Endocervical glandular neoplasia and its mimics in ThinPrep Pap tests. A descriptive study

Atypical glandular cells in Papanicolaou test: Which is more important in the detection of malignancy, architectural or nuclear features?

OBJECTIVE

Atypical glandular cells (AGCs) in Pap (Papanicolaou) smears are uncommon but may represent various benign and malignant lesions. The aim of this study was to evaluate the AGC incidence in Pap smears, analyse the relationship between AGC and malignancy, and reveal the importance of architectural and nuclear features observed cytologically in malignancies.

METHODS

Patients diagnosed with AGC on the basis of cervicovaginal cytology between May 2011 and July 2018 were included in this study. All slides were retrospectively reviewed and subclassified according to the Bethesda 2001 classification system. The cytomorphological features observed in the smears were recorded. Cytohistological correlations were evaluated, and the significant clinicopathological findings for malignancy were determined.

RESULTS

Of 87 536 Pap smears, 195 (0.22%) had AGC results and 156 had tissue follow-up. Among the 156 smears with AGC, 80 (51.3%) were diagnosed as AGC-NOS (atypical glandular cells, not otherwise specified) and 76 (48.7%) as AGC-FN (atypical glandular cells, favour neoplastic). Follow-up biopsies revealed benign pathologies in 49 cases (31.4%) and malignant pathologies in 107 (68.6%). The rate of malignancy observed in AGC-FN cases (89.5%) was higher than the rate of malignancy in AGC-NOS cases (48.8%). Among the cytomorphological features, nuclear irregularity, presence of macronucleoli, feathering, loss of polarity, papillary pattern, and three-dimensional formation were found to be significant indicators of malignancy.

CONCLUSION

As AGC in Pap smear was associated with a clinically significant diagnosis in 68.6% of the cases in our study, we suggest that all patients with AGC should undergo further clinical assessment.

Role of fractal dimension in distinguishing benign from malignant endometrial clusters in liquid-based cervical samples

INTRODUCTION

Exfoliated endometrial cells are often seen as hyperchromatic crowded groups (HCGs) in cervical samples. It is challenging for the cytopathologists to discriminate between HCGs of benign and malignant endometrial cells. Fractal dimension (FD) analysis has proved to be a useful tool in discriminating between different types of cell groups in previous studies.

AIMS

This study was conducted to evaluate the utility of FD for differentiating between benign and malignant endometrial HCGs, in liquid-based cervical samples.

METHODS

Two groups of cervical samples, with subsequent histopathology, were selected: Group A: 30 cases with benign endometrial HCGs; and Group B: 39 cases with malignant endometrial HCGs. Image J, NIH and FracLac software were used for selecting and measuring the FD of the HCGs. Student t-test was used for statistical analysis.

RESULTS

The mean FD for benign endometrial HCGs (1.066943 ± 0.0699) was significantly lower than that of the malignant endometrial HCGs (1.086271 ± 0.05121; P = .001). Using receiver operator characteristic curve analysis, we determined that an FD cut-off value of 1.01 would yield sensitivity of 90.3%, specificity of 26.1%, positive predictive value of 47.3% and negative predictive value of 78.6%.

CONCLUSION

The measurement of FD of HCGs in cervical samples can serve as a useful screening adjunct to differentiate malignant from benign HCGs, owing to its high sensitivity. However, in view of its low specificity and positive predictive value, we recommend that cases labelled as malignant by the FD value be confirmed for malignancy by other methods.

Detecting uterine glandular lesions: Role of cervical cytology

Background:

The sensitivity of cervical cytology for detection of glandular lesions is reported to be low. We conducted this study to assess the diagnostic accuracy of cervical Papanicolaou (Pap) smears for uterine glandular lesions and to compare the diagnostic utility of conventional and liquid-based cytology (LBC) smears for glandular lesions.

Materials and Methods:

Archived histopathology records of all cases reported as endocervical and endometrial adenocarcinoma in the study period were identified and the available corresponding Pap smears (in preceding 1 year) were retrieved. In addition, the Pap smears reported as glandular cell abnormalities (GCA) during the same study period were retrieved. The overall prevalence of GCA, sensitivity, and specificity of Pap smears for the detection of GCA was calculated. The diagnostic accuracy of conventional and LBC smears for the diagnosis of GCA was also compared.

Results:

The prevalence of GCA in our study was 0.32%. The overall specificity of Pap smears for the diagnosis of GCA was 60.8%, this was not significantly different between conventional and LBC smears (P = 0.4). The overall sensitivity of Pap smears for the detection of GCA was 41.8%; LBC smears had significantly better sensitivity as compared to conventional smears for the detection of endometrial as compared to endocervical adenocarcinoma (P < 0.05).

Conclusions:

The prevalence of GCA in Pap smears is low. The specificity of Pap smears, for diagnosis of GCA, was found to be moderate. However, the overall sensitivity of Pap smears for the detection of GCA was low, though better for LBC as compared to conventional smears.

Atypical glandular cells (AGC): ThinPrep Imaging System (TIS), manual screening (MS), and correlation with Hybrid Capture 2 (HC2) HPV DNA testing

OBJECTIVE

The aim of the study was to determine if the ThinPrep Imaging System (T1S) improves the positive predictive value (PPV) of atypical glandular cell (AGC) diagnosis for identifying HPV-related squamous and/or glandular lesions over manual screening (MS), and if human papilloma virus (HPV)-DNA testing improves the diagnostic yield.

MATERIALS AND METHODS

85 ThinPrep cervical cytology specimens with a diagnosis of AGC by TIS (n = 51) and MS (n = 34) were retrieved. The diagnoses were correlated with corresponding histologic follow-up and high risk (HR)-HPV testing results.

RESULTS

The PPV of AGC by TIS and MS for HPV-related squamous lesions were similar. In the MS group, more cases of glandular pathology were identified, however only three represented adenocarcinoma in-situ (AIS), and the remaining ten were endometrial carcinomas (EMCA).

CONCLUSIONS

TIS and MS are comparable in the detection of AGC representing squamous histology and the addition of HPV DNA testing does not differentially improve performance. Although the MS group harbored more glandular pathology, the differences in the detection of AIS were not statistically significant.

Weeding atypical glandular cell look-alikes from the true atypical lesions in liquid-based Pap tests: A review

The purpose of this review is to identify features that separate atypical glandular cells (AGC) associated with glandular neoplasia from its mimickers, both benign and neoplastic. We reviewed cases of AGC diagnosed on liquid-based Pap tests (LBP) for which corresponding histological follow-up was available. A review of the literature for similar studies in LBP tests was also conducted. We find that certain benign mimics can be reliably separated from AGC, but recommend caution in attempting to increase specificity at the risk of losing sensitivity. Although accounting for only a small percentage of diagnoses AGC require a thorough clinical evaluation, including colposcopy. Most cases are ultimately found to be benign. When evaluating smears suspicious for AGC, it is important to examine the subtle features which make truly atypical cells discernible from their numerous benign mimickers.

Rapid review of liquid-based smears as a quality control measure

The objective of this study was to investigate the effectiveness of a standardized method of rapid review (RR) of monolayer preparations for the identification of abnormalities, the presence of an endocervical component and infectious agents. A total of 200 ThinPrep (Cytyc, Boxborough, MA) slides representing the spectrum of abnormalities commonly encountered in cervical/vaginal cytologic specimens was retrieved from archive. The study set comprised 129 cases within normal limits (WNL); 36 low-grade epithelial abnormalities (LGEA); 28 high-grade epithelial abnormalities (HGEA), including 2 endocervical adenocarcinomas in situ (AIS) and 7 carcinomas. Eighteen false negative (FN) cases were also included for study. Originally missed on initial review, these cases were found to be abnormal on quality control review (17 LGEA; 1 AIS). Commonly encountered infectious agents were represented and included Candida albicans, Trichomonas vaginalis, herpes simplex virus, and Actinomyces. The slides were reviewed using a standardized method of RR (turret technique, for 60 sec) by three experienced screeners masked to the original reference diagnosis. Median sensitivity for LGEA was 70% (range, 67-72%); HGEA, 69% (range, 54-80%); and FN, 65% (range, 56-78%). Specificity remained high, median specificity for LGEA was 95%; HGEA, 97%; and FN, 100%. There was no significant overcalling of any diagnostic category. The chi-square test at P < 0.05 showed no significant difference between RR and full manual rescreen of the ThinPrep smears in this study. While no statistical difference was proven, the sensitivity measurements for all categories of abnormality were moderate due to the high proportion of atypical cases included into the study set. Abnormalities on the monolayer preparations frequently displayed fewer, smaller groups of disaggregated cells with rounded cytoplasmic outlines that were difficult to discern on RR. Interobserver variation was noted. Monolayers with a paucity of diagnostic cells and those displaying subtle nuclear atypia were often overlooked.

P16INK4A positivity in benign, premalignant and malignant cervical glandular lesions: a potential diagnostic problem

A wide array of immunohistochemical markers have been evaluated with respect to their specificity in staining dysplastic cervical cells in cervical biopsies and cervical cytological smears. However, there is still a significant demand for better biomarkers to identify neoplastic cervical glandular and squamous epithelial cells precisely. The CDKN2A gene, located on chromosome 9p21, encodes the tumour suppressor protein, p16INK4A, which decelerates the cell cycle by inactivating CDK4 and CDK6. The aim of this study was to compare and contrast the expression pattern of p16INK4A in benign and neoplastic glandular lesions and tubo-endometrioid metaplasia. All cases in each category displayed some p16INK4A expression. Adenocarcinoma and in situ cases showed a combination of intense nuclear and cytoplasmic staining. It was observed that all cases of tubo-endometrioid metaplasia showed occasional nuclear positivity and definite cytoplasmic staining. These findings may have important implications for the potential utility of p16INK4A as a biomarker for glandular dysplastic lesions. While p16INK4A has been demonstrated to be an excellent marker of cervical dysplasia in squamous neoplastic lesions of the cervix, it has potential pitfalls in cervical glandular lesions that may limit the utility of this biomarker in resolving the nature of suspicious glandular lesions, particularly in cytopathology.

Atypical glandular cells?an update

The diagnostic category of atypical glandular cells (AGC) in the Bethesda system for the reporting of cervicovaginal cytology has undergone significant modification since its inception in 1988. More than a decade later, this category remains a diagnostic challenge to both clinicians and cytopathologists because of the lack of uniform cytologic criteria, the lack of interobserver agreement in the diagnosis, and the lack of standardized patient management guidelines. This article reviews the current classification of AGC in the Bethesda system, the cytomorphologic features and differential diagnosis, the clinical significance of a diagnosis of AGC, and the clinical management of patients with AGC. This article provides a comprehensive clinicopathologic review of the category of AGC.

Glandular cell atypia on Papanicolaou smears

BACKGROUND

The 2001 Bethesda System recommended qualification of atypical glandular cells (AGC) to indicate the site of origin and separated endocervical adenocarcinoma in situ (AIS) from "AGC favor neoplastic" as a specific diagnostic category. To the authors' knowledge, the literature evaluating the reproducibility of Papanicolaou (Pap) smear diagnosis of glandular cell abnormalities with emphasis on the cell of origin is limited. The aim of the current study was to investigate whether a variety of benign to neoplastic glandular lesions can be reliably classified on Pap smear with regard to diagnosis and cell of origin.

METHODS

Twenty-three conventional Pap smears (CPS) with glandular cellular changes varying from benign to adenocarcinoma (ACA) were reviewed by six observers. They were asked to categorize each smear according to cell of origin (endocervical vs. endometrial) and diagnosis (benign, AGC, or ACA). Kappa statistics were used to evaluate interobserver agreement and correlation of interobserver agreement with experience.

RESULTS

There was no consensus among observers for both the origin of the cells and the diagnosis. Interobserver agreement for site was poor (kappa < 0.4) especially in the AGC category. Unanimous agreement for site was reached for 7 of 23 smears (30%). Two of five endocervical AIS were classified as endometrial and another two were classified as benign by four observers. Interobserver agreement was poor in all diagnostic categories (kappa < 0.4) and showed slight correlation with level of experience. Unanimous agreement for diagnosis was reached for only 2 smears (9%). Three of 11 (27%) smears demonstrating preneoplastic/neoplastic processes were diagnosed as benign by 3 observers. Three (25%) benign CPS were diagnosed as ACA by 2 observers. Accurate prediction of the final histologic diagnosis by observers varied from 30% to 87% and did not correlate closely with experience.

CONCLUSIONS

Cytologic diagnosis of glandular lesions by CPS was problematic and suffered from significant interobserver subjectivity.

Atypical glandular cells

The 2001 Bethesda System has radically altered the classification of glandular abnormalities. The recognition of the cytologic features of atypical glandular cells on cervicovaginal smears is important because a significant number of patients will be found to have an underlying cancerous or dysplastic lesion of the exocervix, endocervix, or endometrium. The differential diagnosis of AGC on cytology is diverse and accurate classification is necessary because the most appropriate form of follow-up depends on the specific subcategorization of the atypical glandular cells. Because the level of interobserver agreement in the diagnosis of AGC is poor, effective communication between cytopathologists and clinicians is essential to accurately triage these patients. This article should help the cytology practitioner by providing a comprehensive review of the approach to the interpretation, clinical significance, histopathologic correlation, and management of patients who have atypical glandular cells on gynecologic cytology specimens.

Performance of ThinPrep liquid-based cervical cytology in comparison with conventionally prepared Papanicolaou smears: a quantitative survey

OBJECTIVES

The goal of this study was to evaluate the performance of ThinPrep, a liquid-based cytology preparation technique, in comparison with conventionally prepared Papanicolaou smears in detecting cervical pathology.

METHODS

Forty-seven English-language articles published between January 1990 and September 2002 were identified through Medline and manual searches. After elimination of 5 nonprimary articles, 10 unpaired studies, 5 descriptive articles with insufficient or no data, and 3 articles with data that could not be recast into a consistent format, there remained 24 usable articles. Seventeen articles contained data comparing ThinPrep with conventional cytology for 35172 patients; and 10 articles compared cytology with histology or other gold standard diagnoses for 21752 patients. Three of these articles contained both types of comparisons. The standard cytology classification into negative, atypical, low-grade (LGSIL) and high-grade (HGSIL) squamous intraepithelial lesions, and carcinoma was applied; other categorization schemes were recoded as necessary. Concordance estimates, based on five-way and dichotomous (normal/abnormal) classifications, were obtained from the 17 studies containing paired cytology data. Sensitivity and specificity rates were obtained from the 10 studies with paired cytology and histology data.

RESULTS

The two methods tend to agree in 89 and 92% of cases based on the five-level and dichotomous classifications, respectively. ThinPrep was reported as normal in 93.5% of cases of normal conventional smears. The remaining 6.5% of ThinPrep slides were classified as follows: atypical, 4.55%; LGSIL, 1.56%; HGSIL, 0.36%; invasive cancer, 0.007%. Sensitivity rates, relative to histology, were 68% (conventional) and 76% (ThinPrep), and specificity rates were 79% (conventional) and 86% (ThinPrep).

CONCLUSION

ThinPrep tends to be more sensitive and specific than conventional smears in detecting cervical dysplasia. The increased sensitivity of ThinPrep results in increased cytologic diagnosis of cervical atypia, LGSIL, HGSIL, and invasive cervical carcinoma.

ThinPrep detection of cervical and endometrial adenocarcinoma: a retrospective cohort study

BACKGROUND

The current study was performed to compare the accuracy of the ThinPrep trade mark Papanicoloau (Pap) test with that of the conventionally prepared Pap smear in detecting cervical and endometrial adenocarcinomas.

METHODS

The subject group consisted of all ThinPrep cases of atypical glandular cells of undetermined significance (AGCUS) or adenocarcinoma diagnosed between March 1998 and March 2000. Conventional smears collected between January 1996 and January 1998, before laboratory conversion to the ThinPrep system, comprised the control group. Histologic follow-up was obtained.

RESULTS

One hundred eighty-six (0.17%) of 112,058 ThinPrep Pap tests were interpreted as AGCUS/adenocarcinomas, compared with 77 (0.09%) of 83,464 conventional smears (P < 0.001). The overall sensitivity of a ThinPrep AGCUS/adenocarcinoma smear in detecting either cervical or endometrial adenocarcinoma was increased (72.0% vs. 41.5%; P < 0.001). The ThinPrep Pap test was more sensitive in detecting endometrial adenocarcinomas (65.2% vs. 38.6%; P = 0.010) and there was a trend for a higher sensitivity in detecting cervical adenocarcinomas (87.1% vs. 55.5%; P = 0.108).

CONCLUSION

The ThinPrep Pap test is a more sensitive method of detecting cervical and endometrial adenocarcinomas than the conventional Pap smear.

Cytologic features of high-grade squamous intraepithelial lesions involving endocervical glands on ThinPrep cytology

Usage of liquid-based cytology has resulted in better cellular preservation with enhancement of nuclear features. The purpose of this retrospective 2-yr study (January 1999 through December 2000) was to evaluate the cellular features of endocervical gland involvement by a high-grade squamous intraepithelial lesion (HSIL) vs. endocervical adenocarcinoma in situ (AIS) on cell samples processed by the ThinPrep method as compared to conventional smears. Of the 97 cases of CIN III diagnosed on cytology, 52 (54%) showed surface endocervical gland involvement by CIN III and form the basis of this study. There were also six cases of endocervical AIS diagnosed on histology with prior cytology. The architectural features of HSIL involving endocervical glands and AIS were similar to those previously reported on conventional smears. A consistent finding of HSIL involving endocervical glands was the loss of central cell polarity and piling within cell groups, a finding not present in AIS. Central cell polarity was maintained in cellular groupings of AIS. In addition to the cellular feature present on conventional smears, micronucleoli were clearly visualized in cells of HSIL involving endocervical glands and prominent nucleoli were present in AIS. Apoptosis and mitoses were clearly visualized in both entities. Endocervical gland involvement by HSIL has characteristic cell patterns and features on liquid-based/thin-layer cytology that permit their distinction from AIS.

Cell block preparation as an adjunctive diagnostic technique in ThinPrep monolayer preparations: a case report

The cell block preparation, which increases cellular yield by capturing any small tissue fragments in a fluid specimen, has been used to define the histologic pattern of the cells in question. This report describes a case in which processing a cell block on residual ThinPrep Pap Test material, using a thrombin-based technique, was useful in augmenting the diagnosis of a glandular lesion.

Detection of endometrial adenocarcinoma with the ThinPrep Pap test

The ThinPrep Pap Test (Cytyc Corp., Boxborough, MA) was introduced in the Loyola University Medical Center (LUMC) Cytopathology Laboratory in March 1997. This study presents a 26-month retrospective review of the cervicovaginal specimens on all patients who had a cytologic diagnosis of adenocarcinoma either by conventional (CS) or ThinPrep (TP) methods. From March 1997 through May 1999, 16,139 conventional smears and 29,589 TP Pap tests were sent to the LUMC cytopathology laboratory. The three diagnostic glandular categories included: atypical glandular cells of undetermined significance (AGUS); suspicious for adenocarcinoma, endometrial adenocarcinoma, and adenocarcinoma; not otherwise specified (nos). Cytohistologic correlation was performed on all available cases. Since endometrial adenocarcinoma occurs most frequently in peri- and postmenopausal patients, the percentage of patients over the age of 50 was determined for each method; 4,669 (29%) of the women receiving a CS were age 50 or over and 6,839 (23%) of the women who received the TP Pap test were in this age group. Sixteen endometrial lesions were identified on cytology, one (adenocarcinoma) with the CS method and 15 (six AGUS; suspicious for adenocarcinoma, four endometrial adenocarcinomas, and five adenocarcinomas; nos) with the TP method. The one CS case had biopsy confirmation. Fourteen of the 15 TP cases (93%) were confirmed by biopsy; one (7%) case had no follow-up. The TP Pap test yielded a higher percentage of endometrial adenocarcinomas (0.05%) as compared to CS (0.01%). Traditionally, CS has not been a method for the early detection of endometrial glandular lesions. However, of the patients diagnosed as having an endometrial adenocarcinoma in this study, the TP Pap test contributed to an increase in the detection of these lesions as compared to CS. The age group for the two methods was comparable.

Can glandular lesions be diagnosed in pap smear cytology?

Many reports have been published on the accuracy of the cervical vaginal smear for squamous lesions, and the literature contains fewer reports on the accuracy of the cervical vaginal smear for glandular lesions. The sensitivity of glandular lesion diagnosis depends on the subtype of lesion. The diagnostic sensitivity is highest for invasive endocervical adenocarcinoma and lowest for endometrial adenocarcinoma. The ability of some of the Bethesda system categories for glandular lesions to describe what they purport to describe is questionable. The Bethesda system categories of adenocarcinoma accurately classify adenocarcinomas. The Bethesda System category of atypical glandular cells of undetermined significance (AGUS) is a misnomer. Although many cases of adenocarcinoma in-situ are placed in this category, follow-up of patients with AGUS show that the majority of patients with clinically significant lesions have squamous dysplasias. Other categories of AGUS, such as AGUS favor endometrial origin, are more appropriately named and encompass endometrial lesions which are either neoplastic or non-neoplastic.