A pap smear is a screening tool for cervical cancer. The cervix is the opening to the uterus, and is located at the top of the vagina. The cells on the cervix are continuously changing, and they can develop abnormalities or pre-cancer lesions often referred to as dysplasia. The HPV virus is responsible for these changes occurring. Many women will clear this virus following exposure, but the longer HPV is present the more often it can cause cervical dysplasia, resulting in an abnormal pap smear. In general, pap smear results return in 4 basic ways: Normal, ASCUS (atypical cells of undetermined significance), LSIL (low grade abnormalities) or HSIL (high grade abnormalities).
When a pap smear is normal, there are no signs of cancer or pre-cancer. This type of result allows patients to be on a routine schedule for obtaining pap screening, which is based on their age and individual risk factors. Recommendations may vary anywhere from every 1-5 years. ASCUS pap, the most common identified abnormality, suggests that abnormalities have been identified which may or may not be a sign of pre-cancer. When this type of result returns it is important to know if you are have the HPV virus. When HPV is absent it is unlikely that this represents a precancerous lesion, and typically it is recommended to continue routine pap screening. If HPV is present this carries a higher risk of pre-cancer, and it is recommended to follow-up with colposcopy testing.
LSIL, and HSIL are both results that represent abnormal changes consistent with pre-cancer. These results almost always indicate that HPV is present. LSIL is common, and will many times resolve without treatment. HSIL is more likely to be a lesion that may progress. When either of these results returns, a colposcopy examination is recommended.
Colposcopy is a procedure that allows more detailed evaluation of the cervix and the abnormalities that are present. A magnifying device called a colposcope is used to complete the exam. Patients are positioned similar to the way they were to obtain the pap smear specimen, yet the exam takes longer. The cervix is covered in a solution, most often acetic acid (vinegar) which causes abnormal cells to show up differently through the scope that the normal cells. The physician can then biopsy the areas that show up abnormal to obtain a more specific diagnosis. Remember, the pap smear is only a screening tool. A biopsy allows a small piece of tissue to be evaluated by pathology under a microscope to better identify the amount of abnormality present. Results from a biopsy return as being CIN 1 (mild dysplasia), CIN 2 (moderate dysplasia), or CIN 3 (severe dysplasia).
Recommendations for treatment following colposcopy may vary based on your individual history. CIN 1 will very commonly regress on its own, for that reason most physicians will recommend that a patient with CIN 1 be monitored regularly via pap smear to ensure that this does not progress. Once this has been present for several years your physician may decide to treat by excising the abnormal cells or by freezing them. CIN 2 and CIN 3 will often times be treated more aggressively depending on your age and your pap smear history. Most often treatment is with an excisional procedure called a LEEP (Loop electrosurgical excision procedure). This can be done in a doctor’s office or in an operating room. It is typically done with local anesthesia (numbing the area, yet you are still awake). A thin wire that carries an electrical current is used to shave the abnormal cells off the cervix. Occasionally your doctor may recommend a cold knife cone. This is a procedure done in an operating room under general anesthesia and allows for a more significant amount of tissue to be removed. Both of these procedures can be curative, yet close follow up is required to ensure that the abnormalities do not return.