Cervical Cancer Fundamentals
The cervix is the lower portion of the uterus that forms a canal that opens into the vagina.
Cervical cancer starts in the lining of the cervix and occurs when normal cells in the
cervix become abnormal. Cervical cancers do not form suddenly, but gradually develop from
pre-cancerous changes. Not every precancerous change will develop into cervical cancer.
World Perspective
Worldwide, cervical cancer is the second most common cancer in women (after breast cancer)
and is the third leading killer (behind breast and lung cancer). Approximately 500,000 cases
of cervical cancer are diagnosed each year worldwide. In the United States, however, cervical
cancer is only the 8th most common cancer of women. This difference is due to the success of
screening with the Pap test.
Who gets Cervical Cancer?
Infection with human papillomavirus (HPV), which is transmitted sexually, is strongly
associated with cervical cancer and is the major risk factor. HPV is found in nearly 80%
of cervical carcinomas. Human immunodeficiency virus (HIV) infection reduces the immune
system's ability to fight infection, including HPV, which increases the likelihood that
precancerous cells will progress to cancer. Genital warts are caused by different HPV
types, and are not related to cervical cancer.
Sexual activity can increase the chance for infection with HPV, HIV and for cervical
cancer. The following are risk factors:
- Having multiple sexual partners or having sex with a promiscuous partner
- History of sexually transmitted disease (STD)
- Sexual intercourse at a young age
Understanding the Language
Doctors use several terms to describe pre-cancerous changes in the cervix, including
cervical intraepithelial neoplasia (CIN), squamous intraepithelial lesion (SIL), and
dysplasia. The precancerous changes are classified according to the degree of cell abnormality.
Low-grade indicates a minimal change in the cells and high-grade indicates a greater degree of
abnormality and higher risk of going on to cancer in the future.
Screening for Cervical Cancer
Cervical cancer often occurs without any symptoms, so it is important for women to be
sure to have a Pap test as recommended by their physician. The Pap test, (sometimes called a
Pap smear), is done during a pelvic exam and looks for precancerous changes in the cells of
the cervix. These screenings can help detect abnormal cells before they become cancerous.
Finding and treating abnormal cells prevents most cervical cancers from developing. Today,
the majority of women who develop cervical cancer are those who have never had a Pap test,
or who have not had one in a very long time. Cervical cancer has been on the decline for many
years due to this screening process.
Follow–Up Care after an Abnormal Pap Test
If you have an abnormal pap, do not assume you have cancer. Sometimes after an abnormal
Pap test, an exam called a colposcopy is advised. This exam uses a device like a microscope,
called a “colposcope” to look at the cervix and is usually done in your doctor's office. A
small tissue sample or biopsy is taken from the most abnormal areas and sent to the lab for
further evaluation. Colposcopy and biopsy will help your doctor decide if treatment is needed.
Treatment
In some cases, your doctor may recommend treatment to destroy or remove the precancerous
cells from your cervix. These treatments are highly effective in preventing cervical cancer,
and which one is chosen depends upon the abnormality you may have and the equipment available
or preferable to your doctor. Usually, one of three modalities is used:
- cryosurgery (freezing) the abnormal cells
- electrocautery to remove the abnormal cells
- laser to destroy or remove the abnormal cells.
Human Papillomavirus
HPV is a group of about 100 related viruses, and recent studies have shown a handful of
these subtypes of HPV to cause cancer of the cervix. HPV is an extremely common infection,
with half of all sexually active women between 18 and 22 in the U.S. infected. Genital HPV
can be passed from person to person through sexual contact. Unfortunately, condoms do not
appear to greatly decrease the spread of HPV since the virus can also live on the scrotum
and other areas not covered by a condom. More than 90 percent of HPV infections will disappear
in healthy women who do not smoke and have intact immune systems, so most women with HPV do
not develop precancer or cancer of the cervix. But sometimes infection persists and can cause
cervical cancer decades later.
HPV Vaccine–at Last!
The Centers for Disease Control and Prevention (CDC) recommends routine vaccination with the new HPV vaccine "for females aged 11-12 years; the vaccination series can be started in females as young as age 9 years; and a catch-up vaccination is recommended for females aged 13-26 years who have not been vaccinated previously or who have not completed the full vaccine series." Ideally, the vaccine should be given before having sex for the first time, since nearly any sexual encounter carries the risk of transmitting HPV. The vaccine has been shown to be nearly 100% effective in protecting against the four strains of HPV considered most prevalent. At the moment, there is only one vaccine on the market, but others are in development. Immunization provides protection against four HPV strains. The current treatment regime is three injections over a six-month period.
Symptoms of Cervical Cancer
Although cervical cancer often has no symptoms, the following may occur:
- Bleeding – light spotting after sexual intercourse, bleeding between
menstrual periods, increased menstrual bleeding
- Abnormal (yellow, odorous) vaginal discharge
- Painful sexual intercourse
Cervical cancer that has spread (metastasized) to other organs may cause constipation,
back pain, blood in the urine, a lump on the cervix, and blockage in the tube (ureter)
that carries urine from the kidney to the bladder.
