Screening for cervical cancer has greatly reduced the rates of cervical cancer. Cervical cancer screening usually consists of a Pap test (also called a Pap smear or cervical cytology) and, in some women, a test for human papillomavirus (HPV), a virus that can cause cervical cancer. Women who are found to have abnormal cells that are precursors to cancer (called a precancerous lesion) of the cervix need further follow-up or treatment. Cervical abnormalities may be referred to as cervical dysplasia, cervical intraepithelial neoplasia (CIN), or adenocarcinoma in situ (AIS).
The outer surface of the cervix has cells called squamous cells. A precancerous lesion affecting these cells is called CIN. These changes are categorized as being mild (CIN 1) or moderate to severe (CIN 2 or 3).
The canal of the cervix is lined with glandular cells. A precancerous lesion affecting these cells is called AIS. Precancerous lesions are diagnosed using a cervical biopsy or endocervical curettage (ECC), usually during a colposcopy procedure, which is described elsewhere. (See "Patient information: Colposcopy (Beyond the Basics)".)
Treatments for lesions include cryosurgery (freezing), laser (high-energy light), and excision (surgical removal of the abnormal area, also referred to as a cone biopsy or conization). (See "Patient information: Colposcopy (Beyond the Basics)".)
The tests performed to evaluate abnormal Pap tests are discussed separately. (See "Patient information: Cervical cancer screening (Beyond the Basics)" and "Patient information: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)" and "Patient information: Follow-up of high-grade abnormal Pap tests (Beyond the Basics)".)
Treatment of cervical cancer is discussed in another topic. (See "Patient information: Cervical cancer treatment; early stage cancer (Beyond the Basics)".)
MANAGEMENT OF LOW-GRADE CIN
Low-grade squamous lesions (cervical intraepithelial neoplasia [CIN] 1) usually resolve, but must be followed to make sure that they do not progress to high-grade lesions or cancer. CIN 1 is managed based upon the Pap test and human papillomavirus (HPV)test findings that preceded them:
- CIN 1 biopsy in women with an ASC-US or LSIL Pap test or HPV testing that is persistently positive or shows HPV strains 16 or 18 – ASC-US stands for "atypical squamous cells of undetermined significance." LSIL stands for "low-grade squamous intraepithelial lesion." Follow-up is recommended in one year. (See "Patient information: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)".)
For women ages 25 and older, follow-up should be with a Pap test and HPV test in one year. If CIN 1 persists for two years, either continued follow-up or treatment is acceptable.
For women ages 21 to 24, follow-up should be with only a Pap test in one year. HPV testing is not usually part of cervical cancer screening for young women, because HPV infection usually resolves in these women and their risk of high-grade lesions or cervical cancer is low.
- CIN 1 biopsy in women with an ASC-H or HSIL Pap test – ASC-H stands for "atypical squamous cells, cannot rule out high grade squamous intraepithelial lesion" and HSIL stands for "high-grade squamous intraepithelial lesion." (See "Patient information: Follow-up of high-grade abnormal Pap tests (Beyond the Basics)".)
For women ages 25 and older, follow-up can be one of three options: (1) Pap test and HPV test at one year and then two years; (2) re-review of both Pap test and biopsy results by a pathologist; or (3) immediate treatment with a procedure to remove a larger piece of tissue from the cervix (cone biopsy or loop electrosurgical excision procedure [called LEEP, loop, or LLETZ]).
For women ages 21 to 24, Pap test and colposcopy should be performed every six months.
MANAGEMENT OF HIGH-GRADE CIN
High-grade squamous lesions (cervical intraepithelial neoplasia [CIN] 2 or 3) have a high risk of persisting or developing into cervical cancer over a period of years. In most women, CIN 2 or 3 is treated by removing or destroying the abnormal area. (See 'Choosing the best treatment for abnormal Pap smears' below.)
However, in some women, it is reasonable to delay treatment and instead monitor the abnormal cells. Women younger than 25, for example, can sometimes delay treatment, because high-grade lesions sometimes resolve in women in this age group. Also, pregnant women should delay treatment until after giving birth unless cancerous cell are already present. Women who have not yet had children should be aware that some types of treatment may result in an increased risk of preterm delivery or other complications during a future pregnancy.
MANAGEMENT OF ADENOCARCINOMA IN SITU
Women with a finding on a Pap test of atypical glandular cells (AGC) may be found to have cervical adenocarcinoma or a precancer called adenocarcinoma in situ (AIS). Glandular cancers of the cervix are less common than squamous cancers (cervical intraepithelial neoplasia [CIN] is the precancerous form of squamous cancer).
In some cases, the lab report of a Pap test shows a specific type of AGC. If the type of cells is reported as most likely precancerous (favor neoplasia) or appears to be AIS or adenocarcinoma and the results of a colposcopy procedure are negative, a larger biopsy called a cone biopsy (or a cervical excision) should be performed. This is because the biopsies taken during colposcopy are from the surface of the cervix or the opening of the cervical canal, but glandular abnormalities may be found higher up in the canal. Cone biopsy procedures are described below. (See 'Excision' below.)
If adenocarcinoma is found, this may be treated with an excisional procedure or hysterectomy. Hysterectomy is the preferred treatment in women with AIS who have completed childbearing. For women who elect conservative management with an excisional procedure, repeat excision should be considered if the margins of the initial excision are positive.
CHOOSING THE BEST TREATMENT FOR ABNORMAL PAP SMEARS
Abnormal Pap tests are treated by identifying the area of abnormal cervical tissue and removing it to prevent worsening or spread to other areas of the cervix. There are two main types of treatment for cervical abnormalities:
- Those that destroy the abnormal area (called ablative therapy)
- Those that remove the abnormal areas (called excisional therapy, cervical conization, or a cone biopsy)
Some abnormalities are best treated with one type of treatment while others can be treated with either type, depending upon the patient and clinician's preference. There are some types of abnormalities that can be followed without treatment, if the clinician and patient are willing.
Excisional therapy — Excisional therapies include loop electrosurgical excision procedure (LEEP), also called large loop excision of the transformation zone (LLETZ), laser conization, and cervical conization (sometimes called cold knife conization) procedures. (see 'Excision' below).
Excisional therapy is recommended when the extent or type of cervical abnormality is not clear based upon colposcopy and biopsy or when there is a severe abnormality. In this situation, excision is preferred because the abnormal tissue can be examined with a microscope. This allows the clinician to determine whether the entire abnormal area was removed and whether a more serious condition (cervical cancer) is present.
Ablative therapy — Ablative therapies include cryosurgery and laser ablation. These procedures kill the abnormal cells by freezing or heating them. Ablative therapy may be recommended when there is less concern about cancer or about the extent of the abnormal tissue.
Excision is a procedure that cuts out the abnormal area on the surface of the cervix; excision can also remove abnormalities that extend inside the cervical opening. Excision serves two purposes:
- It provides a sample of tissue to confirm the degree of an abnormality and check for cancerous or precancerous cells deep within the cervix.
- Excision helps to ensure that the abnormality is removed completely. If the edges of the tissue that is removed show evidence of the abnormality or precancer, further treatment may be needed.
Excision can be done in the clinician’s office or operating room after the cervix is injected with local anesthesia to prevent pain. The woman may feel a dull ache or cramp during the procedure. A brown paste is applied after the treatment to prevent bleeding; this often causes a dark vaginal discharge (similar to coffee grounds). Most women are able to return to work or school after the procedure.
Following a cervical excision, most women have mild to moderate vaginal bleeding and discharge for one to two weeks. The bleeding should not be heavy (eg, should not soak a pad in less than one hour). Care after excision is described below (see 'Post-procedure care' below).
Loop electrosurgical excision procedure (LEEP) — Excision can be done in the clinician’s office or in the operating room with a device that uses electrical current; this is called a loop electrosurgical excision procedure (LEEP) or large loop excision of the transformation zone (LLETZ). A thin, wire loop is inserted through the vagina, where it uses an electric current to remove a cone-shaped portion of the cervix. This can also be performed with a laser knife, which uses high intensity energy from a light beam.
Cervical cone biopsy (conization) — Excision can also be done with a scalpel or laser instead of a loop; this is called a cervical conization or cone biopsy (figure 1). Conization is usually done in an operating room after the patient has received general anesthesia (medicine given to induce sleep) or regional anesthesia (eg, epidural or spinal).
Complications — As with any surgical procedure, complications can occur during excision. These include:
- Bleeding during the procedure — Bleeding is rarely serious, and can usually be managed with suturing or by applying cauterizing material (a liquid or treatment that helps the blood to clot) to the cervix.
- Bleeding after the procedure — Although light bleeding or spotting is normal, some women have heavy bleeding several days or weeks after the procedure. This can usually be treated in the office, but occasionally a procedure in an operating room is necessary.
- Infection — Infections occur rarely after cone biopsy, either on the cervix itself or elsewhere in the reproductive tract. Most infections can be treated with oral antibiotic therapy.
- Perforation of the uterus — This is an uncommon complication, and is more likely to occur in women who are postmenopausal or whose uterus is tipped forward. If the uterus is perforated, it usually heals without any need for treatment. Infrequently, additional surgery is needed to see and repair injuries to internal organs.
- Late complications — (see 'Pregnancy after treatment for abnormal Pap smear' below).
Ablative treatments destroy, rather then cut away, abnormal cervical tissue.
Cryosurgery — Cryosurgery involves applying liquid nitrogen or carbon dioxide to the cervix. This causes the cervical tissue to freeze, which destroys the abnormal cells. Cryosurgery can be done in the office, similar to a pelvic examination, without any anesthesia. It may cause mild cramping or discomfort.
Cryosurgery is not recommended in certain situations, such as when the extent and type of cervical abnormality are not clear based upon colposcopy and/or biopsy. Excisional therapy is preferred in these cases.
Most women have watery vaginal discharge for one week after cryosurgery. Care after cryosurgery is described below (see 'Post-procedure care' below).
Laser ablation — Laser ablation uses high intensity energy from a light beam to destroy abnormal areas of the cervix. The laser is directed to the abnormal area of the cervix through the vagina. This is usually performed in an operating room after the woman has received general anesthesia or regional anesthesia (eg, epidural or spinal). Laser treatment requires special training and equipment.
Like cryosurgery, laser ablation destroys the abnormal tissue, which means that the tissue cannot be examined under a microscope and analyzed. As a result, laser ablation is not recommended in certain situations, such as when the extent and type of cervical abnormality are not clear based upon colposcopy and/or biopsy.
Most women have vaginal discharge for one to two weeks after laser treatment. Care after laser treatment is described below (see 'Post-procedure care' below).
All women should ask about their ability to drive home from the procedure and when they can resume normal daily activities. Following treatment, most providers recommend avoiding sexual intercourse, not placing anything in the vagina (eg, douches, tampons), and not taking a bath or swim for a few weeks (showers are fine); other clinicians may recommend a shorter period of "pelvic rest". This should be discussed in detail with the clinician.
In general, a woman should call her provider if she has bleeding that is heavier than a normal menstrual period (defined as soaking a pad in less than one hour, especially if there are clots), severe or worsening pain, fever over 101ºF (38.4ºC), or a foul-smelling vaginal discharge.
Treatment efficacy — Although the treatments described above are effective, recurrence or persistence of cervical dysplasia is common and occurs in up to 30 percent of women. Women that are not cured after a first treatment may have persistence, recurrence, or progression of the abnormality, especially if a high risk type of human papillomavirus (HPV, types 16 and 18) is present. Additional treatment is sometimes needed in this case. For this reason, lifelong follow up with cervical cytology smears (Pap test) is important.
Follow up appointments — Typically, a woman is seen for a follow up examination several weeks after treatment to make sure the cervix is healing. The type of follow-up and time interval between subsequent tests will depend upon the results of the initial testing after treatment and the woman's age. Follow up is best discussed with a woman's individual provider since it may vary significantly from one woman to another.
Need for further treatment — Some women will require additional treatments to ensure that all abnormal areas are removed. This is especially true if excision was done and microscopic analysis showed a larger abnormality than was expected. The decision to have additional treatment is individualized, based upon the type of abnormality seen, the woman's risk of cervical cancer, and whether or not childbearing is completed. (See "Patient information: Cervical cancer treatment; early stage cancer (Beyond the Basics)".)
PREGNANCY AFTER TREATMENT FOR ABNORMAL PAP SMEAR
Many women are concerned about the risks of infertility and preterm labor after being treated for an abnormal Pap test. Treatments do not seem to affect fertility. With some types of treatments, there may be some risk of complications during a pregnancy. In general, the data suggest that excisional procedures slightly increase the risk of preterm delivery, but ablative procedures do not. Other factors, such as underlying medical conditions and a woman's age, can also increase a woman's risk of these conditions.
Most women are advised to wait at least three months after a cervical ablation or excision before attempting to become pregnant to allow the tissue to heal fully. (See "Patient information: Preterm labor (Beyond the Basics)", section on 'Cervical length'.)
WHERE TO GET MORE INFORMATION
Your healthcare provider is the best source of information for questions and concerns related to your medical problem.
This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.
Patient level information — UpToDate offers two types of patient education materials.
The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.
Patient information: Cervical cancer (The Basics)
Patient information: Pap tests (The Basics)
Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.
Patient information: Cervical cancer screening (Beyond the Basics)
Patient information: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)
Patient information: Follow-up of high-grade abnormal Pap tests (Beyond the Basics)
Patient information: Cervical cancer treatment; early stage cancer (Beyond the Basics)
Patient information: Preterm labor (Beyond the Basics)
Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.
Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing
Cervical cytology: Evaluation of atypical and malignant glandular cells
Cervical cytology: Evaluation of atypical squamous cells (ASC-US and ASC-H)
Cervical cytology: Evaluation of high-grade squamous intraepithelial lesions (HSIL)
Cervical cytology: Evaluation of low-grade squamous intraepithelial lesions (LSIL)
Cervical intraepithelial neoplasia: Management of low-grade and high-grade lesions
Screening for cervical cancer: Rationale and recommendations
The following organizations also provide reliable health information.
- National Library of Medicine
- National Cancer Institute
- American Society for Colposcopy and Cervical Pathology
(www.cancer.org, search for HPV)
- National HPV and Cervical Cancer Public Education Campaign
- Center for Disease Control and Prevention
The authors and editors would like to recognize Dr. William Mann, who contributed to previous versions of this topic review.