According to the National Cancer Institute, when the Pap test shows an ambiguous or minor abnormality, the test is usually repeated to ensure accuracy.
If the test shows a significant abnormality, a colposcopy may be performed (using an instrument called a colposcope) to examine the vagina and the cervix.
A Schiller test may also be performed, in which the cervix is coated with an iodine solution. The iodine stains healthy cells brown, while abnormal cells maintain their typical white or yellow color.
A biopsy may be performed in which the physician removes a small amount of cervical tissue for examination by a pathologist. This is the only sure way to determine whether the abnormal cells indicate cancer.
A Pap test (sometimes called a Pap smear) is a way to examine cells collected from the cervix, or the "mouth" of the womb (located at the top of the vagina), for the presence of:
- abnormal cells
A Pap test, along with a pelvic examination, is an important part of a female's routine health care because it may detect abnormalities that can lead to invasive cancer. Most invasive cancers of the cervix can be detected early if females have Pap tests and pelvic examinations regularly. As with many types of cancer, cancer of the cervix is more likely to be successfully treated if it is detected early.
But, the Pap test is not only useful in detecting cancerous cells, it can detect other changes in the cervix and vagina, including dysplasia, or pre-cancer cells. Inflammation in the cervical area may also be detected. Inflammation may be caused by:
- yeast infections
- trichomoniasis infections
- medications or other chemicals
- miscarriage (or abortion)
A woman should always consult with her physician about when and how often a Pap test and pelvic examination should be performed.
According to the National Cancer Institute (NCI), the American Cancer Society (ACS), and the American College of Obstetricians and Gynecologists (ACOG), general guidelines include:
- Cervical cancer screening should begin approximately three years after a woman begins having sexual intercourse, but no later than at 21 years old.
- Experts recommend waiting approximately three years following the initiation of sexual activity because transient human papillomavirus (HPV) infections and cervical cell changes that are not significant are common and it takes years for a significant abnormality or cancer to develop. Cervical cancer is extremely rare in women under the age of 25.
- Women should have a Pap test at least once every three years.
- The American Cancer Society (ACS) and the American College of Obstetricians and Gynecologists (ACOG) recommend annual cervical cytology screening with regular Pap tests or biannual (every two years) screening with liquid-based tests (Thinprep) until age 30. Women under age 30 have a higher likelihood than older women of acquiring high-risk types of HPV that cause premalignant cervical disease, which should be ruled out before extending the testing intervals.
- ACS and ACOG recommend that at or after age 30, women who have had three normal test results in a row may get screened every two to three years. However, women with certain risk factors such as human immunodeficiency virus (HIV) infection, a weak immune system, in utero DES exposure, or a previous diagnosis of cervical cancer may need more frequent screening.
- Women 65 to 70 years of age who have had at least three normal Pap tests, sexually inactive, and no abnormal Pap tests in the last 10 years may decide, upon consultation with their healthcare provider, to stop cervical cancer screening.
- Women who have had a total hysterectomy (removal of the uterus and cervix) do not need to undergo cervical cancer screening, unless the surgery was done as a treatment for cervical precancer or cancer.
- Women should seek expert medical advice about when they should begin screening, how often they should be screened, and when they can discontinue cervical screenings, especially if they are at higher than average risk of cervical cancer due to factors such as HIV infection or infection with the HPV virus.
In the past few years, a newer way of testing cervical cells for abnormalities has gained acceptance in the medical community. This procedure is called liquid-based cytology. Approved by the US Food and Drug Administration (FDA), the test is a liquid-based procedure in which cells from the cervix are put into a vial of liquid instead of being "smeared" onto a slide. The liquid is then filtered and only the cervical cells are placed onto a slide for examination. Though the cost of the procedure, called Thinprep, AutoCyte, or SurePath, is double what a Pap test costs, studies show that these tests may require fewer repeat tests and detect more early-stage lesions. Consult your physician for more information.
When abnormal cells are identified on a Pap test, additional testing is generally recommended in order to determine if the abnormality requires treatment. However, a 2006 report from the American College of Obstetricians and Gynecologists (ACOG) recommends that abnormal Pap test results in adolescents may be managed somewhat differently.
Most cervical lesions of a lower grade will go away without treatment in adolescents. Thus, ACOG's current recommendation is to repeat the Pap test at 6- or 12-month intervals for a year after the original abnormal Pap test, depending on the individual situation of the adolescent involved. However, the plan of action for further testing and treatment after abnormal results from a Pap test will depend on the type of abnormality found and the adolescent's general health status.
Because certain strains of HPV have been found to cause most cases of cervical cancer, research efforts have focused on developing a vaccine against HPV. Two HPV vaccines have been developed, and clinical trials of these vaccines have been successful.
One of the vaccines, Gardasil®, was approved by the US Food and Drug Administration in 2006 and can protect women from HPV infections. It protects against four types of the HPV virus, including the two viruses that cause 90 percent of genital warts. Gardasil can only be used to prevent HPV infection before an abnormal pap test develops.
Gardasil is administered as a series of three injections over a six month period. Recommendations for giving this vaccine are still being discussed but many professionals feel the vaccine should be given to girls before they become sexually active.
Click here to view the
Online Resources of Adolescent Medicine