Papanicolaou tests diagnosed as atypical by a cytotechnologist and downgraded to benign by a pathologist: a measure of laboratory quality

Follow-up of Papanicolaou (Pap) tests diagnosed as atypical squamous cells of undetermined significance (ASCUS) or atypical glandular cells of undetermined significance (AGUS) by a cytotechnologist and downgraded to benign by a pathologist has not been measured. Squamous intraepithelial lesion (SIL) follow-up rates were obtained for Pap tests diagnosed as ASCUS (288) or AGUS (94) and downgraded to benign and for Pap tests diagnosed as repair (231). Statistically significant associations were seen between 7 cytotechnologists and between 7 pathologists and ASCUS, AGUS, downgraded ASCUS, and downgraded AGUS rates. The percentage of downgraded ASCUS cases compared with all ASCUS cases per pathologist ranged from 4.8% to 43.7%. Statistically significant associations between pathologists and SIL follow-up rates for downgraded ASCUS diagnoses were seen. The SIL follow-up rate for repair (7.9%) was similar to that for a downgraded ASCUS (11.0%) or AGUS (7.3%). The parameters of downgraded ASCU and AGUS Pap test interpretations are good quality indicators of individual performance and overall laboratory quality.     

Prevalence and typing of HPV DNA by hybrid capture II in women with ASCUS, ASC-H, LSIL, and AGC on ThinPrep Pap tests

Testing for human papillomavirus (HPV) DNA is now a viable option for the management of women with atypical squamous cells of undetermined significance (ASCUS). The utility of reflexive HPV DNA testing for women with a cytologic diagnosis of atypical glandular cells-not otherwise specified (AGC-NOS), ASCUS subtypes, and low-grade squamous intraepithelial lesion (LSIL) has not been well established. In the present investigation, reflex Hybrid Capture II HPV DNA testing results were evaluated for HPV prevalence and type in 371 women with abnormal cytologic diagnoses of ASCUS-not otherwise specified (ASCUS-NOS), ASCUS-suspicious for low-grade squamous intraepithelial lesion (ASCUS-L), atypical squamous cells-cannot exclude high-grade squamous intraepithelial lesion (ASC-H), AGC-NOS, and LSIL on ThinPrep Pap tests. Positive high-risk HPV DNA was identified in 53.6% of the study samples, including ASCUS-NOS 40.2% ASCUS-L 71.4%, ASC-H 37.5%, LSIL 88.6%, and AGC-NOS 0%. We conclude that reflex HPV DNA testing appears to not be useful for colposcopy triage for cytologic diagnoses of LSIL or AGC-NOS.     

Variance in the interpretation of cervical biopsy specimens obtained for atypical squamous cells of undetermined significance

We sought to determine whether the variability in dysplasia rates in cases of atypical squamous cells of undetermined significance (ASCUS) reflects variability in interpretation of cervical biopsy specimens. In phase 1, 124 biopsy specimens obtained because of a cytologic diagnosis of ASCUS were reviewed independently by 5 experienced pathologists. Diagnostic choices were normal, squamous metaplasia, reactive, indeterminate, low-grade squamous intraepithelial lesion (LSIL), and high-grade squamous intraepithelial lesion (HSIL). The rate of dysplasia ranged from 23% to 51%. All pathologists agreed in 28% of cases. In 52% of cases, the diagnoses ranged from benign to dysplasia. The overall interobserver agreement was poor. In phase 2, 60 cervical biopsy specimens (21 obtained for ASCUS, 22 for LSIL, and 17 for HSIL) were evaluated using the same diagnostic choices. Agreement was better in biopsies performed for HSIL and LSIL compared to those for ASCUS. Intraobserver reproducibility in the interpretation of biopsies performed for ASCUS ranged from poor to excellent. We conclude that variability in the interpretation of biopsy specimens plays an important role in the differences in rates of dysplasia reported for the follow-up of ASCUS.     

Correlation of histopathologic/cytologic follow-up findings with vaginal ASC-US and ASC-H Papanicolaou test and HPV test results

Current American Society of Colposcopy and Cervical Pathology recommendations about human papillomavirus (HPV) triage and further management for atypical squamous cells are pertinent to cervical Papanicolaou (Pap) tests. There are limited data on HPV detection in vaginal liquid-based cytology (LBC) specimens. The aims of this study were to determine whether adjunctive high-risk (HR)-HPV testing is useful for disease risk assessment in women with vaginal atypical squamous cells of undetermined significance (ASC-US) and atypical squamous cells, cannot exclude HSIL (ASC-H) Pap results. We identified 1,125 ASC-US and 36 ASC-H vaginal Pap results with HR-HPV testing. Of the cases, 244 (21.7%) ASC-US and 21 (58%) ASC-H were HR-HPV+. Among ASC-US HR-HPV+ cases, 47.8% had a squamous intraepithelial lesion (SIL) compared with 4.7% of HR-HPV- cases. Among ASC-H HR-HPV+ cases, 75% (12/16) had SIL compared with 31% (4/13) in HR-HPV- cases. Our results indicate that HPV triage testing is a reasonable and cost-effective approach for women with ASC-US vaginal Pap results and also a useful option for women with ASC-H vaginal Pap results.     

Utility of P16 expression and Ki‐67 proliferation index in ASCUS and ASC‐H pap tests

Current cervical screening uses a combination of cytology and high‐risk human papillomavirus (HR‐HPV) analysis in cases of atypical squamous cells of undetermined significance (ASCUS) and atypical squamous cells cannot exclude high‐grade intraepithelial lesion (ASC‐H). These diagnoses are subject to interobserver variability and HR‐HPV analysis can be limited by sampling inadequacy. This study correlates immunoexpression of P16 and Ki‐67 in residual cervicovaginal material against cytology category and HR‐HPV status. Eighteen pap tests were selected: 8 ASCUS, 4 ASC‐H, and 6 controls (2 LSIL and 4 HSIL). Digene Hybrid Capture II test was used to detect HR‐HPV. The cytospins were stained for P16/Ki‐67. Pap tests, P16, Ki‐67, HR‐HPV result and available biopsies were correlated. P16 expression correlated with HR‐HPV status in 15/17 cases. Discordant cases (1 ASCUS and 1 ASC‐H) were +P16/–HR‐HPV. Ki‐67 correlated with HR‐HPV in 8/15 cases. Discordant cases were +HR‐HPV/– Ki‐67 (HSIL, LSIL, and ASC‐H one each), and –HR‐HPV/+Ki‐67 (3 ASCUS, 1 LSIL, 1 ASC‐H). Two cases were + P16/+ Ki‐67/– HR‐HPV. None were ‐ P16/– Ki‐67/+ HR‐HPV. Histologic follow‐up in 13 cases varied from benign to CIN III. Two cases of +P16/ – Ki‐67/– HR‐HPV had benign cervical biopcies. Although a small sample size, our findings show a utility for adjunct P16/ Ki‐67 in addition to HR‐HPV testing in cases of squamous atypia when HR‐HPVs are non‐detected due to low DNA copies, or missed lesions in cervical biopsies. Diagn. Cytopathol. 2014;42:576–581. © 2013 Wiley Periodicals, Inc.     

Atypical glandular cells of undetermined significance (AGUS): cytopathologic features, histopathologic results, and human papillomavirus DNA detection.

We intensively reviewed 137 smears initially classified as atypical glandular cells of undetermined significance (AGUS) to refine cytological criteria for evaluating these cases, evaluate histological outcomes, and assess the value of human papillomavirus (HPV) DNA testing in management. Consenting, nonpregnant study participants were identified from a cohort of 46,009 women receiving routine Pap smear screening in a managed care setting. Colposcopy was performed on all women, and at least one histological sample was obtained from each. Review diagnoses were assigned to smears and biopsy specimens by two separate panels of pathologists. DNA testing for cancer-associated HPV types was performed on rinses of cytological samplers after a smear and thin-layer slide had been made. On review, 47 (34%) smears were reclassified as negative, 44 (32%) as AGUS, 30 (22%) as atypical squamous cells of undetermined significance (ASCUS), and 16 (12%) as squamous intraepithelial lesions (SIL). The 19 smears interpreted as high-grade intraepithelial lesions on review included 13 high-grade SIL (HSIL), two HSIL with AGUS, favor neoplastic (endocervical adenocarcinoma in situ [AIS]), and four AGUS, favor neoplastic (AIS). Review histological diagnoses were negative in 105 (77%), squamous or glandular atypia in four (3%), low-grade SIL (LSIL) in nine (7%), HSIL in 12 (9%), AIS in five (4%, including two with concurrent HSIL), and endometrial carcinoma in one (1%). HPV testing identified 11 (92%) of 12 women with histologically confirmed HSIL and all five with AIS (100%). A high-grade intraepithelial lesion or carcinoma is detected in approximately 14% of women with community-based diagnoses of AGUS who are referred for immediate evaluation. Use of refined cytological criteria and HPV DNA testing may permit improved management of women with AGUS.     

"ASCUS, rule out HSIL": cytologic features, histologic correlates, and human papillomavirus detection.

Risk factors, cytologic and histopathologic features, and human papillomavirus (HPV) detection associated with 75 cervical smears classified as atypical squamous cells of undetermined significance, rule out high-grade squamous intraepithelial lesion (ASCUS, rule out HSIL) were reviewed. Cases were identified in a pathology panel review of material collected from 1953 women participating in a 5-year prospective study of HPV infection and squamous intraepithelial lesions at Kaiser Permanente, Portland, Oregon, sponsored by the National Cancer Institute. Initial abnormal smears diagnosed as ASCUS, rule out HSIL by one panelist or diagnosed as ASCUS by one pathologist and as HSIL by another were included. The 75 ASCUS, rule out HSIL smears identified were examined again by two pathologists after the study. These cases were compared with cases of ASCUS, not otherwise specified (ASCUS, NOS) and HSIL identified in the same group of 1953 women. Findings in ASCUS, rule out HSIL included tissue fragments (21%); atypical immature metaplasia (17%); atypical mature metaplasia (15%); small atypical cells (9%); and atypical repair (4%). A final patient classification of HSIL, reflecting all available data, was assigned to 11 (24%) of 46 women with ASCUS, rule out HSIL and to 1(1%) of 80 women with ASCUS, NOS in the original review (P < .001). Detection of oncogenic HPV types at diagnosis in ASCUS, rule out HSIL; ASCUS, NOS; and HSIL was similar, but data were unavailable for many subjects. Among women not tested at diagnosis, enrollment testing (1 to 4 years earlier) revealed that HPV detection in women with ASCUS, rule out HSIL was intermediate in frequency between ASCUS, NOS and HSIL. These data suggest that ASCUS, rule out HSIL is a distinct diagnosis from ASCUS, NOS because it is more often associated with an underlying HSIL. Consequently, women with ASCUS, rule out HSIL should be referred for colposcopic examination.     

Smears diagnosed as ASCUS: interobserver variation and follow-up

The purpose of this study was to apply atypical squamous cells of undetermined significance (ASCUS) criteria from the Bethesda System for Reporting Cervical/Vaginal Cytologic Diagnoses (TBS) to the rescreen of cases previously diagnosed as ASCUS, to compare initial and rescreen diagnoses, and to analyze agreement with follow-up (cytology or histology). Two cytotechnologists (S.B. and M.J.M.) and one cytopathology fellow (M.A.) rescreened 632 cervicovaginal specimens diagnosed as ASCUS between June 1, 1992-December 31, 1995. Age and LMP were provided. Rescreen diagnoses were categorized as within normal limits (WNL), ASCUS, low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), or carcinoma (CA). Complete agreement was found in 200 specimens (32%): 31 (15%) WNL; 91 (45%) ASCUS; 77 (38.5%) SIL; and one (0.50%) CA. Follow-up revealed no abnormality in 67% of the cases reclassified as WNL, 49% of the cases reclassified as ASCUS, and 48% of the cases reclassified as squamous intraepithelial lesions (SIL). SIL was found in 29% of cases reclassified as WNL, 29% of specimens rediagnosed as ASCUS, and 34% of cases reclassified as SIL. Partial agreement was found in 391 specimens (62%). In 41 specimens (6%), rescreeners were in complete disagreement, and follow-up revealed 9/41 (22%) SIL or worse; 21/41 (51%) WNL; and 4/41 (10%) inconclusive. Applying established criteria, 14% (91/632) of cases diagnosed as ASCUS resulted in complete agreement, and 30% (190/632) resulted in partial agreement. Follow-up of cases initially diagnosed as ASCUS revealed SIL or CA in 30% of cases. ASCUS is a significant diagnosis warranting careful patient follow-up.     

Subclassifying atypical squamous cells in Thin-Prep cervical cytology correlates with detection of high-risk human papillomavirus DNA.

Recent studies have proposed subclassifying ASCUS into "favor reactive" (ASFR), "not otherwise specified" (ASNOS), and "favor squamous intraepithelial lesion (SIL)" (ASFS). This study explored the reproducibility of these diagnoses with Thin-Prep cytology and their association with high-risk human papillomavirus DNA (HRHPV). Three pathologists and 1 cytotechnologist with 2 to 25 years of experience reviewed 144 Thin-Prep (Cytyc, Boxborough, MA) specimens previously diagnosed as normal, ASFR, ASNOS, ASFS, and SIL. Interobserver reproducibility was computed with the kappa statistic. The original laboratory diagnosis was compared with the presence of HRHPV types. Interobserver reproducibility for a normal or SIL diagnosis was very good (kappa = .68 and .63). Reproducibility for ASFR, ASNOS, and ASFS ranged from poor to fair (kappa = .21, .19, and .32). In a weighted analysis, kappa values for ASFR/ASNOS and ASFS/SIL were .36 and .62, respectively. HRHPV-positivity for preparations originally diagnosed as N, ASFR, ASNOS, ASFS, and SIL were 5.7%, 8.8%, 17.4%, 47.8%, and 54.5%, respectively. The difference in index of HRHPV for either N or ASFR and ASFS or SIL was significant (P < .001). Reproducibility for ASCUS is generally poor, but better reproducibility is obtained by combining ASFS with SIL and, to a lesser degree, ASNOS with ASFR. ASFS and SIL confer a similar index of HRHPV and merit similar management. ASFR may be managed with cytologic follow-up; but this may depend upon the individual laboratory. HPV testing, in conjunction with cytologic and biopsy follow-up, appears useful for estimating the significance of ASCUS subgroups in laboratory practice.     

Accuracy and reproducibility of telecytology diagnosis of cervical smears. A tool for quality assurance programs

We randomly selected 50 cervical smears (benign, 14; atypical squamous cells of undetermined significance [ASCUS], 5; low-grade squamous intraepithelial lesion [LSIL], 10; high-grade squamous intraepithelial lesion (HSIL), 12; squamous cell carcinoma, 6; adenocarcinoma, 3) and captured 1,181 digital images (518 MB) at a maximum resolution of 1,600 x 1,200 pixels and transmitted them by e-mail. Diagnosis of glass slides and digital images was done independently in a double-blind manner by 3 pathologists and 3 cytotechnologists, commencing with the diagnosis of digital images followed by diagnosis of glass slides 3 months later. The procedure was repeated after 3 months. Diagnoses were recorded as benign, ASCUS or atypical glandular cells of undetermined significance, LSIL, HSIL, squamous cell carcinoma or adenocarcinoma, and "inadequate for diagnosis." Diagnostic accuracy and interobserver reproducibility were analyzed using an intraclass correlation coefficient (ICC), which revealed good interobserver agreement for the first (0.72) and second (0.64) glass slide diagnoses and the first (0.72) and second (0.60) digital image diagnoses. The kappa values for intraobserver variation between first and second glass slide diagnoses and first and second digital image diagnoses showed moderate to excellent agreement. Digital images are suitable substitutes for glass slides; telecytology can be used as an alternative method for the cytologic diagnosis of cervical smears, particularly in quality assurance programs.     

Reporting of atypical squamous cells,cannot exclude a high‐grade squamous intraepithelial lesion (ASC‐H) on cervical samples: Is it significant?

"Atypical squamous cells, cannot exclude a high-grade squamous intraepithelial lesion (ASC-H)" is a new diagnostic category in the 2001 Bethesda nomenclature system for cervical cytology. The purpose of this 7-mo retrospective study (March 1, 2002-September 30, 2002) was to evaluate the significance of ASC-H on cervical Thin Prep Pap Tests. During this period, 25 (0.27%) of 9,214 Pap Tests were diagnosed as ASC-H, 22 of which resulted in either follow-up cervical biopsies and/or cervical cones, and which formed the basis of this study. Tissue specimens (22 cases) were negative in 5 cases (23%) and positive in 17 cases (77%). Of the positive specimens, there were 2 (12%) low-grade squamous intraepithelial lesions (LSIL) and 15 (88%) high-grade squamous intraepithelial lesions (HSIL). Of the 22 cases, ASC-H diagnoses included immature/atypical squamous metaplasia vs. a squamous intraepithelial lesion (SIL) in 19 (86%) cases, and tight clusters of small cells with a high nuclear to cytoplasmic ratio in 3 (14%) cases. The results of this study indicate that the reporting of ASC-H on cervical samples does lead to the detection of HSILs in a significant number of cases (68% in this study). Therefore, further evaluation of the patient is warranted.     

An analysis of factors that influence the ASCUS/SIL ratio of pathologists

In pursuit of physician-specific performance data in cytology, we have been calculating the ASCUS/SIL (atypical squamous cells of undetermined significance/squamous intraepithelial lesion) ratio of cytopathologists (CPs) and providing confidential feedback every 6 months. At the same time, thin-layer technology was introduced as an alternative to conventional smears. Thus we analyzed factors that may influence the ASCUS/SIL ratio, particularly the effect of periodic feedback on outliers (defined by a professional benchmark). For 3 years, the mean ASCUS/SIL ratio for all CPs decreased significantly from 2.92 to 1.87. There was great variability in the mean ASCUS/SIL ratio among 12 CPs (range, 1.11-5.89). Of the 6 CPs who worked continuously during this time, 2 showed a statistically significant decrease in their ASCUS/SIL ratio, including the CP with the highest ratio; 1 showed a significant increase. The mean ASCUS/SIL ratio did not correlate well with years of CP experience or with individual annual case volume. The ASCUS/SIL ratio of some CPs can decrease significantly over time. Whether it was due to feedback or the introduction of thin-layer preparations could not be determined.     

Qualification of ASCUS. A comparison of equivocal LSIL and equivocal HSIL cervical cytology in the ASCUS LSIL Triage Study

Cytologic detection of high-grade squamous intraepithelial lesions (HSILs) is critical to cervical cancer prevention. Therefore, identifying "equivocal HSIL" (ASCUS [atypical squamous cells of undetermined significance]-H) may be useful. Accordingly, we compared findings associated with "equivocal low-grade SIL" (ASCUS-L), ASCUS-H, and HSIL using data from the ASCUS LSIL (low-grade squamous intraepithelial lesion) Triage Study. The frequency of oncogenic human papillomavirus (HPV) DNA detection and underlying lesions cervical intraepithelial neoplasia (CIN) 2 or worse or CIN 3 or worse in women with ASCUS-H was intermediate between that of ASCUS-L and HSIL. Oncogenic HPV DNA was associated with 85.6% of ASCUS-H ThinPreps and 69.8% of ASCUS-H smears. Histopathologic lesions CIN 2 or worse were associated with 40.5% of ASCUS-H ThinPreps and 27.2% of ASCUS-H smears (mostly CIN 3). Nevertheless, numerically more lesions CIN 2 or worse were preceded by ASCUS-L than by ASCUS-H because ASCUS-L was more common. ASCUS-H is an uncommon interpretation that derives clinical usefulness from its high positive predictive value for lesions CIN 2 or worse.     

Atypical squamous cells,cannot exclude high grade intraepithelial lesion (ASC‐H): Does HPV matter?

The role of human papillomavirus (HPV) in cases diagnosed as atypical squamous cells, cannot exclude high squamous grade intraepithelial lesion (ASC-H) in cervical specimens is not well established. The objective of this study is to evaluate the role of HPV status in cases of ASC-H in a major cancer center. One hundred thirty-two patients with a diagnosis of ASC-H were identified over a 4-yr period in our institution. Forty-four of 132 cases were evaluated for high-risk HPV and had biopsy follow-up. The positive predictive value (PPV) of ASC-H for high-grade squamous intraepithelial lesions overall was 32% while PPV of ASC-H with associated HR HPV was 42%. This increase was statistically significant with P = 0.003 and suggest that HPV testing might be useful to increase the PPV of ASC-H.     

The value of duplicate slides on atypical squamous cells, cannot exclude high-grade intraepithelial lesion

Atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H) category was added to the 2001 Bethesda System. ASC-H accounts for a small percentage (0.2-0.6%) of abnormal Pap smears and includes heterogenous group of lesions. There are more high-grade cervical lesions (30-50%) in ASC-H than ASC-US (10-15%). An accurate Pap diagnosis is crucial for appropriate patient follow-up and treatment. A total of 43 consecutive ASC-H cases were collected from October 2007 to March 2008, and all duplicate and the original slides were reviewed blindly at the end of the study. On review of the duplicate Pap slides, 18 cases had diagnostic SIL cells (15 HSIL, 2 LSIL with ASC-H, and 1 LSIL). The duplicate slides could have potentially changed 18 (41.9%) ASC-H diagnoses to a more definitive SIL diagnosis. On review of the original Pap slides, 8 of these 18 cases also had HSIL cells. Twenty-one follow-up cervical biopsies (21/43, 48.8%) showed 12 CIN 2/3, 4 CIN 1, 1 VAIN 1, 2 cervical polyps, 1 negative for dysplasia, and 1 insufficient for diagnosis. The CIN 2/3 rate was 57.1% (12/21) based on the original ASC-H Pap diagnosis. The CIN 2/3 rates were 80% (8/10) with SIL cells on duplicate slides and 36.4% (4/11) without SIL cases on duplicate slides. Our study suggested that duplicate slides were very useful for further classification of ASC-H, but other ancillary tests might be necessary for some cases. We propose a systematic approach using combined duplicate slides and reflex HPV testing to further classify ASC-H.     

The clinical significance of "squamous intraepithelial lesion of indeterminate grade" as a distinct cytologic category

The histologic and/or cytologic follow-up of 127 cases of cervical lesions termed "squamous intraepithelial lesion of indeterminate grade" (SIL) on Papanicolaou (Pap) smears by the 2001 Bethesda System was compared with 150 control cases of low-grade SIL (LSIL), high-grade SIL (HSIL), and atypical squamous cells, cannot exclude HSIL (ASC-H). A follow-up diagnosis of cervical intraepithelial neoplasia (CIN) 2 or higher was identified in 22.8% of SIL cases, which was 2.6 times higher than LSIL, 3 times lower than HSIL, and 1.5 times lower than ASC-H. A follow-up diagnosis of CIN 1 was identified in 31.5% of SIL cases, which was 2 times lower than the LSIL group, 1.5 times higher than the ASC-H cases, and 1.8 times higher than the HSIL group. We found that 22.0% of cases diagnosed as SIL were followed up by Pap smears rather than colposcopy and biopsy, compared with about 1% of LSIL and HSIL cases. Because SIL cases have a significant risk of harboring CIN 2 or greater, we recommend follow-up by colposcopy and biopsy.     

Reflex high-risk human papilloma virus DNA test is useful in the triage of women with atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion

This study is aimed to investigate the role of reflex high-risk human papilloma virus (HPV) DNA testing as an alternative triage method to colposcopy for women with atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) on Papanicolaou (Pap) tests. Reflex HPV DNA testing using Hybrid Capture II method was carried out on 88 women with ASC-H diagnosed by Thin Prep Pap test. Correlation with follow-up biopsies was available on 42 of these patients. The reflex HPV DNA test showed an overall positive rate of 67% and negative rate of 33% in 88 patients with ASC-H. Using age 30 as the cut off point, the positive rate had increased to 83.3% (35/42) in patients 30 yr or younger, while the positive rate for patients older than 30 yr had decreased to 52.2% (24/46). Follow-up colposcopic biopsy results were available in 35 of 59 HPV-positive women, which revealed 15 (43%) high-grade squamous intraepithelial lesions (HSIL), 12 low-grade squamous intraepithelial lesions (LSIL), and 8 negative for dysplasia. In 7 HPV-negative patients, the follow-up biopsies showed no evidence of HSIL or LSIL. Correlation between clinical risk factors and the HPV results demonstrated no significant differences in HPV positivity between the high-risk and low-risk patients. The high sensitivity (100%) and negative predictive rate (100%) in detecting HSIL in our study provide strong evidence that, instead of automatic referral to colposcopy, reflex HPV DNA testing may be used as an alternative triage method for women diagnosed with ASC-H on Thin Prep Pap test, especially for women older than 30 yr of age.     

Long-term outcome and relative risk in women with atypical squamous cells of undetermined significance.

Few studies have compared long-term follow-up and risk for invasive cancer in women with atypical squamous cells of undetermined significance (ASCUS). We conducted a 6-year review of pathology files for 651 women in whom ASCUS had been diagnosed in 1992. Data collected included patient demographics, follow-up diagnoses, time between follow-up examinations, and procedures performed. At follow-up, high-grade squamous intraepithelial lesions (HSIL) had developed in 9.0% of the women, and invasive cancer in none. Previous cervical history did not affect risk for an HSIL. Although the average time to first follow-up was 6.18 months, in 20.9% of the women the diagnosis of HSIL was not established until after 2.0 years. For individual pathologists, the percentage of HSILs ranged from 0% to 18.8%. Thus women with ASCUS who are followed up regularly are at low risk for development of invasive cancer.     

Atypical epithelial cells and specimen adequacy: current laboratory practices of participants in the college of American pathologists interlaboratory comparison program in cervicovaginal cytology

CONTEXT: The Bethesda System for reporting cervical/vaginal cytologic diagnoses introduced terminology for atypical squamous and glandular cells and categories for specimen adequacy. OBJECTIVES: To analyze current laboratory reporting practices and compare trends to previous surveys. DESIGN: Questionnaire surveys were mailed to 2000 laboratories in 1996 and 1997. PARTICIPANTS: Laboratories enrolled in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology. MAIN OUTCOME MEASURES: Laboratory policies, criteria, and reporting rates for Bethesda System categories. RESULTS: The 1996 specimen adequacy survey had 1166 respondents, and 768 laboratories returned the 1997 questionnaire focusing on atypical squamous cells of undetermined significance (ASCUS) and glandular cells of undetermined significance (AGUS). Nearly all laboratories (92%) routinely reported specimen adequacy, an increase from the 66% rate in 1991. The median rate for unsatisfactory specimens was 0.5% (mean 0.95%), and the median rate for the satisfactory but limited category was 5.8% (mean 9.3%). The Bethesda criteria for designating a specimen unsatisfactory were used by more than 90% of laboratories. Nearly all laboratories (97%) used the term ASCUS in 1997, and more than 80% of laboratories used the Bethesda criteria for this category. Median reporting rates for epithelial abnormalities were as follows: ASCUS, 4.5%; AGUS, 0.3%; low-grade squamous intraepithelial lesion (SIL), 1.6%; and high-grade SIL, 0.5%. The median ASCUS/SIL ratio was 2.0, with 80% of laboratories reporting ratios between 0.64 and 4.23. The median ASCUS rate and ASCUS/SIL ratio were higher than 1993 survey results. Nearly all laboratories attempted follow-up studies on patients with abnormal cytology results, and midsized laboratories achieved the highest rates of follow-up. Median rates of abnormalities following an ASCUS or AGUS diagnosis were 20% and 15%, respectively. Laboratory respondents commonly used written recommendations in ASCUS/AGUS reports. CONCLUSIONS: Most laboratories that responded to the surveys had adopted Bethesda terminology and criteria for specimen adequacy and ASCUS/AGUS. Reporting rates for SIL and adequacy categories have remained stable, but median ASCUS rates and ASCUS/SIL ratios are higher than in 1993. The AGUS category is reported infrequently, but can be associated with significant pathology.     

Enlarged squamous cell nuclei in cervical cytologic specimens from perimenopausal women ("PM Cells") : a cause of ASC overdiagnosis

We studied the appropriateness of interpreting squamous cells with enlarged, smooth, bland nuclei in perimenopausal women ("PM cells") as atypical squamous cells (ASCs). Papanicolaou smears (Paps) from 100 women (40-55 years old) with a cytologic interpretation of ASC of undetermined significance (ASCUS) and human papillomavirus (HPV) testing or a biopsy within 6 months were reviewed by 2 observers without knowledge of the biopsy diagnosis or HPV results. Cases in which both reviewers agreed that the Paps were diagnosed more properly as "negative for intraepithelial lesion or malignancy" were compared with cases of "true ASCUS," using histologic squamous intraepithelial lesion and/or a positive high-risk HPV test as a positive outcome (abnormal follow-up). Of 100 cases, 28 were reclassified as benign by both observers. In 15 of these, the original ASCUS interpretation was based on cells with bland nuclear enlargement (2-3 times the area of intermediate cell nuclei), smooth nuclear membranes, and fine chromatin. Abnormal follow-up was identified in 1 (7%) of 15 benign cases but in 30 (42%) of 72 true ASCUS cases (P = .023). PM cells are a significant cause of ASC overdiagnosis in women 40 to 55 years old. Cervical Paps with cells no more atypical than these can be interpreted safely as negative for intraepithelial lesion or malignancy.