalition
Toll free number: 1-800- 685-5531or 1-818-909-3849
Web site: www.nccc-online.org
*Inclusion on
this list does not imply endorsement by the
American Cancer Society.
No matter who you are, we can help. Contact us anytime, day or
night, for information and support. Call us at 1-800-ACS-2345 or
visit
www.cancer.org.
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