The Pap test is the best way to find conditions that may lead to cervical cancer. By treating precancer, cervical cancer can usually be avoided. The Pap test may find problems before you are aware that anything is wrong. If you have an abnormal Pap test, do not panic.
Results are most often classified by a system developed by the National Cancer Institute (NCI).
- Normal: This result means that only normal cells are seen.
- ASCUS (Atypical squamous cells of undetermined significance): This result means that the cells may not be normal. It is hard to tell exactly what is wrong with them.
- Squamous intraepithelial lesion (SIL): This result means that the cells that were tested show certain distinct changes. These changes are also called dysplasia or cervical intraepithelial neoplasia (CIN). There are three grades of each of these. SIL is classified as low grade or high grade. Low-grade SIL includes mild dysplasia (CIN 1) and changes linked to HPV. HPV is a virus that may cause genital warts. Some types have been linked to cervical cancer. High-grade SIL included moderate and severe dysplasia (CIN 2 and 3) and carcinoma in situ (CIS). CIS, although not a true invasive form of cancer, is a precancer that must be treated.
- Cancer: This result means that the cells have progressed beyond dysplasia (CIN) and have become invasive.
Any abnormal findings or a finding of ASCUS showing that cells may not be normal requires further tests. This may be as simple as a repeat Pap test in a few weeks or months. Sometimes your doctor will do an exam called colposcopy to decide if you need treatment. Colposcopy is done in your doctor's office with a special microscope called a colposcope. By looking at the cervix through a colposcope, your doctor may be able to see the changes that cause the abnormal Pap test result. Colposcopy may help the doctor decide whether a cervical biopsy needs to be done and if so, what kind. A biopsy removes some of the abnormal cells for further study. It is usually done in the doctor's office or clinic. There are several types of biopsies. Your doctor may perform one of the following:
- Punch biopsy: A small sample of the cervix is removed with a special instrument.
- Endocervical curettage: A sample is removed from the inside part of the cervix with a small instrument shaped like a spoon.
- Endometrial biopsy: A small amount of the tissue lining the uterus is removed.
- Loop electrode excision procedure (LEEP): A thin wire loop carrying an electric current is used to remove abnormal areas of the cervix.
- Cone biopsy: A cone-shaped wedge of tissue is removed from the cervix.
Because abnormal areas are removed, sometimes a biopsy will also serve as a method of treatment.