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Abnormal Pap Smears

Pap smears are screening tests for cervical cancer. During the test, a swab is inserted into the vagina to collect cell samples. The cells are then sent to a lab for examination.

Pap smears have been instrumental in decreasing the number of cases of cervical cancer in the United States by detecting a precancerous condition called dysplasia. Dysplasia is an alteration in the skin of the cervix, vagina, vulva or anus that has the potential to progress to cancer if left untreated.

Dysplasia usually doesn't cause any symptoms, but it may be associated with abnormal bleeding or spotting.

Pap smears are an excellent way to detect dysplasia of the cervix, which is the most common site for dysplasia in women. The test is the most effective form of cancer prevention available to women. It has recently been adapted as a screening test for the anus, to detect anal dysplasias and cancer.

Once dysplasia has been detected on a pap smear, the genital area should be examined under magnification — a procedure known as colposcopy — to identify exactly where the dysplasia is located, followed by removal of the dysplasia if indicated. Anoscopy is using a scope to inspect the anus and lower rectum.

Sometimes, pap smears can be abnormal when there are no pre-cancerous conditions present. Some common types of abnormal pap smears are:

  • Insufficient — There was not enough material to ensure that no abnormal cells were present.
  • Obscuring — There was an infection or bleeding that limited the pathologist's ability to read the pap smear.
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There are a number of ways to remove the abnormal cells created by dysplasia. They include:

  • Loop excision — This technique uses a fine wire loop with electrical energy flowing through it to remove the abnormal area of the cervix. The removed tissue is sent to the laboratory for examination.
  • Cone biopsy — This is an outpatient surgical procedure in which a cone-shaped section of the cervix is removed using a scalpel. The tissue is then sent to the laboratory for examination.
  • Laser therapy — Laser therapy uses a tiny beam of light to vaporize abnormal cells. The laser is directed through a colposcope so that the area and depth of treatment can be controlled precisely.
  • Cryotherapy — In cryotherapy, a probe is used to cool the cervix to sub-zero temperatures. The cells damaged by freezing are shed over the next month in a heavy watery discharge.

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Reviewed by health care specialists at UCSF Medical Center.

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