Does an Abnormal Smear Result Mean Cancer? ASC-US and LSIL
What an abnormal smear result means, how ASC-US, LSIL and HSIL differ, the cancer risk and the next steps: HPV testing, colposcopy and biopsy.
Short answer: No. An abnormal smear result does not mean you have cancer. Most of these results point to a temporary HPV infection that the immune system can clear on its own, or to cell changes that are easy to treat. "Abnormal" simply means the cells of the cervix show a change that needs a closer look; it is not a cancer diagnosis.
What Does an Abnormal Smear Result Mean?
In a smear test, cells taken from the cervix (the neck of the womb) are examined under a microscope. The result is graded using the Bethesda system, which is used worldwide. The abbreviations on the report can look frightening, but most of them describe the mildest levels.
What Do the Results Mean?
- ASC-US (atypical cells of undetermined significance): There is a small change in the shape of the cells, but the cause is not clear. It may be inflammation, irritation or a temporary infection. This is the mildest form of abnormal result.
- LSIL (low-grade change): Usually a mild cell change caused by a temporary HPV infection. It is also known as mild dysplasia (CIN 1).
- ASC-H (high-grade change cannot be excluded): The cells look atypical and a more significant change cannot be completely ruled out. It is examined more carefully.
- HSIL (high-grade change): A clear cell change is present. There is a high chance of a pre-cancerous lesion (CIN 2 or CIN 3). This is not cancer; it means a change has been caught before it turns into cancer.
- AGC (atypical glandular cells): There is a change in the gland cells of the cervical canal or the womb lining. It is less common but calls for a more thorough work-up.
The Next Step Depends on the Result
Current practice is planned not only from the smear result but also from the HPV test result and your personal risk.
ASC-US
An HPV test is run on the same sample.
- If HPV is negative: The risk is very low. A check-up after 3 years is usually recommended.
- If HPV is positive: The chance of a significant pre-cancerous lesion is around 4 percent. For this reason colposcopy (examining the cervix with a magnifying device) and, if needed, a biopsy (a small tissue sample) are recommended.
LSIL
- If HPV is positive: Colposcopy and, if needed, a biopsy are recommended.
- If HPV is negative: The risk is low, so the test is usually repeated after 1 year.
ASC-H and HSIL
Colposcopy is needed regardless of the HPV result. Especially with HSIL, or when a high-risk HPV type (HPV 16) is found, removing the abnormal tissue from the cervix with a small procedure (LEEP) without waiting for a biopsy may also be an option in some patients. This decision is made together with your doctor, based on age, plans for pregnancy and the findings.
AGC
In every AGC result, colposcopy and sampling from the cervical canal are done regardless of the HPV result. In certain age and risk groups a tissue sample from inside the womb may be added. Repeating the smear alone is not considered enough.
Under Age 25 the Approach Is Different
Cervical cancer is very rare in young women. HPV infections and mild cell changes often clear on their own. Because unnecessary intervention can cause problems such as preterm birth in later pregnancies, a more cautious approach is used in this age group:
- With ASC-US and LSIL, routine HPV testing and colposcopy are not done. Follow-up is by repeating the smear in year 1 and year 2.
- With ASC-H and HSIL, colposcopy is done, but treatment is not given directly without a biopsy.
- With CIN 2, close monitoring (colposcopy and smear every 6 months) may be preferred, because many cases regress on their own in young women. CIN 3 is treated regardless of age.
What Should You Do?
- Don't panic when you get the result; an abnormal result is not an emergency, but it should not be left without follow-up.
- Have the HPV test, colposcopy and any biopsy done on the timing your doctor recommends.
- Don't postpone your next smear or HPV check. Regular screening and catching changes early is an important way to prevent cervical cancer.
Results may vary from person to person in every surgical or interventional procedure. It is recommended that you get detailed advice from your doctor before any procedure.
Frequently Asked Questions
Does an abnormal smear always mean HPV?
It is often related to HPV, but not every abnormal result is caused by HPV. With unclear results such as ASC-US, inflammation or irritation can also be the cause. That is why the HPV test plays an important role in deciding the next step.
Does everyone with ASC-US have to have a colposcopy?
No. If the HPV test is negative, colposcopy is usually not needed and a check-up after a few years is enough. Colposcopy is recommended for people who are HPV positive or found to have a higher risk.
Can I plan a pregnancy after an abnormal result?
For most mild changes, pregnancy plans are not affected. When treatment is needed, the timing varies from person to person; be sure to share your pregnancy plans with your doctor.