Pap smear

The Papanicolaou (Pap) smear is a screening tool used to detect cervical cancer at an early stage.


Anatomy
The cervix is the neck of the uterus, the female reproductive organ that houses the embryo and fetus during pregnancy. It opens into the vagina.

Purpose
The earlier cervical cancer is found, the more effective treatment will be. In the United States, about 13,000 new cases of cervical cancer are diagnosed each year. Although it's often curable when detected early, the disease still causes about 5,000 deaths in the U.S. each year.
Pap smears can also detect infection, inflammation or other conditions associated with abnormal cells. Pap smears may be done to follow a woman's response to chemotherapy or radiation therapy after treatment for cervical cancer.


Indications
The optimal timing of Pap smears is still being studied. Currently, most experts recommend Pap smears and pelvic exams every one to three years.
The U.S. Preventive Services Task Force (USPSTF) and the American Cancer Society (ACS) recommend that women begin having Pap smears within three years of becoming sexually active or at age 21, whichever is earlier. After that, the USPSTF recommends testing at least every three years. The ACS recommends a Pap test every one to two years, depending on the type of test used, until age 30. Then, if youisk of cervical cancer, you may be able to decrease testing to every two to three years. Discuss the optimal screening schedule with your doctor.

If you're at high risk for cervical cancer, you'll need more frequent testing. Risk factors include:

being infected with certain types of human papilloma virus or HPV (the virus that causes genital warts, a sexually transmitted disease, is a specific HPV)
having multiple sexual partners, which increases your risk of contracting the human papilloma virus
having sexual partners who are at high risk for sexually transmitted diseases
having sex at a young age (In the first few years after menstruation, the cervix undergoes cellular changes that make it more susceptible to cervical cancer if intercourse occurs during this time.)
smoking cigarettes (Carcinogens believed to affect the cervix have been found in the cervical mucus of women who smoke. The risk of cervical cancer increase with the more cigarettes you smoke per day and the longer you smoke.)
having a weak immune system (from infection with HIV, the virus that causes AIDS or taking immunosuppresive medications intended to prevent a transplant rejection, for example)
having a mother who took diethylstilbestrol (DES) when she was pregnant with you (DES is a synthetic estrogen that was given to pregnant women from 1938 to the early 1970s in the United States to treat certain problems during pregnancy. Women whose mothers took DES during pregnancy have an increased risk of a condition known as dysplasia, which may develop into cervical cancer.)
If you've had a hysterectomy (surgical removal of the uterus) due to cervical cancer, you'll continue to need regular Pap smears. If the hysterectomy was done for other reasons, you may not need regular Pap smears. Discuss with your doctor how often you should be tested.


Patient preparation
Pap smears should not be done during your period or when you have a known vaginal infection. Many doctors recommend avoiding douches, tub baths and sex for a day or two before the test. Check with your doctor about using vaginal creams or medications. It's also helpful to empty your bladder before the test.

Procedure
Pap smears are typically done as part of routine pelvic exams in the doctor's office. You'll be positioned on your back on the exam table with your feet in stirrups. The doctor will place a speculum into your vagina to hold it open. Then, a sample of cells is gently scraped from the surface and inside of your cervix with a tiny spatula, brush or swab. The cells will be spread onto a slide and sent to a lab for analysis. A newer technique involves placing the cells into liquid, which are later placed on a slide by a technician at a lab. The entire procedure takes about 10 minutes. Results are usually available in about two to four weeks.

Postprocedure care
You may notice some minor vaginal bleeding after the Pap smear. If this happens, you may want to wear a sanitary napkin. If abnormal changes are detected by the lab, your doctor will determine a schedule for follow-up appointments.

Test explanation
There are a variety of methods available to evaluate Pap smears. You may want to ask your doctor which system is being used to interpret your test. Your doctor will explain the results of your Pap smear and let you know if further testing is necessary. If you don't understand your test results or the doctor's recommendations, ask for clarification.
It's important to keep in mind that the Pap smear is only a screening tool. A formal diagnosis of cancer can only be made after tissue samples are obtained and evaluated in the lab, typically after a biopsy of the cervix.


Benefits
A Pap smear can detect cellular abnormalities of the cervix, as well as screen for cervical cancer. Early detection of cervical cancer is often the key to successful treatment. If the cells from the smear are placed into liquid, this specimen may also be used to test for HPV (the human papillomavirus, a virus that may cause genital warts).

Risks
Occasionally, false negative results are possible, meaning the disease is actually present but the test result is reported as normal. Researchers are studying new computer-assisted technology for Pap smear interpretation to determine if it can decrease the number of false negative results in a cost-effective manner.

Pregnancy-specific information
When you're pregnant, Pap smears are routinely done at the first prenatal visit. If cancerous cells are detected, consider having a team of doctors determine the best treatment plan for you and your baby. You may want to include your obstetrician and a gynecological oncologist (a doctor who specializes in the treatment of female pelvic cancer). Depending on the extent of the disease, cancerous cells on the cervix may pose problems during the pregnancy.

Senior-specific information
If you're at low risk for cervical cancer after age 65, some medical authorities say regular testing is no longer necessary. Half of all cervical cancer fatalities occur in women over age 65, however.
The USPSTF and ACS say that it may be acceptable to stop cervical cancer screening after age 65 to 70 if you've had at least three normal Pap smears within the last 10 years with no abnormal results. The decision to stop screening should only be made after consultation with your doctor, however. Many older women have not had sufficient cervical testing, and individual risk factors may make continued screening important.