What is a Pap Smear?
The test is named after the Greek physician Georgios Papanikolaou, who invented the test. Even though a Pap test sometime can show signs of infections, it is only used to detect abnormalities and changes in the cervix that are cancer or can develop into cancer. It is not a test for sexually transmitted diseases.
The current recommendations in the USA say that women over 21 who are sexually active should have a Pap smear done every two years. Women over 30 who have low risk for developing cervical cancer and had three consecutive normal Pap smears can have the test done a little less frequently, the recommendation is every three years. However, if a women has had abnormal Pap smears, or who has other risk factors like an infection with HIV (the virus that causes AIDS), a weakened immune system due to an organ transplant, chemo or radiation therapy or chronic therapy with corticosteroid for inflammatory diseases, or who was exposed to diethylstilbestrol (DES) in the womb should have Pap smears more often.
Women who have had a complete hysterectomy for other reasons than cervical cancer do no longer need this test, but should still have regular pelvic exams. If a woman had a partial hysterectomy that preserved the cervix, she should continue to have regular Pap smears. If a complete hysterectomy was done to remove cervical cancer, Pap smears need still to be done on a regular basis to test for the reappearance of the cancer.
There is also a test called anal Pap test that is similar to the regular Pap smear, but it looks for cancerous cells in the anus and rectum.
How is a Pap Smear performed?
A Pap test is performed as part of a pelvic exam. During the pelvic exam a small tool called speculum is inserted into the vagina to widen it and give the physician access to the outer part of the cervix, called ectocervix. A plastic spatula and/or a small brush are inserted into the vagina through the opening of the speculum and cells from the cervix are collected. The cells are then put into a tube with tissue culture medium. That is a solution that contains nutrients and can keep the cells alive until they can be examined in a lab by a pathologist.
The Pap smear itself is not painful at all, but many women experience slight discomfort during the pelvic exam.
It can take several weeks before the test results are back in your doctor’s office. If the test showed abnormalities further testing might be necessary. One frequently used test is a colposcopy. For this test, which is the examination of the vagina and the cervix with a special microscope called a colposcope, a speculum is again inserted into the vagina. The physician then looks into the vagina with the colposcope. The colposcope will not be inserted into the vagina. Another test that is very commonly performed after a Pap smear showed precancerous or cancerous abnormalities in the cervix, is a cervical biopsy. In a biopsy, a larger amount of tissue than the few cells taken during the Pap smear, is removed from the cervix and examined by a pathologist.
Sometimes the Pap smear needs to be repeated, because the results of the first test are inconclusive. This can happen when the pathologist is not sure whether some of the cells are abnormal and a repeat is done to confirm the presence of abnormal cells. A second Pap test might also be necessary, if the first test did not collect enough cells from the cervix. If there is too much blood left in the vagina, because the test was performed too close to the last menstrual bleeding, it might have to be repeated too, as the blood will make it impossible for the pathologist to see the cervical cells clearly. If an infection was present when the Pap smear was done, a repeated Pap smear after the infection has healed, will be necessary.
Read More: Endometrial/Uterine Cancer
What are the possible abnormalities detected with a Pap smear?
The Pap smear can detect abnormal changes in the cells of the cervix that are precancerous. Precancerous cells can develop into cancer cells and cause cervical cancer. The Pap test can also detect cervical cancer cells. The precancerous changes in the cervical cells that are called cervical intraepithelial neoplasia (CIN) or cervical dysplasia are usually caused by infections with human papilloma viruses (HPV). Since these are sexually transmitted, having a regular Pap smear is important for women who are sexually active. The Pap smear can also sometime show signs of other infections. However, the Pap smears purpose is to look for cancerous and precancerous cells, and does not replace specific test for sexually transmitted diseases. Sometimes, the test can also find abnormalities that stem from the inside of the uterus, i.e. from the endocervix and the endometrium.
That a Pap smear is abnormal does not mean that there were precancerous or cancerous cells present in all cases. The abnormal Pap smear simply means that the cells contained in the sample did not look normal. In some cases that can be caused by the use of spermicidal creams, other vaginal cream or douching within 48h before the test. In these cases, the Pap smear has to be repeated and the second test might yield a normal result.
Cervical cancer can be cured, if it is detected early. With regular Pap smears abnormal precancerous growths might be detected before they develop into cancer, which will make treatment even easier. Pap smears are particularly important in the early detection of cervical cancer, because cervical cancer rarely ever causes symptoms in its early stages. The symptoms it might cause are unspecific and to many women not very worrisome like e.g. slight bleeding between periods, or after sexual intercourse and douching. An abnormal vaginal discharge can also be a symptom of cervical cancer or a vaginal infection. This should be checked by a professional and treated accordingly. Women who are experiencing these symptoms sometimes take them lightly as long as they are not associated with pain. However, these symptoms should be taken seriously as cervical cancer does not cause pain in its early stages.