Pap test

What is being tested?
The Pap test is used to look for abnormal or potentially abnormal cells in the vagina and cervix. It is a screening test for women that can detect precancerous changes as well as cervical cancers that can be treated easily and quickly. Infections of the uterus due to various bacteria, fungi and viruses can also be diagnosed with this test.

How is the sample collected for testing?
The conventional method involves collecting cell samples from the cervical area. The sample is taken with a wooden “spatula”, a swab or a small brush. Newer liquid-based methods, which are modifications of the conventional Pap test, are also available. The sample is taken as described above but is not placed directly on a slide. It is placed in a special liquid preservative. This cell suspension is then processed onto a slide, stained and examined.

Is any preparation needed to ensure a good-quality sample?
You are asked not to shower or bathe in the 24 hours before the Pap test. You may also be asked to avoid sexual activity in the 24-48 hours before the test. Do not use any vaginal creams or foams in the 48 hours before the test, and do not have the test during your period.

1. How is it used?
2. When is it requested?
3. What does the test result mean?
4. Is there anything else I should know?

1. How is it used?
The doctor requests the Pap test to look for vaginal or cervical cells that are cancerous or potentially precancerous. A sample of cervical cells or cell suspension is placed on a slide, stained with a special stain (Pap stain) and examined under the microscope by a cytotechnologist or pathologist. The Pap test can also be used to detect vaginal and/or uterine infections. Abnormal cells and infections may be present without causing symptoms. Some of these infections may need treatment, while others may resolve on their own or need further tests and monitoring over time. Some strains of human papillomavirus, a virus commonly transmitted sexually, may be associated with an increased risk of cervical cancer. An HPV DNA test may be requested on its own or after a Pap test, especially for women over 30.

2. When is it requested?
How often the Pap test should be done depends on age and sexual activity (see cervical cancer screening (13-18 years), (19-29 years), (30-49 years), (over 50 years)).
The American College of Obstetricians and Gynecologists (ACOG) revised its guidelines in 2009 and recommends that Pap test screening should not start before the age of 21 and should then be repeated every 2 years until the age of 29. From the age of 30 onwards, the Pap test should be requested once every three years after 3 consecutive normal Pap tests with no abnormalities. ACOG also recommends that women aged 30 or over be offered an HPV DNA test together with the Pap test. If both are negative, the test should not be repeated for three years.

If a woman has a particular medical history, the Pap test may be repeated more often. Some of these conditions include:

• HIV
• A suppressed immune system, for example in people who have had a transplant
• When the woman’s mother took DES (diethylstilbestrol) during pregnancy.
• women previously treated for cancer or for cervical intraepithelial neoplasia 2 or 3 (CIN 2, CIN 3)

In other situations the Pap test may be requested, for example when a woman has several sexual partners, is pregnant or has abnormal vaginal bleeding, pain, sores, discharge or itching.

3. What does the test result mean?
A “negative” Pap test means that the cells obtained appear normal and there is no identifiable infection. In some cases the conventional Pap test may be “unsatisfactory” for assessment. This may mean that not enough cells were collected or that the cells cannot be clearly identified.

• Unsatisfactory: inadequate sample or presence of interfering substances
• Benign: no cancer cells, but the smear shows infection, irritation or normal cells repairing.
• Atypical cells of undetermined significance: abnormal changes in the cells covering most of the outer part of the cervix (squamous cells, ASCUS) or in the cells lining the opening of the uterine canal, for which the cause has not been determined; an ASCUS result is often followed by a DNA test to check for high-risk HPV infection.
• Low-grade changes: often due to HPV infection, which in some cases can increase the risk of cervical cancer; this result may be followed by a DNA test to check for HPV infection
• High-grade changes: the cells are highly atypical and may be cancerous
• Squamous cell carcinoma or adenocarcinoma: terms used to identify certain types of cancer; in these cases the cancer is evident and requires immediate attention.

According to the National Cancer Institute, about 55 million Pap tests are carried out in the United States every year. Of these, about 3.5 million are abnormal and need follow-up

4. Is there anything else I should know?

The Pap test is generally used as a screening test. A certain percentage of women with abnormal cells may not be identified by a single Pap test, which is why it is important to have Pap tests regularly. A significant limitation of the test relates to sample collection.
The Pap test represents a limited number of the cells present on the cervix and in the vaginal area. Even for the most experienced doctor, sample collection may occasionally be inadequate and the sample may need to be taken again.
When done routinely, the Pap test has been of great help in diagnosing and treating precancerous areas and helps prevent cervical cancer from developing. The test also helps detect cervical cancer at an early stage, when it is most curable.
The Pap test is also used to check abnormalities that in many cases are part of the body’s repair process and often resolve without further treatment.
Showering, bathing or using vaginal creams in the 48 to 72 hours before the test may make the test “unsatisfactory”. Other factors that could affect the results include menstrual bleeding, infections, the use of medicines (such as digitalis and tetracycline) and sexual activity in the 24 hours before the test.
In these cases the Pap test may need to be repeated, but this does not necessarily mean there is a significant problem. In some cases the use of liquid-based techniques can remove interfering material such as blood and/or mucus that could obscure a clear, orderly view of the cervical cells. A second advantage is that the same sample can be used for the additional HPV test, if needed.

1. What are the risk factors for cervical cancer?
2. Does an abnormal Pap test always mean cancer?
3. If I have cervical cancer, what are the treatment options?

1. What are the risk factors for cervical cancer?
The most important risk factor for cervical cancer is infection with human papillomavirus (HPV). Tests are available to diagnose this type of infection and are often carried out at the same time as the Pap test. A vaccine to prevent HPV infection is also available. The vaccine is given in three doses over six months and is most effective if given before becoming sexually active.
Increased risk is also associated with the age at which sexual activity begins (the earlier a person becomes sexually active, the higher the risk), multiple sexual partners, smoking, a medical history of exposure to diethylstilbestrol and other sexually transmitted diseases such as herpes or HIV.

2. Does an abnormal Pap test always mean cancer?
A single “abnormal” Pap test does not necessarily mean there is cancer. The membranes covering the cervix undergo constant repair and change. Treatment may not be needed, but the situation should be monitored carefully. This may require repeating the Pap test every 3-6 months until the situation has resolved.

3. If I have cervical cancer, what are the treatment options?
Cervical cancer is a slow, progressive disease and may take years to spread beyond the cervix. Because of this, regular gynaecological check-ups offer the best chance of preventing cancer by allowing precancerous tissue to be diagnosed and removed.
Regular check-ups can detect this type of cancer early. Minimally invasive surgery on the cervix (terms your doctor may use include LEEP, conisation, “cold knife” or cryotherapy), which removes precancerous tissue or very early-stage cancerous tissue, is the standard treatment.
In more advanced cervical cancers, a hysterectomy may be carried out. If the cancer spreads to other tissues (metastasises), radiotherapy may be needed and, in some cases, further surgery.