A diagram of the female reproductive system, including the cervix.
Atypical squamous cells of undetermined significance (ASCUS) is a mildly abnormal reading that can occur when a woman has a Pap test. Abnormal squamous cells are sometimes found, but their presence does not clearly indicate a cancerous or precancerous state. This type of abnormal reading could mean that the patient will need more tests or monitoring of the Pap test results in the coming years to make sure there are no signs of cervical cancer. In more than 80% of cases, ASCUS does not represent a finding of cancer, but caution is advised.
Atypical squamous cells can be discovered during a routine Pap test.
The very reading, “atypical squamous cells of undetermined significance,” says a lot about what the test communicates. The fact that ASC has “undetermined meaning” really says it all. The laboratory analyzing the test cannot tell the significance of the reading because its meaning is unknown.
Any reading that may have a small indication that cervical cancer could develop suggests further testing. A woman with the ASCUS finding may be asked to be screened for the human papillomavirus (HPV) because many forms of HPV have been linked to cervical cancer. Not all women get this test, especially if they have active vaginal infections from an identified source that could be responsible for the ASCUS result, or if they are pregnant, when abnormal readings become quite common.
The Pap test scrapes cells from the cervix to check for abnormal growth.
There are so many things that cause an atypical squamous cell of undetermined significance result that doctors may decide not to do much. In addition to pregnancy, menstruation when you have had a Pap smear or normal sexual activity just before a Pap smear can cause irritation to the cells of the cervix and produce thin squamous cells. This last cause is one of the reasons why women are asked not to have intercourse on the eve of a pelvic exam.
Normal sexual activity just before a Pap test can produce thin squamous cells, so women are advised not to do this before the exam.
Given these normal causes of ASCUS, many doctors simply choose to repeat the Pap test the following year to see if abnormal results persist. On the other hand, if a woman is at a reasonably increased risk of cervical cancer, a finding of atypical squamous cells of undetermined significance may suggest a more extensive form of cervical examination and biopsy called a colposcopy. This can better assess the cervix by examining it microscopically, and then the doctor can take small samples of any areas that seem worrisome.
Menstruation during the Pap test can lead to the production of thin squamous cells.
In most cases, a lab result of atypical squamous cells of undetermined significance doesn’t mean much, although it does require some follow-up. Most women can get this result once and never have another abnormal Pap smear. It is still important to recognize the potential importance of ASCUS and to follow your doctor’s recommendations for further treatment or testing.
