Pap Smears Save Lives

Since I became a gynecologist, about every two years I have had the terrible task of having to tell a woman that she has cancer of the cervix. To date, not one of these women has met the criteria that would, according to medical books, place her in a high risk group for this disease. High risk patients include women with multiple sexual partners, a history of sexually transmitted diseases, a suppressed immune system and smokers.

My patients with cervical cancer have been a diverse group with ages ranging from 21 to 92 years. Most of them have been married or monogamous with no past history of sexually transmitted diseases. What my patients have had in common is that all of them had gone more than two years without a pap smear.

The great tragedy of this is that cervical cancer is almost completely preventable with annual pap smear screening. The pap smear is performed by collecting a sample of cells from the cervix with either a cotton swab or a tiny brush and spreading them on a microscope slide. The slide is then sprayed with a fixative and sent to a laboratory where it is stained and examined under the microscope by a cytopathologist.

Pap smears allow us to detect pre-cancerous changes of the cervix that can be cured over 98% of the time with simple outpatient procedures that are relatively painless and rarely take more than 10 or 15 minutes to perform.

 Cervical cancer is believed to be caused by the Human Papilloma Virus, the same virus that causes venereal warts. This virus is so common that, in one study, it was found to be present in 50% of sexually active college students. The virus may lie dormant in a woman's body for years or even decades before inducing any type of cellular abnormality that can be identified under the microscope. The progression from cervical dysplasia to cancer is generally fairly slow. It often takes several years for a lesion to evolve from mild dysplasia, the earliest pre-cancerous change identified with pap screening, to invasive cancer. There are, however, several subtypes of the virus that may transform the cells of a woman's cervix from normal to cancerous in a much shorter time span, some in as little as one or two years.

 In those women who do not develop venereal warts, there are no physical symptoms to serve as early warning signs of cervical dysplasia, so Pap smear is the major means of early detection.

 Pap smears are not perfect. Labs report up to a 20% false negative rate but with annual screening, abnormalities that are missed one year stand a good chance of being picked up the next year. This is why the American College of Obstetrics and Gynecology continues to recommend annual screening. Some groups, including the American Cancer Society, have recommended pap smear screening be done only every three years in certain low risk populations after they have had normal exams for three consecutive years. The problem here is that, should a false negative reading occur, (one where there is an abnormality that is missed) the abnormality that has been missed may have time to evolve into an invasive cancer in three more years. Annual exams offer a much safer window of opportunity for picking up early abnormalities.

Cervical cancer is one of very few cancers that can be prevented almost all of the time. But this can only be done with vigilant screening programs.

Another situation that I encounter frequently is that women who have had a hysterectomy believe they no longer need to have pap smears or pelvic exams. This is not true for a number of reasons.

1.)Dysplasia and cancer may develop in the vagina or on the vulva.

2.)If the hysterectomy was performed to treat uterine cancer or cervical cancer, the primary site of recurrence is in the base of the vagina. These recurrent cancers can be discovered by pap smear.

3.)If the patient’s ovaries have not been removed then an annual pelvic exam offers the best chance we have of picking up ovarian abnormalities. Even if  these women do not need an annual pap smear, they should have annual pelvic exams.