Tuesday, February 1, 2011

What Causes Abnormal Pap Results

One of the most frightening phone calls a woman can get from her gynecologist is one telling her that her Pap smear results are abnormal. What does this mean? Is it cancer? What causes it? These are all typical questions that a woman who has had an abnormal Pap smear might ask. A Pap smear is a screening test. An abnormal result doesn't often mean cancer, just changes in cervical cells that if untreated, could one day lead to cancer.


History


The Papanicolaou smear, or Pap smear, was introduced in the 1940s. The Pap smear is used to detect abnormal cells that might develop into cervical cancer, if left untreated. According to the American Cancer Society, the cervical cancer death rate declined by 74 percent between 1955 and 1992. This drop is attributed to the use of the Pap smear.


Abnormal Pap Results


A Pap smear screens for changes in the cells of the cervix, which can have a number of causes. The test is specifically used to screen for precancerous changes because of HPV, but an abnormal result also can be caused by infection, sexual activity, medication and other viruses.


Atypical Squamous Cells


The most common abnormal Pap result is atypical squamous cells of undetermined significance (ASCUS). This is not cancer; ASCUS shows inflammatory changes that are likely because infection from bacteria or yeast or reparative changes in the cervix. Viruses such as trichomoniasis and herpes simplex cause changes in cervical cells. Inflammatory changes can be caused by the cervix repairing itself from sexual activity, by birth or by an IUD. Medications for menopause and some lubricants can also cause changes to cervical cells. All of these changes can be detected by a Pap smear and are considered benign, since none lead to cancer. Women with this result may be retested in a few months.


Squamous Intraepithelial Lesion (SIL)


Squamous intraepithelial lesion (SIL) results will be low-grade (LSIL, CIN-I, mild dysplasia), high-grade (HSIL, CIN-II, moderate dysplasia) or carcinoma in situ (CIN-III, severe dysplasia). Someone with a result of LSIL will have a colposcopy within 4 weeks to determine the extent of the cell changes. This result is not cancer, but it is likely to turn into cancer, if left untreated. HSIL is also not yet cancer, but a woman with this result will typically have further testing done right away. Someone who has CIN-III does have cancer, but it is limited to the cervix. The cure rate is high.


HPV


HPV is the leading cause of abnormal Pap results. Over 100 types of HPV exist. About 30 types are transmitted sexually through touch and are known as genital HPV. Most genital HPV types cause no harm, some cause genital warts, while others cause changes to the cells of the cervix that do not cause cancer. Thirteen types of HPV that cause abnormal changes to cervical cells could lead to cervical cancer. When a Pap smear is abnormal, a DNA test to identify the presence of these 13 strains of HPV can be done.

Tags: cervical cells, changes cervical, changes cervical cells, abnormal result, cause changes, cervical cancer, cancer left