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CANCER
FACTS National Cancer Institute National
Institutes of Health (NIH)
Key Points
- A Pap test and pelvic exam are important
parts of a woman’s routine health care
because they can detect cancer or abnormalities
that may lead to cancer of the cervix
(see Question 3).
- Women should have a Pap test at least
once every 3 years, beginning about 3
years after they begin to have sexual
intercourse, but no later than age 21
(see Question 6).
- If the Pap test shows abnormalities,
further tests and/or treatment may be
necessary (see Question 11).
- Human papillomavirus (HPV) infection is the primary risk factor for cervical
cancer (see Question 13).
| 11. |
What if Pap test results are abnormal?
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If the Pap test shows an ambiguous or minor abnormality, the physician may repeat the test to determine whether further followup is needed. Many times, cell changes in the cervix go away without treatment. In some cases, doctors may prescribe estrogen cream for women who have ASC–US and are near or past menopause. Because these cell changes are often caused by low hormone levels, applying an estrogen cream to the cervix for a few weeks can usually help to clarify the cause of the cell changes.
If the Pap test shows a finding of ASC–H, LSIL, or HSIL, the physician may perform a colposcopy using an instrument much like a microscope (called a colposcope) to examine the vagina and the cervix. The colposcope does not enter the body. During a colposcopy, the physician may coat the cervix with a dilute vinegar solution that causes abnormal areas to turn white. The physician may also perform a biopsy (a biopsy is the removal of a small piece of tissue for study in a lab).
The physician may also perform endocervical curettage. This test involves scraping cells from inside the endocervical canal with a small spoon-shaped tool called a curette. The doctor may also remove a small piece of cervical tissue for examination. This procedure is called a biopsy. The cells or tissue are sent to a lab for study under a microscope.
If the lab finds abnormal cells that have a high chance of becoming cancer, further treatment is needed. Without treatment, these cells may turn into invasive cancer. Treatment options include the following:
LEEP (loop electrosurgical excision procedure) is surgery that uses an electrical current which is passed through a thin wire loop to act as a knife.
Cryotherapy destroys abnormal tissue by freezing it.
Laser therapy is the use of a narrow beam of intense light to destroy or remove abnormal cells.
Conization removes a cone-shaped piece of tissue using a knife, a laser, or the LEEP technique.
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| 12. |
How do terms for Pap test abnormalities compare, and which tests and treatment options may be appropriate?
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Pap Test Result Abbreviation Also Known As Tests and Treatments May Include
Atypical squamous cells–undetermined signficance ASC–US HPV testing Repeat Pap test Colposcopy and biopsy Estrogen cream
Atypical squamous cells–cannot exclude HSIL ASC–H Colposcopy and biopsy
Atypical glandular cells AGC Colposcopy and biopsy and/or endocervical curettage
Endocervical adenocarcinoma in situ AIS Colposcopy and biopsy and/or endocervical curettage
Low-grade squamous intraepithelial lesion LSIL Mild dysplasia or Cervical intraepithelial neoplasia–1 (CIN–1) Colposcopy and biopsy
High-grade squamous intraepithelial lesion HSIL Moderate dysplasia, Severe dysplasia, CIN–2, CIN–3, or Carcinoma in situ (CIS) Colposcopy and biopsy and/or endocervical curettage Further treatment with LEEP, cryotherapy, laser therapy, conization, or hysterectomy
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| 13. |
How are human papillomaviruses (HPVs) associated with the development of cervical cancer?
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Human papillomaviruses (HPVs) are a group of more than 100 viruses. Some types of HPV cause the common warts that grow on hands and feet. Some HPVs are sexually transmitted and cause wart-like growths on the genitals, but these types do not lead to cancer. More than a dozen other sexually transmitted HPVs have been linked to cervical cancer.
HPV infection is the primary risk factor for cervical cancer. However, although HPV infection is very common, only a very small percentage of women with untreated HPV infections develop cervical cancer.
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| 14. |
Who is at risk for HPV infection?
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| HPV infection is more common in younger age groups, particularly among women in their late teens and twenties. Because HPVs are spread mainly through sexual contact, risk increases with number of sexual partners. Women who become sexually active at a young age, who have multiple sexual partners, and whose sexual partners have other partners are at increased risk. Women who are infected with the human immunodeficiency virus (HIV) are also at higher risk for being infected with HPVs and for developing cervical abnormalities. Nonsexual transmission of HPVs is rare. The virus often disappears but sometimes remains detectable for years after infection. |
| 16. |
Have any studies been done to examine HPV testing and treatment options for mild Pap test abnormalities?
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Findings of the ASCUS/LSIL Triage Study (ALTS), a major clinical trial (research study with people) funded and organized by the National Cancer Institute (NCI), suggest that HPV testing in women with ASC–US may help identify underlying abnormalities that need a doctor’s attention. The study results suggest that testing cervical samples for HPVs can identify which ASC–US abnormalities need treatment. A negative HPV test can provide reassurance that cancer or a precancerous condition is not present.
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| 17. |
What are false positive and false negative results?
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The Pap test is a screening test and, like any such test, it is not 100-percent accurate. Although false positive and false negative results do not occur very often, they can cause anxiety and can affect a woman’s health.
A false positive Pap test means that a patient is told she has abnormal cells, but the cells are actually normal. A false negative Pap test occurs when a specimen is called normal, but the woman has a significant abnormality that was missed. A false negative Pap test may delay the diagnosis and treatment of a precancerous condition. However, regular screening helps to compensate for the false negative result. If abnormal cells are missed at one time, chances are good that the cells will be detected the next time.
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| 18. |
What methods are being developed to improve the accuracy of Pap tests?
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In April 1996, the Consensus Development Conference on Cervical Cancer, which was convened by the National Institutes of Health (NIH), concluded that about half of false negative Pap tests are due to inadequate specimen collection. The other half are due to a failure to identify or interpret the specimens correctly. Although the conventional Pap test is effective in the majority of cases, the conference made it clear that new methods of collecting and reading specimens are needed to reduce the number of false negatives.
The Bethesda System requires laboratories to determine whether there are enough cervical cells in the specimen to make a proper evaluation. This requirement helps improve the quality of samples and sample collection. The Bethesda System requires a sample to be categorized as “satisfactory for evaluation” or “unsatisfactory for evaluation.”
One new method of collecting and analyzing samples is called liquid-based thin-layer slide preparation. This method may make it easier to screen for abnormal cells. Cervical cells are collected with a brush or other collection instrument. The instrument is rinsed in a vial of liquid preservative. The vial is sent to a laboratory, where an automated thin-layer slide device prepares the slide for viewing. Results of this method suggest that it is comparable to, or more sensitive than, standard Pap tests for the detection of significant abnormalities.
Computer image directed automated readers are also being used to improve the reading of Pap tests. This technology uses a microscope that conveys a cellular image to a computer, which analyzes the image for the presence of abnormal cells
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| 19. |
Is there a vaccine against HPV or cervical cancer?
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Cervical cancer is primarily caused by the HPV virus (99.7%). So a vaccine stopping HPV would appear to stop cervical cancer. Among the vaccines under development, two of the companies are in Phase III clinical trials (Glaxo & Merck) and appear close to providing data to the FDA. These vaccines focus in on HPV types 16 and 18 which account for 70% of the cervical cancers. For the vaccine to be effective, it is believed that the vaccine should be provided to children prior to their sexual activity (Age 10-12).
There are still some questions surrounding the vaccine with regard to how long the vaccine lasts? When will there need to be a booster vaccine? Should boys as well as girls be vaccinated. Studies indicate the vaccines may be close to 100% effective. Currently up to 80% of women are positive for HPV by age 50. Imagine a vaccine that can dramaticlly reduce that positive number and virtually eliminate HPV type 16 and 18. The HPV vaccines appear to be the new frontier in the prevention war against cervical cancer. |
| 20. |
I have been told I have Stage "O" adenocarcinoma cervical cancer. I already had a Cone biopsy. I want to still have children. My doctor wants to follow me up with regular Pap smears, is that OK?
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Stage 0 adenocarcinoma is also known as adenocarcinoma "in situ". If cone biopsies completely remove the tumor, then Pap follow up is acceptable and completely OK in women 30-35 or younger. If childbearing is strongly desired then follow-up with paps is OK if the risk of a recurrence is understood (the risk is directly related to the pathology speicmen and how far the tumor is from the edge of the resection margin. The hysterectomy should be eventually performed (after the disire for childbearing is concluded) as the long term risk of recurrence and progression of the cancer in the remaining cervix is unknown.
The next step is a review of the pathology specimens by an expert and an assessment of risk. Following that, there should be a conference between the pathologist and the gynecologist / gynecologic oncologist and then a plan formulated with the patient. |
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