The best way to reduce the risk of vaginal cancer is to avoid known risk factors whenever possible. But since many women with vaginal cancer have no known risk factors, it is not possible to completely prevent this disease.

Infection with human papillomavirus (HPV) may increase a woman's chance of developing vaginal cancer. You can reduce the risk of infection with HPV by delaying onset of sexual intercourse if you are young and by avoiding sex with many persons or with persons who have had multiple partners.

Avoiding HPV infection may reduce a woman's vaginal cancer risk. However, many vaginal cancers do not have evidence of HPV infections, so this approach will not entirely prevent the disease.

A new vaccine has been approved by the FDA that will prevent infection with HPV types 16 and 18. It is recommended for use in young women before they become sexually active. Although there are no studies on whether this will prevent vaginal cancer, there is hope that many cases will be prevented through the use of this vaccine.

Avoiding tobacco use may also reduce your risk of vaginal cancer, in addition to obvious benefits of greatly reducing your risk of developing far more common cancers of the lungs, mouth, throat, bladder, kidneys, and several other organs.

Most vaginal squamous cell cancers are believed to develop from pre-cancerous changes, called vaginal intraepithelial neoplasia (VAIN), that may be present for years before a true cancer forms. Detection of these pre-cancers by regular Pap tests permits treatment to prevent a true cancer from developing.

The American Cancer Society recommends:

• All women should begin cervical cancer screening about 3 years after they begin having vaginal intercourse, but no later than when they are 21 years old. Screening should be done every year with the regular Pap test or every 2 years using the newer liquid-based Pap test.

• Beginning at age 30, women who have had 3 normal Pap test results in a row may get screened every 2 to 3 years with either the conventional (regular) or liquid-based Pap test. Women who have certain risk factors such as diethylstilbestrol (DES) exposure before birth, HIV infection, or a weakened immune system due to organ transplant, chemotherapy, or chronic steroid use should continue to be screened annually.

• Another reasonable option for women over 30 is to get screened every 3 years (but not more frequently) with either the conventional or liquid-based Pap test, plus the HPV DNA test.

• 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 screening. Women with a history of cervical cancer, DES exposure before birth, HIV infection or a weakened immune system should continue to have screening as long as they are in good health.

• Women who have had a total hysterectomy (removal of the uterus and cervix) may also choose to stop having cervical cancer screening, unless the surgery was done as a treatment for cervical cancer or precancer. Women who have had a hysterectomy without removal of the cervix should continue to follow the guidelines above.

How Pap Tests and Pelvic Examinations Are Done

The skin of the outer lips (labia majora) and inner lips (labia minora) will be examined for any visible abnormalities. The health care professional first inserts a speculum, a metal or plastic instrument that keeps the vagina open so that the cervix and vagina can be seen clearly. Next, a sample of cells and mucus is lightly scraped from the ectocervix (part next to the vagina) using a spatula. A small brush or a cotton-tipped swab is used to sample the endocervix (part closest to the body of the uterus).

The sample can be smeared directly onto a glass microscope slide, which is then sent to the laboratory. For about 50 years, all cervical cytology (Pap test) samples were handled this way. This method works quite well and is relatively inexpensive. However, cells smeared onto the slide are sometimes piled up on each other, so cells at the bottom of the pile cannot be clearly seen. Also, infections of the cervix or vagina may cause inflammatory (pus) cells, increased mucus, yeast cells, or bacteria that hide the cervical/vaginal cells. Another problem with direct smears is that the cells may become distorted by drying out. Cells can be difficult to examine accurately if they are not treated with alcohol to preserve them immediately after they are spread on the slide.

A newer method called liquid-based cytology, or liquid-based Pap test, can remove some of the mucus, bacteria, yeast, and pus cells in a sample and can spread the cervical/vaginal cells more evenly on the slide. Instead of being directly placed on a slide, the sample is placed into a special preservative solution. This new method, also known by brand names ThinPrep or AutoCyte, also prevents cells from drying out and becoming distorted. Recent studies show that liquid-based testing can slightly improve detection of cancers, greatly improve detection of pre-cancers (squamous intraepithelial lesions [SILs]), and reduce the number of tests that need to be repeated. This method is more expensive than a usual conventional Pap smear.

The direct smears or liquid-based preparations are usually examined by specially trained technologists (cytotechnologists) and doctors (pathologists). Another approach to improving the Pap test is the use of computerized instruments that can recognize abnormal cells in Pap smears. The AutoPap instrument has been approved by the U.S. Food and Drug Administration (FDA) for retesting Pap test samples that were interpreted as normal by technologists. It is also approved by the FDA for initial screening of Pap smears, instead of screening by a technologist. However, a technologist would still examine all smears identified as abnormal by the AutoPap.

For the pelvic examination, the doctor will feel the organs of the pelvis by inserting a gloved finger of one hand into the vagina while he or she palpates the lower abdomen, just above the pubic bone, with the other. The doctor may include a rectal exam at this time also. For more information on these tests, see "How Is Vaginal Cancer Diagnosed?"

Vaginal Intraepithelial Neoplasia (VAIN; pre-cancer of the vagina) cannot usually be detected during a routine viewing of the vagina. This is why the Pap test is so important. Because cervical cancer is much more common than vaginal cancer, Pap test samples are scraped or brushed from the cervix. However, some cells of the vaginal lining are usually picked up unintentionally (by chance) by the spatula during the procedure. Therefore, many cases of VAIN are found in women whose vaginal lining is not intentionally scraped. Of course, in women whose cervix has been removed by surgery, Pap test samples are purposely taken from the lining of the upper vagina.

As already noted, many women with VAIN may also have a similar condition involving their cervix (cervical intraepithelial neoplasia or CIN). If a Pap test finds CIN, the next step in evaluation (colposcopy) will be to thoroughly examine the cervix, the vagina, and at times the vulva.

How Vaginal Pre-cancers (VAIN) Are Treated

The exact location of VAIN within the vagina is determined by viewing the vaginal lining with a colposcope, an instrument with binocular magnifying lenses. A biopsy confirms the diagnosis. The lesions can be treated by several methods.

Laser surgery focuses a beam of high-energy light to vaporize the abnormal tissue. This is a very effective treatment, particularly with large lesions. However, the colposcopist must be certain that the worst lesion was biopsied and that invasive cancer is not a concern.

Topical chemotherapy: Topical chemotherapy is the use of a chemotherapy drug, fluorouracil (5-FU), applied directly to the lining of the vagina (see "How Is Vaginal Cancer Treated?") in women with VAIN. There are several disadvantages of topical chemotherapy. It must be repeated weekly for about 10 weeks or given nightly for 1 to 2 weeks. It may cause severe vaginal and vulvar irritation, and it may not be as effective as surgical removal or laser vaporization.

Because low-grade VAIN will often disappear without any treatment, some doctors treat only intermediate or high-grade VAIN. They recommend periodic Pap tests (and colposcopy as needed) for low-grade VAIN and reserve treatment for cases that have persisted over time. However, this approach is controversial.

A second drug that can be used topically is called imiquimod. This drug, which comes in a cream, is not chemotherapy. Instead, it causes the body to form an immune response to the tissue where it is applied. In one study, this caused some regression of VAIN, but not permanent cure.

Surgery: A wide local excision or partial vaginectomy (removal of part of the vagina) is rarely performed, but it may be needed to rule out an invasive cancer or if other treatments fail. Last Revised: 07/21/2006