Liquid-based cytology for primary cervical cancer screening: a multi-centre study

The aim of this six-centre, split-sample study was to compare ThinPrep fluid-based cytology to the conventional Papanicolaou smear. Six cytopathology laboratories and 35 gynaecologists participated. 5428 patients met the inclusion criteria (age > 18 years old, intact cervix, informed consent). Each cervical sample was used first to prepare a conventional Pap smear, then the sampling device was rinsed into a PreservCyt vial, and a ThinPrep slide was made. Screening of slide pairs was blinded (n = 5428). All non-negative concordant cases (n = 101), all non-concordant cases (n = 206), and a 5% random sample of concordant negative cases (n = 272) underwent review by one independent pathologist then by the panel of 6 investigators. Initial (blinded) screening results for ThinPrep and conventional smears were correlated. Initial diagnoses were correlated with consensus cytological diagnoses. Differences in disease detection were evaluated using McNemar's test. On initial screening, 29% more ASCUS cases and 39% more low-grade squamous intraepithelial lesions (LSIL) and more severe lesions (LSIL+) were detected on the ThinPrep slides than on the conventional smears (P = 0.001), including 50% more LSIL and 18% more high-grade SIL (HSIL). The ASCUS:SIL ratio was lower for the ThinPrep method (115:132 = 0.87:1) than for the conventional smear method (89:94 = 0.95:1). The same trend was observed for the ASCUS/AGUS:LSIL ratio. Independent and consensus review confirmed 145 LSIL+ diagnoses; of these, 18% more had been detected initially on the ThinPrep slides than on the conventional smears (P = 0.041). The ThinPrep Pap Test is more accurate than the conventional Pap test and has the potential to optimize the effectiveness of primary cervical cancer screening.     

Comparison of the SurePath liquid-based Papanicolaou smear with the conventional Papanicolaou smear in a multisite direct-to-vial study

BACKGROUND: Split-sample clinical trials for liquid-based Papanicolaou (Pap) smears demonstrated that the liquid-based Pap smear was a safe and effective replacement for the conventional Pap smear. However, clinical intended use of liquid-based technology employs direct-to-vial collection methods. The current study compared the cytologic detection rates of the liquid-based Pap smear with conventional Pap smears in a direct-to-vial study performed at three clinical sites. METHODS: Data from 58,580 prospective SurePath slides and 58,988 historic conventional slides were collected. Results were statistically compared with regard to disease prevalence and adequacy to include biopsy follow-up data for conventional and SurePath tests. RESULTS: The SurePath method was found to provide a statistically significantly greater detection rate for clinically important categories of high-grade squamous intraepithelial lesion (HSIL+) and low-grade squamous intraepithelial lesion (LSIL+) (64% and 107%, respectively; P < 0.00001 for each lesion) compared with conventional slides. The clinical significance of increased cytologic detection using SurePath was supported by biopsy data that essentially demonstrated concordance with regard to biopsy interpretation for HSIL+ (P = 0.9105 at Site 1; P = 1.0000 at Site 2; and P = 1.0000 at Site 3) and LSIL+ (P = 0.6966 at Site 1; P = 0.8052 at Site 2; and P = 1.00 at Site 3). The detection rate of atypical squamous cells of undetermined significance (ASCUS+) was found to be significantly increased (75.12%; P < 0.00001). A statistically significantly lower proportion of unsatisfactory slides using the SurePath test compared with conventional slides was noted (-58%; P < 0.00001). The ASCUS/LSIL+ ratio was found to be reduced overall when using SurePath (-28.9%), regardless of whether the study sites were combined or considered individually. The rate of false-negative results noted with SurePath (10.43%) and conventional slides (12.97%) was essentially equivalent. CONCLUSIONS: The SurePath Pap smear was found to outperform conventional slides in the detection of HSIL+ and LSIL+ cytologic lesions of the cervix and reduced the number of unsatisfactory diagnoses. The HSIL+ advantage for SurePath is not limited to HSIL but appears to extend to carcinoma as well.     

Significance of the Cytological Signs of Human Papillomavirus Infection in Anal Pap Smears of Human Immunodeficiency Virus-Infected Japanese Men Who Have Sex with Men

Purpose: The incidence of invasive anal cancer (IAC) has been increasing among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM). Although cytological diagnosis is the modality of choice for screening cases of IAC, it is associated with lower sensitivity and specificity. Therefore, the present study aimed to evaluate new cytological signs of human papillomavirus (HPV) infection that may contribute to improving anal cytology. Methods: Anal cytology and HPV testing were performed using SurePath liquid-based cytology on samples obtained from 37 HIV-positive Japanese MSM. Subsequently, a histological biopsy based on high-resolution anoscopy was performed in MSM with abnormal cytological findings indicative of atypical squamous cells of undetermined significance (ASC-US) +. Also, anal Papanicolaou (Pap) smears were performed to determine cellularity, presence of dysplastic squamous cells, and other cytological signs of HPV infection. Results: Of the 37 MSM who underwent anal cytology, six tested negative for intraepithelial lesion or malignancy, three cases exhibited ASC-US, 17 exhibited low-grade squamous intraepithelial lesion (LSIL), nine exhibited high-grade squamous intraepithelial lesion (HSIL), and two remained undiagnosed. The anal Pap smears of 28 (96.6%) of the 29 MSM with abnormal cytological findings of ASC-US+ exhibited anal intraepithelial neoplasia (AIN), as revealed by histological biopsy. The median value (minimum–maximum) of the cellularity of anal Pap smears was 12 (0–70.5) nsc/hpf. In 26 MSM with LSIL and HSIL, the median dysplastic squamous cells count was 14 (2–152) dsc/smear and the cytological sign of HPV infection was 11 (2–71) hpv/smear. Of all anal Pap smears that revealed ASC-US+, 96.6% exhibited cytological signs of HPV infection. Compression-positive binucleated cells were the most prevalent among all cytological signs of HPV infection. Conclusion: For anal cytology, instead of considering a small number of dysplastic squamous cells, screening based on cytological signs of HPV infection may be beneficial for improving the diagnosis of AIN.     

The significance of the Papanicolaou smear diagnosis of low-grade squamous intraepithelial lesion cannot exclude high-grade squamous intraepithelial lesion

BACKGROUND: Cervical cytologic specimens that show a low-grade squamous intraepithelial lesion (LSIL) occasionally contain a few cells that are suspicious for, but not diagnostic of, a high-grade squamous intraepithelial lesion (HSIL). In such cases, a diagnosis of LSIL cannot exclude HSIL is rendered. The objective of the current study was to assess the positive predictive value (PPV) for HSIL in follow-up cervical biopsies for these cases. METHODS: One hundred forty-four women with a Papanicolaou (Pap) diagnosis of LSIL cannot exclude HSIL and their follow-up cervical biopsies were reviewed. Results were compared with a control group of 155 women with a Pap diagnosis of LSIL. A subset of biopsies was tested and typed for human papillomavirus (HPV) DNA by polymerase chain reaction amplification using consensus primers followed by restriction fragment length polymorphism analysis. HPVs were scored as low-risk or high-risk types. RESULTS: Women with LSIL cannot exclude HSIL had a higher incidence of HSIL (PPV = 29%) on follow-up cervical biopsy than the control group (PPV = 15%, P < 0.01). In addition, SIL, indeterminate grade was diagnosed in 10% of cervical biopsies in the study group as compared with 4% in controls. Review of Pap smears from the study group showed that there were 3 types of cells suspicious for a high-grade lesion: atypical squamous metaplastic cells (62%), atypical keratinized cells (20%), and dysplastic cells of borderline nuclear-to-cytoplasm ratio (18%). HPV analysis confirmed the presence of high-risk HPV types in the study cases with high-grade cervical biopsies. CONCLUSIONS: Women with a Pap diagnosis of LSIL cannot exclude HSIL appear to be more likely to harbor a high-grade lesion than those diagnosed with LSIL alone. Its use appears warranted. Women with this diagnosis merit appropriate clinical follow-up to exclude HSIL.     

Cytohistologic correlation rates between conventional Papanicolaou smears and ThinPrep cervical cytology: a comparison

BACKGROUND: The ThinPrep Papanicolaou (Pap) test, a liquid-based alternative to the long-used conventional Pap smear, received Food and Drug Administration approval in 1996. The current study is a comparison of the accuracy, as assessed by cytohistologic correlation, of conventional versus ThinPrep Pap smears in a hospital setting. METHODS: A retrospective analysis of all patients who underwent Pap smears (conventional and ThinPrep) and pertinent surgical pathology tissue processed in our department over a 1-year period was undertaken. Tissue diagnoses were grouped into broad general categories to correlate with the Bethesda system. The statistical significance of differences between the two types of Pap test results compared with tissue diagnoses was assessed using a chi-square test with 1 degree of freedom and an alpha value of 0.05. RESULTS: Of the 65,421 Pap smears interpreted during the study period, histologic correlation was possible in 1544 patients. Of those diagnosed as negative (644 conventional and 245 ThinPrep Smears), low-grade squamous intraepithelial lesion (LGSIL) (116 conventional and 114 ThinPrep smears), and high-grade squamous intraepithelial lesions (HGSIL) (142 conventional and 131 ThinPrep smears), there was no statistically significant difference found between the correlation rates of conventional and ThinPrep Pap smear results. However, review of all cases of invasive cervical carcinoma identified during this time period showed the ThinPrep to be less consistent in predicting the presence of invasive carcinoma compared with the conventional Pap smear. CONCLUSIONS: Based on cytohistologic correlation evidence, the ThinPrep Pap test may not be more effective in detecting cervical disease, particularly invasive carcinoma, when compared with the conventional Pap smear.     

Prevalence of High Grade Squamous Intraepithelial Lesion (HSIL) and Invasive Cervical Cancer in Patients with Low Grade Squamous Intraepithelial Lesion (LSIL) at Cervical Pap Smear

Objective: To assess the prevalence and factors associated with a histologic diagnosis of high grade squamous intraepithelial lesion (HSIL) and invasive cervical cancer in patients with low grade squamous intraepithelial lesion (LSIL) cervical pap smear findings. Methods: Medical records (including cytology reports, colposcopic impression, and pathologic results from cervical biopsy, endocervical curetting, cervical conization or hysterectomy) of 226 women with LSIL from conventional cervical pap smears during January 2001 to December 2005, who subsequently underwent colposcopic evaluation at our institution, were reviewed. Results: Mean age of the patients was 39.0 years. The incidences of LSIL, HSIL, microinvasive cervical cancer were 58.8%, 15.0%, 1.3% respectively. No associations were found between age, parity, contraception, anti-HIV or menstrual status and the detection of HSIL/invasive cervical cancer. Conclusion: Approximately 16.3 % of LSIL pap smear cases turn out to be HSIL or invasive cervical cancer from histologic diagnosis.     

Cervical smear interpretations in women with a histologic diagnosis of severe dysplasia: factors associated with discrepant interpretations

BACKGROUND: Because most low-grade squamous intraepithelial lesions (LSIL) regress spontaneously, the appropriate follow-up of women with a cytologic diagnosis of LSIL has engendered discussion. This retrospective study was undertaken to assess the feasibility of limiting colposcopy to women with cytologic interpretations of high-grade squamous intraepithelial lesions (HSIL) in a high-risk population. METHODS: The pathology computer files (including files from January to December 1997) of The University Hospital, University of Oklahoma Health Sciences Center, revealed 197 women whose histologic samples were coded as severe dysplasia. Of these, 138 had a cervical smear interpreted in our laboratory before the colposcopic visit. On review, the tissue samples of 119 women met consensus criteria for severe dysplasia. RESULTS: Original cytologic diagnoses for 119 cytologic smears included 80 (62.7%) that were interpreted as HSIL. After retrospective review, 28 cases with LSIL or less were reclassified as HSIL and were considered to be discrepant for the purpose of this study. Major confounding factors in the original categorization include lack of consistency among the pathologists for the interpretation of metaplastic patterns and specimen adequacy, particularly air-drying artifact. Eleven cases (10.2%) did not have cells identifiable as HSIL because of sampling error and/or severe air-drying artifact. CONCLUSIONS: These results indicate that a substantial number of histologically verified cases of severe dysplasia can have a smear interpretation of LSIL or less. The factors that hampered recognition of the true severity of the lesion in this series were identified and tabulated.     

Identification of progressive cervical epithelial cell abnormalities using DNA image cytometry

BACKGROUND: The objectives of the current study were to compare the capabilities of conventional cervical cytology and of DNA image cytometry (DNA-ICM) in the prediction of progressive or regressive behavior in atypical squamous cells (ASC), low-grade squamous intraepithelial lesions (LSIL), and atypical glandular cells (AGC). METHODS: One hundred ninety-six women with Papanicolaou (Pap) smears that yielded diagnoses of ASC, LSIL, or AGC were included in a prospective cohort study. Slides were classified according to the Bethesda system. DNA-ICM was performed according to the consensus reports of the European Society of Analytical Cellular Pathology. RESULTS: Reference standard verification was available in 108 patients. The rate of DNA aneuploidy in Pap smears increased significantly from cervical intraepithelial neoplasia 1 (CIN1) (54%) and CIN2 (64.3%) to CIN3 or greater (CIN3+) (83.3%) in subsequent biopsies (P < 0.05). Using ASC, LSIL, and AGC as input cytologic diagnoses and >/= CIN2 as the output histologic diagnosis, the positive predictive values (PPVs) for conventional cytology and DNA-ICM were 35.2% and 65.9%, respectively (P < 0.001). The negative predictive value (NPV) of DNA-ICM was 85.0%. When >/= CIN3 was used as the output histologic diagnosis, conventional cytology had a PPV of 22.2%. The PPV and NPV of DNA-ICM were 43.9% and 93.3%, respectively. CONCLUSIONS: The results of the current study confirmed the prognostic validity of DNA image cytometry for differentiation between progressive and regressive lesions in patients with ASC, LSIL, and AGC diagnoses.     

Utility of liquid-based cytology for cervical carcinoma screening: results of a population-based study conducted in a region of Costa Rica with a high incidence of cervical carcinoma

BACKGROUND: In a study using a split-sample design, liquid-based cytology (ThinPrep Processor, Cytyc Corporation, Boxborough, MA) was compared with the conventional Papanicolaou (Pap) smear in Guanacaste, Costa Rica. The study provides the first population-based comparison of the ThinPrep screening technology and includes "gold standard" measures of diagnostic accuracy. METHODS: The population-based study was performed among over 8000 women residing in a Costa Rican province with a high incidence of cervical carcinoma. Conventional smears were prepared and diagnosed in Costa Rica, while the residual material on the sampling device was collected into a liquid preservative and shipped to the U.S., where ThinPrep cytologic slides were prepared and diagnosed. Cytologic diagnoses based on the two techniques, categorized according to the Bethesda System, were compared with a "gold standard" final case diagnosis for each patient, also based on Bethesda terminology, that reflected an integrated interpretation of all available data, including cytology, histology, and cervicography. Results were also compared with the results of HPV DNA detection (Hybrid Capture, Digene Corporation, Silver Spring, MD). RESULTS: ASCUS was the threshold for colposcopy referral. There were significantly more women referred according to this threshold with the ThinPrep slide (12.7%) than with the conventional smear (6.7%, P<0.001). Compared with the final case diagnosis, referral by ThinPrep slides detected 92.9% of cases with high grade squamous intraepithelial lesions (HSIL) and 100% of carcinoma cases. Smears detected 77.8% of HSIL and 90.9% of carcinomas. Thus, ThinPrep cytology was significantly more sensitive in the detection of HSIL and cancer (McNemar test, P<0.001). Adjudication of cases in which the ThinPrep and smear diagnoses disagreed, using the final case diagnoses and the HPV DNA test results as reference standards, suggested that the ThinPrep method was detecting additional true SIL as opposed to false-positives. CONCLUSIONS: In a population-based study of high risk women, ThinPrep cytology demonstrated significantly increased sensitivity for detecting HSIL and carcinoma, with a concurrent significant increase in colposcopy referrals.     

Reducing or eliminating use of the category of atypical squamous cells of undetermined significance decreases the diagnostic accuracy of the Papanicolaou smear

BACKGROUND: The diagnosis of "atypical squamous cells of undetermined significance" (ASCUS) is controversial, not only for the clinical utility of its subcategories (favor reactive vs. favor dysplasia), but for its very existence as an expression of uncertainty. In the current study, the authors investigated the impact of reducing and eliminating this category on the sensitivity and predictive values for detecting squamous intraepithelial lesions (SILs).METHODS: One hundred cervical Papanicolaou (Pap) smears originally diagnosed as ASCUS, all of which had histologic follow-up, were reviewed blindly and reclassified as either negative (within normal limits/benign cellular changes), low-grade SIL (LSIL), or high-grade SIL (HSIL) by 1 reviewer who eliminated ASCUS as a diagnostic possibility entirely. A second reviewer reinterpreted the cases but attempted to use the ASCUS diagnosis (favor reactive or favor dysplasia) sparingly. All histologic diagnoses were reviewed, and an adjudicated final diagnosis was established. Reviewed smear interpretations were correlated with the histologic diagnosis (original, reviewed, and adjudicated). Statistical analysis was performed using the Fisher exact test.RESULTS: Thirty-eight women had histologically confirmed SIL (21 LSIL cases and 17 HSIL cases [including 1 case of endocervical adenocarcinoma]); 31 of these 38 cases originally were classified as ASCUS, not otherwise specified, 1 case was classified as ASCUS favor reactive, and 6 cases were classified as ASCUS favor dysplasia. The reviewer who used the ASCUS diagnosis sparingly reclassified the smears as negative (62 cases); ASCUS, favor reactive (3 cases); ASCUS, favor dysplasia (13 cases); LSIL (19 cases); and HSIL (3 cases). The reviewer who eliminated the ASCUS category reclassified the smears as negative (59 cases), LSIL (29 cases), and HSIL (12 cases). The rate of SIL/HSIL in those cases interpreted as abnormal was 38%/17% originally, 42%/24% with a reduced ASCUS interpretation, and 37%/17% when the ASCUS category was eliminated. In those ASCUS smears that were reclassified as negative, the SIL/HSIL rate was 35%/13% with the reduced ASCUS interpretation and 39%/17% when the ASCUS category was eliminated. The sensitivity for detecting a SIL/HSIL was reduced from 100%/100% for the original ASCUS interpretation to 42%/53% for the reduced ASCUS interpretation to 39%/41% with the elimination of the ASCUS interpretation.CONCLUSIONS: Although in the current study utilization of the ASCUS diagnosis was found to result in a 62% negative or reactive outcome on biopsy, a significant number of patients with SIL were detected (38% in the current series, 17% with HSIL). Despite the improved correlation with negative biopsies, reducing or eliminating the ASCUS diagnosis appears to decrease the sensitivity of the Pap smear significantly and appears to be no better than chance at predicting a diagnosis of SIL on biopsy, including HSIL.     

DNA cytometry confirms the utility of the Bethesda system for the classification of Papanicolaou smears

BACKGROUND: Developed in 1989, the Bethesda System has largely replaced previous classifications of Papanicolaou (Pap) smears from the uterine cervix. The system is binary, dividing smears into two groups - low-grade, squamous, epithelial lesions (LSIL) or high-grade, squamous, epithelial lesions (HSIL). A third category, atypical squamous cells of undetermined significance (ASCUS), is used to classify minimal cellular changes that do not satisfy the criteria for the low- or high-grade categories. This study was designed to confirm the utility of this binary division and to compare the results with another classification system (the Munich II Nomenclature) that is not binary but contains three divisions or grades for dysplasia - low, intermediate, and high. METHODS: Pap smears were obtained from 593 women with a cytologic diagnosis of dysplasia based on the Munich System. Smears were then classified by the Bethesda System into LSIL or HSIL. Patients were followed for 2 years either with biopsy or repeat cytology. The initial smears were restained by the Feulgen method, and ploidy was evaluated by interactive DNA cytometry. RESULTS: Of 241 cases of LSIL, 39% were diploid, 57% polyploid, and 4% aneuploid. Of 352 cases classified HSIL, 4% were diploid, 17% polyploid, and 79% aneuploid. After 2 years of follow-up, 2 of 108 patients who were biopsied and who were originally classified as diploid progressed to cervical intraepithelial neoplasia/carcinoma in situ (CIN/CIS) whereas 109 of 217 patients who were aneuploid and biopsied were found to have CINIII/CIS. CONCLUSIONS: The two divisions of the Bethesda System, LSIL and HSIL, correlated with ploidy as evaluated by cytometry. Aneuploidy was found to be useful to separate cases of HSIL from those of LSIL as defined in the Bethesda System. Because of the binary division, use of a system with three divisions for dysplasia, such as the Munich II Nomenclature, creates a therapeutic dilemma because a single diagnostic category (usually the intermediate grade) may contain both self-limiting and progressive lesions. DNA cytometry of Pap smears was found to be useful as a routine procedure.     

Interobserver variability: comparison between liquid-based and conventional preparations in gynecologic cytology

BACKGROUND: Studies have shown that the ThinPrep Papanicolaou test (TP) increases the detection of epithelial cell abnormalities compared with the conventional preparation. Little is known about the interobserver variability of reporting gynecologic cytology results using the TP preparation and its comparison with results obtained using the conventional method. METHODS: To compare the interobserver variability between the TP method and the conventional method for reporting the diagnoses of gynecologic cytology, 20 pairs of conventional and TP slides (total, 40 slides) that were prepared from split samples were evaluated blindly by 19 cytotechnologists from three different laboratories. Each reviewer was asked to categorize each slide into the following five categories: within normal limits, benign cellular changes, atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesion (LSIL), and high-grade squamous intraepithelial lesion (HSIL). For both conventional and TP preparations, interobserver variability was analyzed using Spearman rank correlation coefficients. The mean correlation coefficients (weak, 0.0-0.4; fair, 0.4-0.7; and strong, 0.7-1.0) between the TP method and the conventional method were then compared. RESULTS: The overall interobserver agreement as well as interobserver agreement within each laboratory was good for both TP and conventional preparations. Based on the set of conventional cervical smears, only one slide that was diagnosed as HSIL had unanimous agreement; whereas, based on the set of TP slides, three slides, including two diagnosed as HSIL and one diagnosed as LSIL, had a unanimous diagnosis. The difference in the interobserver agreement between TP and conventional methods, based on comparing their mean +/- standard deviation correlation coefficients (TP method, 0.84 +/- 0.081; conventional method, 0.82 +/- 0.105; P < 0.001), was statistically significant. CONCLUSIONS: Interobserver agreement in reporting gynecologic cytology using the TP method is good, particularly for squamous intraepithelial lesions, and appears to be superior to the conventional method.     

Cytologic characteristics of abnormal cells in prior "normal" cervical/vaginal Papanicolaou smears from women with a high grade squamous intraepithelial lesion

BACKGROUND: Some cervical/vaginal Papanicolaou (Pap) smears previously diagnosed as normal in women with a high grade squamous intraepithelial lesion (HSIL) are found to contain abnormal cells on retrospective review. This study characterized and quantitated such cells in 100 Pap smears. METHODS: One hundred prior negative Pap smears from 49 women with a newly diagnosed HSIL were rescreened, as were 107 negative Pap smears from 100 women with normal subsequent smears. Cases were assorted randomly so that the rescreener was unaware of the subsequent follow-up. RESULTS: All 12 Pap smears found to contain atypical mature and immature metaplastic cells belonged to the group with a subsequent HSIL (P = 0.001). In addition, 18 of the 100 previously negative Pap smears (18%) had immature metaplastic cells without nuclear atypia compared with 4 of 107 Pap smears (4%) in the control group (P = 0.0007). CONCLUSIONS: This study supports the observations of other authors that atypical metaplastic cells, especially those of the immature type, are associated with HSIL. These cells most likely are HSIL lesional cells, which are not easily recognizable as such. Immature metaplastic cells without atypia also were shown to be associated significantly with HSIL in this study. These cells may be unrecognizable lesional cells or a marker of increased risk for HSIL and deserve further study.     

Observer variation in cytologic grading for cervical dysplasia of Papanicolaou smears with the PAPNET testing system.

BACKGROUND: To assess the interobserver and intraobserver variation of Papanicolaou (Pap) smear screening with the computer-assisted (neural network based) PAPNET Testing System in diagnosing cervical smear abnormalities, results of agreement were compared with the interobserver and intraobserver variation of conventional smear analysis. METHODS: Cervical smears obtained from women in 1996 were reevaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same four investigators, and results were compared with the original screening diagnoses obtained by both methods. RESULTS: The interobserver results for epithelial abnormalities (the degree of agreement between the cytologists), characterized by weighted kappa statistics, were 0.71 (95% CI: 0. 68-0.73) for PAPNET screening and 0.69 (95% CI: 0.66-0.72) for conventional screening. No significant differences were found among the individual results obtained by the four cytotechnologists (intraobserver variation) with conventional screening versus PAPNET reviewing. CONCLUSIONS: Pap smear grading with the PAPNET Testing System has interobserver and intraobserver variation similar to that of conventional screening of Pap smears in routine use. Cancer (Cancer Cytopathol) Copyright 1999 American Cancer Society.     

Prevalence of Abnormal Pap Smears: A Descriptive Study from a Cancer Center in a Low-Prevalence Community

Background and aims: Cervical cancer is the fourth most common cancer in women worldwide and the 13th in Jordan. The cervical smear (Pap smear) is a simple approach to detect pre-cancerous cervical lesions. The aim of this study was to evaluate the prevalence of abnormal cervical smears in women seen at the Early Detection/Community Outreach clinic of King Hussein Cancer Center (KHCC). Materials and Methods: In this retrospective study, reports of routine cervical Pap smears performed in the pathology department at KHCC from January 2007 to December 2016, were reviewed. During this period, a total of 5,529 routine smears were assessed for epithelial abnormalities and histopathological grading. Results: A total of 210 (3.8%) abnormal Pap smears were found, with atypical squamous cell of undetermined significance (ASC-US) reported in 110 (52.4%) cases, atypical glandular cells of undermined significance (AGUS) in 58 (27.6%), low grade squamous intra-epithelial lesion (LSIL) in 27 (12.9%) and high grade intra-epithelial lesion (HSIL) in 13 (6.2%). Only single cases of ASC-H and squamous cell carcinoma were reported. The available biopsies showed benign findings in 70.1% of cases, low grade squamous intraepithelial lesions in 11.5% and high grade squamous intraepithelial lesions in 18.4%. Conclusions: The low epithelial cell abnormality (EPCA) prevalence illustrated in this study argues against introduction of population-based HPV testing and vaccination. It calls for a more cost-effective measures in a country with limited resources, where a more widely available Pap-smear testing might suffice.     

Should women with atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion, receive reflex human papillomavirus-DNA testing?

BACKGROUND: The 2001 American Society for Colposcopy and Cervical Pathology Consensus Guidelines recommend that women who have Papanicolaou (Pap) smears diagnosed as atypical squamous cells (ASC), cannot exclude high-grade squamous intraepithelial lesion (HSIL) (ASC-H) should be referred for immediate colposcopic examination. The objective of this pilot study was to evaluate whether reflex human papillomavirus (HPV)-DNA testing performed on smears diagnosed as ASC-H may obviate the need for immediate colposcopic examination. METHODS: All ThinPrep Pap smears that were diagnosed as ASC-H or atypical squamous metaplastic cells (ASMT) between 2001-2003 and that had HPV-DNA testing and subsequent histologic and/or cytologic follow-up were evaluated. Those smears that were diagnosed as ASMT were reviewed and reclassified under the 2001 Bethesda System as either ASC of undetermined significance (ASCUS) or ASC-H. Smears that were diagnosed as ASCUS were excluded from the study. RESULTS: The study included of 48 smears that were diagnosed as ASC-H. All patients with biopsy-proven HSIL had positive high-risk (HR)-HPV results (100% negative predictive value). Approximately 80% of patients with ASC-H who had biopsy-proven, low-grade intraepithelial lesion on follow-up had positive HR-HPV results. Among the patients who had ASC-H with negative follow-up, 50% had positive HR-HPV results, and 50% had negative HR-HPV results. CONCLUSIONS: Among patients with ASC-H, a negative HR-HPV result was found to be an excellent predictor of the absence of HSIL. The results of this pilot study suggested that HPV-DNA testing may serve as a means to better select which patients with ASC-H on Pap smear should undergo colposcopic examination. This approach potentially may reduce medical costs and eliminate the need for routine colposcopic examination among patients with ASC-H Pap smears.     

Distribution of human papillomavirus types in ThinPrep Papanicolaou tests classified according to the Bethesda 2001 terminology and correlations with patient age and biopsy outcomes

BACKGROUND: A survey of the distribution of human papillomavirus (HPV) types across the spectrum of cervical cytologic categories defined by the Bethesda 2001 guidelines was conducted with the objective of examining how HPV detection by polymerase chain reaction (PCR) analysis may benefit the management of patients who have abnormal Papanicolaou (Pap) test results. METHODS: DNA samples from women with no intraepithelial lesion or malignancy (NLM) (n = 300 samples); atypical squamous cells of undetermined significance (ASC-US) (n = 200 samples); low-grade squamous intraepithelial lesion (LSIL) (n = 200 samples); atypical squamous cells, cannot rule out high-grade squamous intraepithelial lesion (ASC-H) (n = 200 samples); and high-grade squamous intraepithelial lesion (HSIL) (n = 200 samples) were tested for HPV using a modified general primer (GP)5+/GP6+ PCR assay and dot-blot hybridization with type-specific oligonucleotide probes (PCR assay analytical sensitivity: 1-100 copies of HPV, depending on the HPV type, in a background of 100 ng human DNA). RESULTS: HPV was detected in 27% of NLM samples, in 89.5% of ASC-US samples, in 97.5% of LSIL samples, in 93% of ASC-H samples, and in 96.5% of HSIL samples. Thirty-seven different HPV types were identified in total. One or more of 13 high-risk (HR) HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) were detected in 53% of samples that were diagnosed as ASC-US (59.0% of patients younger than age 30 yrs; 45.5% of patients age 30 yrs and older), in 55.5% of samples that were diagnosed as LSIL (60.0% of patients younger than age 30 yrs; 44.0% of patients age 30 yrs and older), in 80% of samples that were diagnosed as ASC-H, and in 87.5% of samples that were diagnosed as HSIL (P < 0.001). HPV-16 was detected in 17.5% of ASC-US samples, in 15.5% of LSIL samples, in 48.5% of ASC-H samples, and in 49.0% of HSIL samples (P < 0.001). Among abnormal smears, HR HPV was significantly more common in women younger than age 30 years compared with women age 30 years and older (P < 0.002). Follow-up biopsy data were obtained for 359 patients. A "benign" biopsy result was recorded for 47 of 64 women (73.5%) with ASC-US, 30 of 66 women (45.5%) with LSIL, 39 of 87 women (45.0%) with ASC-H, and 26 of 142 women (18.0%) with HSIL and was most common in women age 30 years and older (P < 0.0001). Cervical intraepithelial neoplasia (CIN) Grade I (CIN-I) was found in 14.0% of women with ASC-US, in 39.5% of women with LSIL, in 8.0% of women with ASC-H, and in 7.0% of women with HSIL. CIN-II was diagnosed in 9.5% of women with ASC-US, in 13.5% of women with LSIL, in 19.5% of women with ASC-H, and in 24.0% of women with HSIL. CIN-III was identified in 2 women (3.0%) with ASC-US, in 1 woman (1.5%) with LSIL, in 24 women (27.5%) with ASC-H, and in 71 women (50.0%) with HSIL. CONCLUSIONS: HR HPV testing by PCR of samples diagnosed according to the Bethesda 2001 guidelines may benefit the management of patients with ASC-US or patients with LSIL, especially among women age 30 years and older, by allowing exclusion from referral for biopsy of women who are negative for HR HPV types. However, the small numbers of women who had CIN-III detected after a diagnosis of ASC-US or LSIL limited the assessment of test sensitivity.     

Does the interval between papanicolaou tests influence the quality of cytology?

BACKGROUND: It is commonly believed that the sensitivity of Papanicolaou (Pap) tests decreases with a short interval between cytology samplings. To the authors' knowledge, there is only limited evidence to support this belief. METHODS: For 5055 women in the Atypical Squamous Cells of Undetermined Significance (ASCUS)-Low Grade Squamous Intraepithelial Lesion (LSIL) Triage Study (ALTS), the Pap interval was defined as the number of days between the referral Pap smear demonstrating ASCUS or LSIL ("first cytology") and the enrollment liquid-based ("repeat") cytology. The authors investigated the influence of the interval between Pap smears on repeat cytology by examining percentages of abnormal findings, cellularity, and test sensitivity among women diagnosed with histologic grade 3 cervical intraepithelial neoplasia (CIN3) during the 2-year course of the ALTS. In addition, because human papillomavirus (HPV) DNA adjunct testing is now performed, the authors evaluated HPV viral load, which was assayed using residual liquid cytology specimens, in women with CIN3. RESULTS: The Pap interval ranged from 8-30 days in 763 women, 31-60 days in 2317 women, 61-90 days in 1090 women, 91-120 days in 491 women, and 121-184 days in 394 women (mean of 61.3 days; standard deviation of 34 days). Repeat cytologic interpretations of unsatisfactory findings, ASCUS, and high-grade squamous intraepithelial lesion (HSIL) did not appear to vary among the Pap interval groups. However, low-grade cytologic regression occurred with an increasing Pap interval; negative cytology increased from 28.3% (8-30 days) to 41.6% (121-184 days) (P < 0.0001) whereas LSIL cytology decreased (P trend = 0.002). The approximate cellularity of the samples was slightly better in the interval group of 8-30 days (P trend = 0.04). Among women with CIN3, the repeat test sensitivity at a threshold of ASCUS or greater and the HPV DNA viral load was not found to vary by Pap interval (P trend = 0.80 and P trend = 0.36, respectively). CONCLUSIONS: The authors concluded that a short Pap interval (range, 15-120 days) does not significantly affect the quality of liquid-based repeat cytology, nor the viral load tested from a residual liquid-based specimen.     

Papanicolaou smear history in women with low-grade cytology before cervical cancer diagnosis

BACKGROUND: The purpose of the current study was to examine the screening histories of women diagnosed with invasive cervical cancer (ICC) in 2000 who had previous Papanicolaou (Pap) smears deemed to be unsatisfactory or with low-grade findings that did not lead to biopsy. METHODS: A total of 252 Pap smears from 47 women taken between 1992 and 2000 were included in the study; 247 smears were reexamined at the laboratory of origin before the study and all 252 were then reexamined independently by 2 experienced cytotechnicians and 2 cytopathologists. RESULTS: Of the 47 cases of ICC, 35 were squamous cell carcinoma, 10 were adenocarcinoma, and 2 were other types. On reexamination at the laboratory of origin, 24 cases were upgraded and in the study group 27 cases were upgraded to diagnoses requiring biopsy. On reexamination at the laboratory of origin, it was found that the first high-grade squamous intraepithelial lesion (HSIL) could have been diagnosed on average 4.2 years earlier than it was originally (95% confidence interval [95% CI], 3.3-5.1 years). On reexamination by the study group the first diagnosis of HSIL was made in smears dating from 5.4 years before the diagnosis of ICC (95% CI, 4.5-6.2 years). CONCLUSIONS: The study confirms that unsatisfactory and low-grade Pap smears imply a risk of developing high-grade lesions at a later date and shows that in a screening program a subgroup of smears may be diagnosed as unsatisfactory or low grade despite the presence of high-grade findings that are detectable on reexamination.