PAP SMEAR

PAP SMEAR Simple, life-saving test Adapted from an article originally published by Women's HealthSource, March 1999.

The Pap test ranks among the top success stories of modern medicine, along with antibiotics, insulin and flu vaccine. It's not perfect, but since women began getting Pap tests, deaths from cervical cancer have dropped by about 70 percent. Forty years ago 20,000 women died each year from cancer of the cervix. Today that number is closer to 5,000, a figure that could drop further if more women had the test on a regular basis. Indeed, of those who die of cervical cancer each year, 50 percent haven't had a Pap test done in 5 or more years.

Although getting one is slightly uncomfortable, a Pap test is the best early warning system there is for cervical cancer, even though abnormal results don't always mean cancer. Here's what a woman needs to know about the Pap test, what happens if it's abnormal, and why it should be part of her regular health checkup for life.

Cervical cancer—Preventable and treatable

The test

Six decades ago, George Papanicolaou, M.D., discovered he could detect cervical cancer by studying

Women reproductive system

cells taken from a woman's cervix. It took more than a decade, but his findings were eventually put to use with the test that's named for him, the Pap test (or Pap smear).

Pap Smear

Getting a Pap test is easy. A doctor simply brushes cells from the cervix, smears them onto a glass slide and sends the slide to a lab. A specially trained technician, called a cytotechnologist, examines the slide for abnormal cells. All abnormal cells are further reviewed by a doctor (pathologist) who makes the final diagnosis.

The Pap test isn't foolproof. False-negative results can occur 5 percent to 10 percent of the time. This means that in 1 out of every 10-20 cases of cervical cancer, no abnormality is identified on the Pap smear.

It also means that 90 percent to 95 percent of the time, significant abnormalities are accurately detected. The most common cause of a false-negative Pap smear is "sample failure," which means that no abnormal cells are present on the slide. Sampling errors, either by the woman or her physician, may be due to:

Not preparing optimally — Women should avoid intercourse, douching or using any vaginal medicines or spermicidal foams, creams or jellies for 2 days prior to having a Pap test, as these may wash away or obscure abnormal cells. The best time to have a Pap test is between 10 and 20 days after the first day of a woman's menstrual cycle, or anytime if she is postmenopausal.
Not collecting cells optimally — The doctor needs to collect enough cells from the entire cervical area, smear them onto the slide and "fix" them with preservative immediately

Mistakes can also occur if the cytotechnologist or pathologist fails to identify or correctly interpret abnormal cells. This is more often a problem with small numbers of abnormal cells.

Although abnormal cells can be missed, time is on a woman's side. Cervical cancer takes several years to develop. If abnormal cells are missed at one test, they're likely to be detected with the next test while the cancer is still in its early, most treatable stage.

How often should you be tested?

A woman should work with her doctor to figure out the best schedule. Current guidelines suggest:

Initial Pap test when a woman first begins having sexual relations or at age 18 if not sexually active.
After three consecutive annual normal Pap tests, you may consider less frequent testing.
Subsequent Pap tests at least every 3 years. Continue for life, since the risk of invasive cervical cancer increases with age.
After a hysterectomy (surgical removal of the uterus and cervix), a woman should discuss with her doctor if she needs to continue getting Pap tests. If the hysterectomy was done for a noncancerous condition, such as fibroids, she may discontinue routine Pap tests, but not pelvic exams. If the hysterectomy was done for a precancerous or cancerous condition, the vaginal canal still needs to be checked for abnormal changes.

Who needs more frequent Pap tests? If a woman is at high risk for cervical cancer, she'll need to have more frequent Pap tests. You're at high risk if you:

Became sexually active as a teenager, especially if you had multiple sexual partners.
Have more than one sexual partner now.
Have a history of sexually transmitted disease.
Have a history of abnormal Pap tests.
Have had a diagnosis of cervical cancer or a precancerous Pap test.
Are infected with human papilloma virus, the germ that causes genital warts.
Use tobacco.

Suspicious results Even if your Pap test shows some abnormalities, it doesn't necessarily mean you have cervical cancer. Here are several abnormalities a doctor may find and what the next course of action might be.

Inflammation — This can be caused by a genital tract infection, such as yeast or chlamydia. Your doctor will treat any infection and then repeat the Pap test a few months later.
Low-grade squamous intraepithelial lesions (LSIL) and atypical squamous cells of uncertain significance (ASCUS) — Both of these indicate mild abnormalities, which most often spontaneously revert to normal without treatment. Your doctor may decide that an immediate colposcopy (examination of the tissues through a special magnifying telescope) and biopsy (tissue sample) are warranted since, in a small number of cases, LSIL and ASCUS may progress to high-grade squamous intraepithelial lesions (HSIL) or to cancer. On the other hand, your doctor may advise watchful waiting and repeat Pap tests, especially if you're not at high risk for cervical cancer. A study by the National Cancer Institute is currently under way to help clarify how LSIL and ASCUS should be treated. Results are expected in several years.
High-grade squamous intraepithelial lesions (HSIL). Significant precancerous cells that require further evaluation — Your doctor will most likely perform a colposcopy and a biopsy of suspicious tissues. Treatment is necessary if tissue shows a high-grade lesion.
Carcinoma in situ (CIS) — A cancer that involves only cells on the surface and hasn't spread into deeper tissues. Treatment to remove the cancer is necessary and highly successful.

New techniques If you're a woman and concerned about the accuracy of your Pap test, ask your doctor about several new methods now being used that are intended to reduce the likelihood of false-negative results. Be aware that they may double the cost of a Pap test and may not be covered by insurance. Their added value to the usual Pap smears in detecting abnormalities is controversial.

Computerized screening methods such as PAPNET and AutoPap. These systems are used to rescreen slides after a cytotechnologist has examined them. Although they employ different technologies, both use automated microscopes to scan the slides and computer programs to detect abnormal cells on the manual screening. A cytotechnologist and a pathologist then determine the significance of any abnormal cells found.
ThinPrep — This is a new method to collect and prepare the cells to be screened that makes it easier to read and spot abnormalities. Rather than smearing cells directly onto a slide, the swab used to collect the cells is rinsed in a vial of preservative solution, so no cells are discarded. A machine filters the specimen, reducing blood and mucus, which can obscure the cells to be screened. The machine then applies a thin, even layer of cells to a microscope slide for examination.

Although the Food and Drug Administration has approved these devices, doctors debate their value. Many believe there's only a slight improvement in accuracy. Why take a chance? If a woman gets regular Pap tests, her chances of developing invasive cervical cancer are minimal. But even if she develops cervical cancer, the chances of a cure are as high as 90 percent — if discovered early.