What an LGSIL Pap Smear Result Means

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LGSIL, meaning "low-grade squamous intraepithelial lesion," is one possible result you may get after a cervical cancer screening called the Pap test or Pap smear. The LGSIL, also called LSIL, means mild cervical dysplasia is present. The cells of the cervix are showing slightly abnormal changes.

Mild cervical dysplasia is not cancer or may not even be precancerous, but sometimes may be an indication of abnormalities in cervical cells that could lead to an increased risk of cancer. One study of 1,076 people with LGSIL results found just 8.3% developed a precancerous cervical intraepithelial neoplasia (CIN) condition.

This article explains what LGSIL means on a Pap smear and how it compares to HGSIL and other Pap test results. It presents follow-up tests and treatment that may be done following an LGSIL result.

A doctor holding a pap smear
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LGSIL vs. HGSIL

LGSIL is almost always caused by human papillomavirus (HPV), the primary risk factor for cervical cancer. HPV is easily transmitted through vaginal, anal, or oral sex.

Most people infected with HPV clear the virus spontaneously. For people who are infected with certain types of HPV and whose immune systems cannot clear the virus, cervical cancer may occur.

LGSIL is only one of the possible interpretations of a Pap smear. HSIL, also known as HGSIL (high-grade squamous intraepithelial lesion), is typically more concerning.

It, too, is associated with chronic HPV infection. But where low-grade changes mean mild dysplasia and may not necessarily be a cancer risk, HGSIL has a greater likelihood of turning into cancer and the changes occur faster than if low-grade changes progress.

If not treated, the highly abnormal cells leading to an HGSIL result can progress to cancer, and grow and spread into nearby tissue.

Screening Recommendations

In 2020, the American Cancer Society updated screening guidelines for cervical cancer in people at average risk for the disease. They include:

  • An initial primary HPV test or combination of an HPV test and Pap smear (co-testing) should be done at age 25 (previously, this was age 21).
  • If results are normal, people age 25–65 should have an HPV test or co-testing every five years until age 65. If only cytology (a Pap smear) is available, the patient should repeat the procedure every three years.
  • At age 65, screening may be discontinued for people who have not had an abnormal test classified as CIN2 or above within the last 25 years and have had negative screening tests over the preceding 10 years.

Follow-Up Testing

If you receive a diagnosis of LGSIL, it's important to follow up with your healthcare provider. Their recommendations on how to manage the results will differ according to factors that include:

  • Age
  • History from previous Pap smears
  • Results of an HPV test
  • Additional risks, such as a human immunodeficiency virus (HIV) diagnosis or the use of immunosuppressant drugs

If only a Pap smear was done, the next step may be to perform an HPV test. An HPV test looks for certain strains of HPV associated with cervical cancer.

A lab can usually perform an HPV test on the same cells used on your initial Pap smear, that is, the Pap smear that came back as "abnormal" because of LGSIL.

For those under age 25 with an LGSIL result, HPV testing is not usually done but a pap smear is recommended in one year.

For those over age 25 with LGSIL and a negative HPV test, follow-up testing is based on their specific medical history. It can include:

  • Repeat Pap testing, HPV testing, or both Pap and HPV testing in one year
  • HPV typing to check for types 16 and 18, which can lead to cervical cancer
  • Colposcopy, cervical biopsy, and/or endocervical sampling

colposcopy may be recommended for some people diagnosed with LGSIL, including those who have a positive HPV test (especially if positive for HPV16 or HPV18). It also may be needed when HPV testing wasn't done, or for people who are considered high-risk despite a negative HPV test.

For example, people with LGSIL who are immunosuppressed should proceed to colposcopy even if HPV testing is negative. For people with LGSIL results in pregnancy, a colposcopy may be be delayed until six weeks postpartum.

During the colposcopy, the healthcare provider may also do a cervical biopsy to remove small pieces of cervical tissue. Mild cramping may occur during a cervical biopsy, but it is relatively painless. The tissue samples are then sent to a lab for further examination.

What Happens During Colposcopy?

A colposcopy is an in-office procedure that allows a healthcare provider to perform an in-depth examination of the cervix. When performing a colposcopy, your healthcare provider will use a lighted microscope called a colposcope, which magnifies the cervix so it can be better visualized.

LGSIL Results and High-Risk Conditions

LGSIL results are not typically something to worry about immediately, but people who have an increased risk of developing cervical cancer for other reasons may need earlier or further follow-up.

Conditions considered to add to the higher risk include:

  • People who are living with HIV
  • People who have received a solid organ or stem cell transplant
  • People who are immunosuppressed, such as those taking medication for a rheumatoid disorder like lupus or for inflammatory bowel syndrome
  • People who were exposed to diethylstilbestrol in utero (uncommon, and primarily older people)

In these populations, Pap testing should begin one after the initiation of sexual intercourse and include annual Pap smears (for at least three years). Colposcopy may be needed even with mild LGSIL changes on a Pap smear, in keeping with guidelines for people who are considered high-risk.

Cervical Cancer Healthcare Provider Discussion Guide

Get our printable guide for your next healthcare provider's appointment to help you ask the right questions.

Doctor Discussion Guide Woman

Treatment

With LGSIL results, it's common to take a watch-and-wait approach. Healthcare providers took a more active approach to low-grade lesions in the past, but research has shown that the practice did nothing to reduce the risk of cancer.

In fact, more aggressive care for people with LGSIL results was more likely to cause harm by exposing people to treatments they don't need.

Since low-grade dysplasia usually resolves on its own, medical treatment may not be needed. However, Pap smears and/or colposcopies may be performed at regular intervals to monitor the dysplasia and ensure it doesn't progress.

If the dysplasia progresses, as determined from findings of a colposcopy or biopsy, treatment may be needed to remove the lesion. Some of these can be performed as an in-office procedure. Treatments include:

  • Loop electrosurgical excision procedure (LEEP), a technique in which an electric current is sent through a wire loop to cauterize and remove abnormal cells
  • Cryotherapy, a technique used to destroy abnormal tissue through freezing
  • Cone biopsy, also known as conization, which involves the removal of a larger, cone-shaped sample of abnormal tissue
  • Laser therapy, using a tiny beam of amplified light to destroy abnormal cells

Treatment during pregnancy is not recommended, even for HGSIL (CIN2 or CIN3) due to the possibility of pregnancy-related complications. You may want to consider asking for a referral to a gynecologic oncologist if that's the case.

Summary

LGSIL is an abnormal result from a Pap test that indicates that some cell changes are taking place. It isn't cancer and often not precancer, but it's something to be aware of and to watch. It's often caused by HPV, and follow-up testing—whether it's another Pap test, HPV test, or HPV typing—is important.

Depending on your individual history and any risk factors, your healthcare provider will talk with you about any next steps. Even if you don't have pre cancer, it's still important to be aware of any cell changes in your body and to identify abnormalities as early as possible with follow-up tests.

Frequently Asked Questions

  • What are the different types of abnormal Pap test results?

    There are: ASC-US (atypical squamous cells of undetermined significance), LGSIL, the more serious HGSIL, ASC-H (atypical squamous cells, cannot exclude HGSIL), and AGC (atypical glandular cells, which raises concern for precancer or cancer).

  • Can LGSIL be a false positive?

    Yes, there are times when a test indicates that a person has a specific disease or condition when they actually do not, which is why a repeat Pap may be done. At the time of the test, there may have been cervical inflammation or an infection that caused the LGSIL result. This is why many providers will wait and see, or do HPV testing.

  • How long does it take HPV to cause abnormal cells?

    It can take years for abnormal cells to be made due to HPV. Cervical cancer is typically slow growing, which is why regular Pap smears need to be done, to catch cell changes in their early stages.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Charlton BM, Carwile JL, Michels KB, Feldman S. A cervical abnormality risk prediction model: Can we use clinical information to predict which patients with ASCUS/LSIL Pap tests will develop CIN 2/3 or AIS? J Low Genit Tract Dis. 2013;17(3):242-7. doi:10.1097/LGT.0b013e3182730fec

  2. National Cancer Institute. LSIL.

  3. National Cancer Institute. Understanding cervical changes.

  4. Fontham ETH, Wolf AMD, Church TR, et al. Cervical cancer screening for individuals at average risk: 2020 guideline update from the American Cancer Society. CA Cancer J Clin. 2020;70(5):321-346. doi:10.3322/caac.21628

  5. American College of Obstetricians and Gynecologists. Abnormal cervical cancer screening test results.

  6. Perkins RB, Guido RS, Castle PE, et al. 2019 ASCCP risk-based management consensus guidelines for abnormal cervical cancer screening tests and cancer precursors. J Low Genit Tract Dis. 2020;24(2):102-131. doi:10.1097/LGT.0000000000000525

  7. National Institutes of Health. Guidelines for the prevention and treatment of opportunistic infections in adults and adolescents with HIV.

  8. Ciavattini A, Serri M, Di Giuseppe J, et al. Long-term observational approach in women with histological diagnosis of cervical low-grade squamous intraepithelial lesion: An Italian multicentric retrospective cohort studyBMJ Open. 2019;9(7):e024920. doi:10.1136/bmjopen-2018-024920

  9. Moffitt Cancer Center. How long does it take cervical cancer to develop?

By Jaime R. Herndon, MS, MPH
Jaime Herndon is a freelance health/medical writer with over a decade of experience writing for the public.

Originally written by Lisa Fayed