You probably have a Pap test every one to three years as you should! The test reveals cancer of the cervix, the internal gateway between the vagina and the uterus. More importantly, the Pap detects problematic changes before cells become cancerous, when the condition is most easily treated.
Before the Pap test was developed, cervical cancer was the number one cause of cancer deaths in women...now it ranks 15th. But the fight is not yet won. In the US, 70% of new cervical cancers are diagnosed in women who have not had regular Pap tests or whose abnormal results were not followed up with appropriate additional testing for and treatment of precancerous lesions.
If you are among the three million to four million US women per year whose Pap results are "abnormal," you probably are confused about what this means and what to do next. The answers you need…
Cancer Culprit: HPV
Cervical cancer is almost always caused by infection with human papillomavirus (HPV). Of the more than 100 strains of this sexually transmitted virus, 15 are linked to cervical cancer. Nearly 80% of sexually active women become infected at some point, but usually HPV disappears on its own, so HPV testing is not done on a routine basis.
However: Occasionally, HPV persists and, over many years, can cause cellular changes that lead to cervical cancer.
What happens: Like any virus, HPV can take over a cell and alter its DNA. The purpose of the Pap test is to detect and grade precancerous HPV-infected cells so doctors can provide the appropriate subsequent tests and treatments to prevent the cells from progressing to cancer.
During a Pap test, the doctor uses a small brush or spatula to scrape two types of cells from the cervix-squamous cells from the epithelium (skin) on the surface of the cervix...and mucus-producing glandular cells from the endocervical canal, the narrow channel that runs from the cervix into the uterus.
The cells are transferred to a glass slide...or to a vial of liquid preservative (such as the ThinPrep or SurePath brand). Slides made from the liquid are easier to analyze. If the Pap results are abnormal, the remaining liquid can be tested for HPV.
Test Interpretation
Within a few weeks of your Pap smear, your health-care provider should notify you of the test results. If you are told simply that your results are abnormal, ask for the specific term for your type of abnormality. Then check the list below for an explanation of the term. The follow-up recommendations given are appropriate for most adult women. (Guidelines for adolescents and pregnant women differ--consult your doctor for more on these.)
A Pap test result of…
- Negative-or negative for intraepithelial lesion for malignancy-means results are normal and cervical cells look fine.
About 90% of Paps are negative.
What's next: No action is needed until your next regularly scheduled Pap test. If you are under age 30, have a Pap every one to two years. If you are 30 or older and have had three consecutive negative Paps, your doctor may suggest waiting two to three years between tests because your risk is low and cervical cancer grows slowly.
- ASC-US-or atypical squamous cells of undetermined significance-are slightly abnormal but not obviously precancerous. Caution is warranted-about 13% of ASC-US abnormalities are associated with a more serious or "high-grade lesion called HSIL (described later).
What's next: Your doctor will recommend one of three courses...
- Repeat the Pap test after six months and again after another six months. Most women return to normal by the first repeat test-but two tests are needed for confirmation. If both repeat tests are normal, you don't need to do anything until your next annual Pap.
If your second test result also is ASC-US, your doctor will do a colposcopy (examination of the cervix using a magnifying instrument) and perhaps a biopsy (removal and analysis of a small tissue sample) of any abnormal area.
If your second or third Pap test indicates a "low-grade" lesion called LSIL or if it indicates HSIL, see these categories below.
- Do an HPV test. If it is negative, your risk of developing HSIL is just 1.4%. If the HPV test is positive, your HSIL risk is 27%—so you need a colposcopy.
- Skip additional tests and get a colposcopy. This is best if your most recent previous Pap result also showed ASC-US, LSIL or HSIL.
- ASC-H is a subcategory of atypical squamous cells with specific characteristics that might indicate HSIL.
What's next: Colposcopy and biopsy of any abnormal areas.
- LSIL-or low-grade squamous intraepithelial lesion—may indicate a viral skin infection, but in about 27% of cases, it hides high-grade changes.
What's next: Colposcopy and biopsy. If the biopsy is negative or if it confirms LSIL, your doctor should follow you carefully over the next year-repeating the Pap test twice at six-month intervals or doing an HPV test after 12 months. Low-grade changes usually regress without treatment. Even if the LSIL persists for two years, often the best course is to do additional Pap and/or HPV testing rather than to treat the lesion.
- HSIL-or high-grade squamous intraepithelial lesion-indicates more advanced precancerous changes. Fewer than one-third of these lesions disappear on their own. If not removed, they are likely to become cancerous.
What's next: Colposcopy and biopsy. Depending on the findings, your doctor may recommend one of the following surgical treatments...
- Loop electrosurgical excision procedure (LEEP). With this office procedure, abnormal tissue of the cervical lining is cut out using a loop of very thin, heated wire.
- Cone excision. In the operating room, the doctor typically uses a scalpel or laser to remove a cone-shaped area from the cervical lining and underlying tissue.
- Ablation. This office procedure uses either extreme cold (cryotherapy) or extreme heat (laser) to destroy abnormal cervical tissue.
Once the surgery is over, have a Pap test after six months or an HPV test after 12 months to make sure the HSIL hasn't come back.
- AGC-atypical glandular cells are slightly abnormal glandular cells, usually from the endocervical canal or squamous tissue of the cervix.
What's next: Colposcopy and biopsy, including sampling of the endocervical canal...plus an HPV test. A biopsy of the endometrium (uterine lining) also is needed if you are age 35 or older... have abnormal menstrual bleeding...or had Pap results showing abnormal endometrial cells.
- If your biopsy and HPV test are negative, have a repeat Pap and HPV test in one year.
- If the biopsy is negative but HPV is positive, repeat the Pap test and HPV test after six months. If either test is abnormal, have another colposcopy and biopsy.
- If the biopsy is positive, the abnormal area is treated surgically
- AIS-or endocervical adenocarcinoma in situ-indicates a high risk for cancer in the endocervical canal, where it often cannot be seen with colposcopy
What's next: Biopsy and, if necessary, cone excision.
Lifesaving Tests You Need After Hysterectomy
Often hysterectomy does not include removal of the cervix-and if you have a cervix, you still need to be screened for cervical cancer with a Pap smear and, if your doctor recommends it, a test for human papillomavirus (HPV).
But that's not the end of the story. Your gynecologist is the only one of your physicians who routinely checks for vaginal cancer. Although rare, vaginal cancer often goes undetected until it has progressed, because it causes no symptoms in the initial stages. To get an early diagnosis—which increases survival rates-your doctor must visually check your vagina and do a vaginal smear to screen for abnormal cells.
Your gynecologist also needs to check your outer genitalia for cancer of the vulva, the fourth-most-common gynecologic malignancy. In addition, the doctor should do a bimanual exam-one hand on your belly and two fingers inside your vagina-to check for ovarian cancer and colon cancer.
