Chapter 10: Pap Test Results
On completion of this section, the learner will be able to: 1. Identify how Pap test results are interpreted and the reasons for normal and abnormal results. 2. Describe the appropriate follow‐up for each Pap result using the CervixCheck Screening Guidelines.
Learning Objectives The Bethesda System1 Guidelines for the management of women are based on the Bethesda System, which is the recommended standard for use in Canada, and by CervixCheck. Specimen Adequacy The two categories of specimen adequacy are:  Unsatisfactory for Evaluation  Satisfactory for Evaluation Unsatisfactory for Evaluation Unsatisfactory for Evaluation indicates that:  The slide was processed and examined but was unsatisfactory for evaluation because of obscuring factors (excessive RBC’s, WBC’s or mucous) or insufficient epithelial cells or cytolysis. The reasons the Pap test was considered Unsatisfactory for Evaluation will be given in the report (e.g. too few cells were collected or the cells on the smear were spread too thickly). Unsatisfactory Pap tests are mostly due to:  cervical sampling errors, or  specimen collection issues (refer to chapter 9 to review Pap test sampling techniques). Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 1 The following table identifies and describes each reason for Unsatisfactory Pap test results: Unsatisfactory due to: Description Mainly endocervical cells only Excessively thick cell preparation for adequate cytological evaluation Acellularity Only cells from the endocervix are visible. Be sure to use a cytobrush and a spatula. The sample was likely not spread correctly across the slide, such that the sample appears lumped together or “thick.” Not enough cells were collected to interpret the sample. Insufficient epithelial Not enough cells were collected to interpret the cells sample. Obscuring inflammation There is a presence of infection and/or necrosis (dying cells, usually due to disease) in the sample. Obscuring blood The presence of blood in the sample makes it inadequate for interpretation. Excessive cytolysis Cells have broken down from drying, or pressure. Spray more quickly after specimen is collected. Lubricant or other Other foreign material, i.e. lubricant exists on the foreign material slide making it difficult to read the sample. Mechanical distortion The sample is inadequate for interpretation due to broken down cells (i.e. from too much pressure applying the sample to the slide). Excessive drying artifact The sample is inadequate for interpretation due to cells drying. Broken slide The sample could not be interpreted because the slide is broken. Other Possible Reasons for Unsatisfactory Pap Tests2 Woman  Intercourse within 24 hours of Pap test  Douching or vaginal medication used 24 hours before Pap test  Menses  Body habits (obesity may make the procedure more difficult)  Infection Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 2 HCP 
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Did not sample far enough into endocervical canal to obtain endocervical/metaplastic cells Did not allow slide to dry before packaging Delay in applying fixative/use of outdated fixative Lack of cellular exfoliation (instrument choice) Lack of clinical information obtained Satisfactory for Evaluation2 The diagnostic categories are:  Negative for Intraepithelial Lesion or Malignancy  Epithelial Cell Abnormality  Other Negative for Intraepithelial Lesion or Malignancy Pap tests interpreted as Negative for Intraepithelial Lesion or Malignancy indicate that the test was satisfactory and that the woman should continue with routine screening. Epithelial Cell Abnormality Pap tests interpreted as Epithelial Cell Abnormality include both those that:  represent cervical carcinoma, and  have changes considered to indicate increased risk of cervical carcinoma. Changes indicative of increased risk for cervical carcinoma are reported as:  Atypical Squamous Cells (ASC) - ASC‐US: Atypical Squamous Cells of Undetermined Significance - ASC‐H: Atypical Squamous Cells, Cannot rule out High‐Grade Squamous Intraepithelial Lesion (HSIL)  Low‐Grade Squamous Intraepithelial Lesion (LSIL)  High‐Grade Squamous Intraepithelial Lesion (HSIL) - Includes Carcinoma in‐Situ  Atypical Glandular Cells (AGC)  Adenocarcinoma in Situ (AIS)  Squamous Carcinoma Adenocarcinoma (Other malignancy) Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 3 Other Results The Transformation Zone The presence of squamous metaplastic cells and/or dysplastic cells and/or endocervical cells is generally regarded as evidence of adequate sampling of the transformation zone. If the components of the transformation zone are absent in a satisfactory Pap test, do not repeat the Pap test. The decision to repeat the Pap test is based on the cytology diagnosis and not the presence or absence of transformation zone cells.1 Screen according to the cytology result. Rejected Specimen A specimen may be rejected for one of the following reasons:  The specimen slide is improperly labeled  Failure to identify the slide with the woman’s name when she is a non‐
Manitoba resident or, if for any other reason has not been issued a PHIN  Discrepancy of information between the specimen and the requisition  The slide is broken beyond repair  The slide is received without accompanying requisition Endometrial Cells3 Cervical cytology is not a good diagnostic assessment for endometrial cancer. The presence of apparently benign endometrial cells in women over 40 years indicates an increased risk for endometrial cancer and therefore endometrial assessment. Endometrial cells reported in women less than age 40, rarely have associated significant endometrial pathology. Because menopausal status, hormonal therapy, menstrual data and clinical risk factors are often unknown, endometrial cells should be reported in all women from the age of 40 onward. Endometrial biopsy should be performed if the woman is:  over 40, has irregular bleeding and no history of hormones or IUCD  over 40, and her menstrual history is unknown, or  Post‐menopausal with no history of HRT Screening Guidelines The following table shows CervixCheck recommendations for follow‐up of all Pap test results: Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 4 Jan 2013 Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 5 Limitations of Pap Test Results False Negative Results1 A false negative result occurs when the Pap test fails to detect an abnormality that is present on the cervix. False negatives occur because either:  abnormal cells are not present on the slide due to limitations of cervical sampling and Pap test preparation, or  the laboratory did not identify abnormal cells in the Pap test. Cervical cancer screening is not completely sensitive. The Pap test has a false negative rate that varies widely (13‐70%) in published studies and may be higher for a single client visit. Repeat screening at regular intervals is necessary to provide adequate lifetime protection from cervical cancer. Most sexually active women should be screened every three years. Important Information Talking to Women about Abnormal Pap Test Results Abnormal Pap test results are common. One in four women will have an abnormal Pap test result in her lifetime.4 The psychological impact of having an abnormal result varies between women. How a HCP communicates with the woman about her abnormal result can impact her perspective and subsequent psychological response. Below are some suggestions for how to communicate with a woman about her abnormal Pap test result:  Inform the woman that her Pap test result is abnormal, meaning that the Pap test has detected abnormal cell changes on the cervix. Abnormal cell changes are caused by the HPV virus.  In rare circumstances, and often over a long period of time, abnormal changes caused by HPV can become cancerous.  Reassure the woman that her abnormal result is most likely not cancer.  Normalize HPV. Reassure the woman that HPV is very common. Three out of four people will have at least one HPV infection in their lifetime. Most infections will disappear on their own.  Use “Pap tests: Understand your results” (available at TellEveryWoman.ca/resources) brochure to help explain the meaning of the result and the recommended follow‐up.  Ensure the woman understands the information you have provided her and clarify any misunderstanding. Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 6 
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Remind the woman that most women who have abnormal Pap test results and who have follow‐up tests and/or treatment will never get cancer of the cancer. Address any fears/barriers that may prevent her from following up on the recommended course of action. Women can contact CervixCheck, CancerCare Manitoba for more information. o TellEveryWoman.ca o 204‐788‐8626 or toll free 1‐866‐616‐8805 Colposcopy5 Women with high‐grade and persistent low grade/unsatisfactory Pap tests results are referred to colposcopy. Colposcopy is a technology that has been used for several decades to identify sub‐clinical abnormalities of the cervix. The cervix is magnified through a binocular scope with a high intensity light. This allows for the identification of abnormalities based upon:  Epithelial density (white epithelium)  Vascular patterns (punctation, etc.) Using these parameters, an area of abnormality can be identified in order to direct a tissue biopsy by one of the following methods:  Laser surgery (uses an intense, narrow beam of light to remove abnormal cells)  LEEP (loop electro surgical excision procedure; an electrical wire loop is inserted into the vagina where abnormal tissue is removed)  Cone biopsy (the removal of a cone‐shaped piece of tissue) To see colposcopy images, as well as carcinoma and other abnormalities of the cervix, please see the Pap Test Learning Module video presentation on “Carcinoma of the Cervix.” Recommended Reading CervixCheck Resources Screening Guidelines Abnormal Results/Colposcopy (pamphlet) Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 7 Solomon, D., Davey, D., Kurman, R., Moriarty, A., O'Connor, D., Prey, M., Raab, S., Sherman, M., Wilbur, D., Wright, T., & Young, N. (2002). The 2001 bethesda system terminology for reporting results of cervical cytology. JAMA, 287(16): 2114‐2119. The College of Physicians and Surgeons of Manitoba. (2013). Manitoba laboratory standards. Winnipeg: Manitoba. 1. How are Pap test results interpreted? Chapter 10
2. What are reasons for Unsatisfactory Pap tests? Self‐Test 3. What are the CervixCheck management steps for all cytology results? 4. Why does a false negative result occur?
References 1 Manitoba Cervical Cancer Screening Program. (2009). MCCSP screening guidelines. Manitoba: CancerCare Manitoba 2
Manitoba Cervical Cancer Screening Program. (2002). Pap smears: A resources guide for Manitoba health professionals. Manitoba: CancerCare Manitoba 3
Manitoba Cervical Cancer Screening Program. (2008). Policy manual. Manitoba: CancerCare Manitoba. 4
Manitoba Cervical Cancer Screening Program. (2008). Rates of cervical dysplasia. Manitoba: CancerCare Manitoba. 5
From Alberta Medical Association. (2003). Guideline for screening for cervical cancer: Revised. Adapted with permission. Pap Test Learning Module for Health Care Providers Chapter 10 ‐ 8