Get Adobe Flash player

The cervix (or neck) of the uterus is more prone to develop cancer than any place else in the female body. Indeed, one hundred years ago, cervical cancer was the leading cause of death in women. It remains one of the leading killers of women in undeveloped countries. Fortunately, the development of the Pap smear reversed this trend. In fact, the Pap smear is the single most effective cancer screening test ever discovered. That means it has the power to detect more pre-cancerous conditions and cancers than any other currently available test. Because the Pap smear is effective in detecting pre-cancerous conditions, cervical cancer is usually prevented from developing at all, due to several different treatment options available today. Those of us who are cytology professionals are very proud of this exemplary record and endeavor to maintain its effectiveness in cancer prevention.

The patient, physician and Pap smear lab all contribute to a successful Pap smear screening test. Since the Pap smear is a screening test (compared to a definitive diagnostic test) efforts must be made to ensure that all components of the test are adequately performed.

The Patient: It is essential that the patient return for annual screenings or whatever interval recommended by the physician. The benefits of screening do not fall on unscreened women.

The Physician (the pre-analytic step): It is their responsibility to adequately collect the specimen from a well visualized cervix. Furthermore, they must collect the specimen from the part of the cervix most prone to cancer development (the transformation zone). In addition, they must harvest a substantial number of cells upon which the microscopical analysis is performed. Too few cells present are unlikely to provide a sensitive result. Also, it is their responsibility to provide suitable sample preservation and identification so that the cells present can be visualized. Finally, they must act upon the Pap smear interpretation.

The Pap Smear Lab (the analytic step): It is our responsibility to maintain accurate identification of the samples, concentrate the cells when appropriate and stain them properly for microscopic examination. Then we look for any and all abnormal cells that may be present. This is a difficult and tedious process, similar to looking for “the needle in the haystack”. When we encounter abnormal (“atypical”) cells, then we must interpret the degree of abnormality. In other words, just how abnormal are these cells anyway? Finally, we put our interpretation into our classification of abnormality and report our findings to the physician (or nurse practitioner). We maintain these reports indefinitely. Later if a biopsy is performed, we can then compare the Pap smear to the biopsy if incongruent findings are encountered.

The Pap smear is not a perfect test: Obviously with such a long process, errors can occur at any step along the way. For this reason, the overall effectiveness of the Pap smear is approximately 90%. That means that 10 out of 100 Pap smears fail to detect a significant abnormality. Most failures of detection currently are for pre-analytical reasons, which means that the abnormal cells for whatever reasons do not make it onto the Pap smear. Because screening Pap smears involves two steps (detection of abnormality and interpreting abnormality) and can be tedious and difficult (because the vast majority of cells present are normal), errors may also occur at this step. For this reason Pee Dee Pathology recommends at least annual Pap smears, despite other screening intervals you may have heard about.
In order to increase the sensitivity of the Pap smear, reduce errors of detection and to improve our interpretation, we use the ThinPrep ™ method technology. This technology is proven to increase the detection of the most important pre-cancerous condition and so we totally recommend the ThinPrep™ Pap test for routine use. In addition, we continuously evaluate and use enhanced technology when it is appropriate, in order to improve the Pap smear.

Resources (Links will open in a new window):