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Cervical cancer

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Abnormal Pap test results

After cells or tissues are collected from the cervix during a Pap test or biopsy, a pathologist examines the sample to look for changes or abnormalities such as cancer. If there are no abnormal cells, the result is reported as normal, or negative. An abnormal Pap test means that there have been some changes to the cells lining the cervix.

Infection with the human papillomavirus (HPV) is the most common cause of changes to cervical cells. Sometimes cells infected with HPV can become precancerous. Changes to the cervix may also be caused by:

  • viral, bacterial or yeast infection
  • inflammation
  • non-cancerous growths such as polyps or cysts

In some cases, an abnormal Pap test result means that a precancerous condition or cancer is present. Learn more about precancerous conditions of the cervix.

Reporting Pap test results

The Bethesda system is most commonly used to report Pap test results. It uses a standard set of terms to report changes to different types of cells.

Pap test results may show changes to squamous cells or glandular cells. It may also identify other types of cancer, such as sarcoma or melanoma.

Abnormal squamous cell Pap test results

Squamous intraepithelial lesion (SIL) is used to describe changes to squamous cells. SIL is described as low grade (least severe) or high grade (most severe).

Bethesda system resultDescription

atypical squamous cells (ASC)

Cells don’t look normal.

atypical squamous cells – undetermined significance (ASC-US)

Some cells don’t look completely normal.

It’s not clear what the cell changes mean.

low-grade squamous intraepithelial lesion (LSIL)

Cells don’t look normal, but they usually aren’t precancerous.

LSIL is considered a mild abnormality.

atypical squamous cells – cannot rule out high-grade squamous intraepithelial lesion (ASC-H)

Cells don’t look normal.

It’s not clear what the cell changes mean, and a high-grade lesion can’t be ruled out.

The abnormal change may be precancerous.

high-grade squamous intraepithelial lesion (HSIL)

There are abnormal, or precancerous, cells present. The size and shape of the cells have changed. The cells may develop into cancer if they aren’t treated.

squamous cell carcinoma (SCC)

There are cancerous cells present.

Abnormal glandular cell Pap test results

Changes to glandular cells are also included in the Bethesda system.

Bethesda system resultDescription

atypical glandular cells (AGC)

  • AGC – not otherwise specified (NOS)
  • AGC – favour neoplasia (N)
  • adenocarcinoma in situ (AIS)

Cells don’t look normal.

Abnormal cells may be from the cervix or uterus.

adenocarcinoma

There are cancerous cells present.

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Follow-up options for abnormal results

If a Pap test is normal, or negative, you should continue to have regular Pap tests according to your province’s or territory’s screening guideline.

Follow-up for an abnormal Pap test can vary. Depending on how severe they are, some changes or abnormalities may not need to be treated. Some abnormal cells change back to normal on their own. Other abnormal cells or precancerous changes to cells may develop into cancer if they aren’t treated.

Follow-up and treatment options for abnormal Pap test results, based on the Bethesda system are described below.

Atypical squamous cells – undetermined significance (ASC-US)

Follow-up and treatment options for ASC-US include:

  • Pap test
  • HPV test
  • colposcopy (a procedure that uses a lighted magnifying instrument, called a colposcope, to examine the vulva, vagina and cervix)
  • biopsy

A Pap test may be done again at 6 and 12 months to see if the abnormal cells change back to normal on their own. HPV tests are usually only given to women 30 years of age and older. If Pap tests continue to show abnormal changes or the HPV test shows that a high-risk type of HPV is present, then a colposcopy is done. If an abnormal area is found during the colposcopy, then a biopsy may also be done.

Low-grade squamous intraepithelial lesion (LSIL)

Follow-up and treatment options for LSIL include:

  • Pap test
  • HPV test – only given to women 50 years of age and older
  • colposcopy
  • endocervical curettage
  • biopsy (may be done if colposcopy or endocervical curettage is abnormal)

A Pap test may be repeated at 6 and 12 months to see if the abnormal cells change back to normal on their own. If Pap tests continue to show abnormal changes or an HPV test shows that a high-risk type of HPV is present, then a colposcopy, an endocervical curettage and a biopsy may be done.

ASC – cannot rule out high-grade squamous intraepithelial lesion (ASC-H)

Follow-up and treatment options for ASC-H include:

  • colposcopy
  • endocervical curettage
  • biopsy (may be done if colposcopy or endocervical curettage is abnormal)

A colposcopy is done following an ASC-H result. An endocervical curettage and a biopsy may be done during the colposcopy.

High-grade squamous intraepithelial lesion (HSIL)

Follow-up and treatment options for HSIL include:

  • colposcopy
  • biopsy
  • endocervical curettage
  • loop electrosurgical excision procedure (LEEP) or other type of cone biopsy

A colposcopy is done following an HSIL result. An endocervical curettage and a biopsy may be done during the colposcopy.

LEEP or another type of cone biopsy may be done depending on the results of the colposcopy, endocervical curettage or biopsy. This procedure is used to remove abnormal cells and tissue from the cervix.

If the colposcopy is normal (this rarely occurs with an HSIL Pap test result), a woman will have a repeat colposcopy to look for abnormal changes.

Squamous cell carcinoma

Follow-up and treatment options for squamous cell carcinoma (SCC) include:

  • colposcopy
  • biopsy
  • endocervical curettage
  • loop electrosurgical excision procedure (LEEP) or other type of cone biopsy

A colposcopy, an endocervical curettage and a biopsy are usually done following an SCC result.

LEEP or another type of cone biopsy may be done to look for cancer if there is no abnormality found with the colposcopy, endocervical curettage or biopsy. This procedure is used to remove abnormal cells and tissue from the cervix.

Atypical glandular cytology (AGC) and adenocarcinoma

Possible follow-up and treatment of AGC and adenocarcinoma include:

  • colposcopy
  • endocervical curettage
  • endometrial biopsy
  • loop electrosurgical excision procedure (LEEP) or other type of cone biopsy
  • HPV test

A colposcopy and an endocervical curettage are usually done following an AGC or adenocarcinoma result. LEEP or another type of cone biopsy is used to remove abnormal cells and tissue from the cervix. A woman with AGC or adenocarcinoma may also have an HPV test to see if a high-risk type of HPV is present.

Women with AGC-N often have LEEP or another type of cone biopsy to look for cancer if there is no abnormality found with the colposcopy, endocervical curettage or endometrial biopsy.

Pregnant women with abnormal Pap test results

Women who are pregnant and have an abnormal Pap test result may still have colposcopy. If the doctor needs to take a biopsy, this is usually delayed until after the woman has given birth because there is a small chance that taking a biopsy sample can cause bleeding.

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Follow-up procedures

Women with abnormal Pap test results may have one or more of the following procedures.

Human papillomavirus (HPV) test is used to test the cervical cells to see if they have the DNA of certain types of HPV. These high-risk types of HPV are more likely to cause cells to become cancerous. Find out more about HPV test.

Colposcopy uses a colposcope (a lighted magnifying instrument) to examine the vulva, vagina and cervix. During a colposcopy, the doctor may also remove cells or tissue so they can be examined under a microscope (called a biopsy).

Biopsy removes tissues or cells from the body so they can be examined under a microscope to check for cancer. A biopsy can be done during a colposcopy. Find out more about biopsy.

Endocervical curettage is a type of biopsy. It’s a procedure that uses a special tool, called a curette or brush, to remove cells from the endocervical canal. It can be used to collect cells so they can be examined under a microscope to check for cancer. An endocervical curettage can be done at the same time as a colposcopy.

Endometrial biopsy is a procedure that uses a special tool, called a pipelle, to remove cells from the lining of the inside of the uterus (called the endometrium) so they can be examined under a microscope to check for cancer. It can be done during a colposcopy.

Cone biopsy removes a cone-shaped piece of tissue from the cervix. It can be done using a surgical scalpel, LEEP or a laser. The doctor sends the removed tissue to a lab to be examined under a microscope. Find out more about cone biopsy.

Loop electrosurgical excision procedure (LEEP) is a type of cone biopsy. It uses a thin wire heated by an electrical current to remove tissue from the cervix. Find out more about LEEP.

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