The cellient automated cell block system is useful in the differential diagnosis of atypical glandular cells in Papanicolaou tests

Immunocytochemistry for diagnostic cytopathology-A practical guide

Cytological specimens, which are obtained by minimally invasive methods, are an excellent source of diagnostic material. Sometimes they are the only material available for diagnosis as well as for prognostic/predictive markers. When cytomorphology is not straightforward, ancillary tests may be required for a definitive diagnosis to guide clinical management. Immunocytochemistry (ICC) is the most common and practical ancillary tool used to reach a diagnosis when cytomorphology is equivocal, to differentiate entities with overlapping morphological features, and to determine the cell lineage and the site of origin of a metastatic neoplasm. Numerous immunomarkers are available, and some are expressed in multiple neoplasms. To rule out entities within a differential diagnosis, the use of more than one marker, sometimes panels, is necessary. ICC panels for diagnostic purposes should be customised based on the clinical context and cytomorphology, and the markers should be used judiciously to preserve material for additional tests for targeted therapies in the appropriate setting. This review offers a practical guide for the use of ICC for diagnostic cytopathology, covering the most commonly encountered non-hematolymphoid diagnostic scenarios in various body sites.

Architectural aspects of cell-blocks as small biopsies

Cell-block preparations have become an essential part of integrated cytology diagnosis. They are essentially microbiopsies that are formalin fixed and embedded in paraffin. This has become more prevalent with greater sample procurement due to the advent of newer biopsy techniques and needles. Cell-blocks allow retrieval of small tissue fragments from cytology specimens that sometimes cannot be processed by alternate cytologic techniques. They represent concentrated, cell-enriched preparations that provide cytologists with the opportunity to evaluate cellular architecture, as well as to perform ancillary testing. A cell-block compatible sample may thus obviate the need for a more invasive procedure such as a tissue biopsy. Microscopic examination of cell-blocks is quick, avoids obscuring material, permits cells to be evaluated in one focal plane, and allows the histologic architecture such as glandular differentiation, papillary formations, and sometimes invasion to be easily identified. This new era of “cytohistology” accordingly requires practicing cytologists to become more familiar with histopathology. This review article discusses the benefit of various architectural patterns identifiable in cell-blocks employed as an adjunct to Pap tests, exfoliative fluid specimens, and fine-needle aspirations.

Colposcopic endocervical brushing cytology appears to be more sensitive than histologic endocervical curettage for detecting endocervical adenocarcinoma

INTRODUCTION

Colposcopic endocervical brushing cytology (CEB) is more sensitive than endocervical curettage (ECC) for detecting squamous intraepithelial lesions. There are no data on performance of CEB for detecting endocervical adenocarcinoma.

MATERIALS AND METHODS

A total of 151 patients were identified in a word search for "endocervical adenocarcinoma" in surgical pathology reports from January 2007 to June 2019. To measure sensitivity, reports of CEB or ECC samples within 1 year preceding the first surgical pathology diagnosis of at least endocervical adenocarcinoma in situ (AIS+) were examined. Specificity was measured in a cohort in which at least atypical glandular cells (AGC+) was reported in CEB or ECC.

RESULTS

Seven CEB preceding diagnosis of AIS were identified: 6 of 7 were positive or suspicious for AIS+. One of 7 was negative and it was negative on re-review. Three of 6 positive CEB cases used cell blocks with immunohistochemistry. Seventy ECC samples preceding diagnosis of AIS were identified: 40 of 70 were diagnosed as AGC+. The sensitivities of CEB and ECC for detecting AIS+ at a threshold of AGC+ are 86% and 57% (too few patients for statistics), respectively. For specificity, 12 of 18 CEB and 9 of 25 ECC reports with AGC+ were false positive by follow-up surgical pathology. The specificities of CEB and ECC are 99.4% and 99.9%, respectively.

CONCLUSION

Sensitivity of CEB for detecting AIS+ (86%) is at least as high as ECC (57%). Specificity of CEB is similar to ECC. Addition of a cell block to CEB may be useful. CEB appears to be an appropriate test for follow-up of atypical glandular cells reported on Papanicolaou tests.

Diagnostic Accuracy of Conventional Cell Blocks Along with p16INK4 and Ki67 Biomarkers as Triage Tests in Resource-poor Organized Cervical Cancer Screening Programs

Background:

Liquid based cytology with dual biomarkers has improved sensitivity and specificity in detecting high grade cervical intraepithelial neoplasia (CIN). In low resource settings, especially in organized camps, LBC is costly and immunohistochemistry on conventional pap smears is difficult to standardize with consumption of lots of reagents. In present study, to improve the accuracy of conventional pap smears and reduce the cost of biomarker testing, we evaluated conventional cell blocks (CCBs) preparations with biomarkers to detect high-grade CIN in resource-poor organized screening programs. We also studied feasibility of using CCB as primary screening test.

Material and Methods:

A total of 350 participants were included in the cross-sectional evaluation of the screening tests. A conventional Papanicolaou (Pap) smear was obtained, and another sample was then collected and placed in 10% neutral buffered formalin for CB preparation. All abnormal Pap tests and CBs were stained for the biomarkers p16INK4a and Ki67. Histopathology with p16INK4a expression was considered the gold standard. Diagnostic tests were compared using MacNemar’s test and receiver operating curves were plotted.

Results:

The sensitivity, specificity, and diagnostic accuracy of CCB cytology, CB + p16 cytology and CB + p16Ki67 cytology for detecting CIN2+ lesions were 85.71%, 100%, 97.44%; 100%, 93.75%, 94.87%; and 85.71%, 100%, 97.44%, respectively. The Ki67 index could further categorize low grade lesions into lesions with low proliferative index and with high proliferative index (Pearson chi-square p value <0.001).

Conclusion:

If CB preparation is standardized, CCB cytology with biomarkers can have better diagnostic accuracy than conventional cytology, can classify low grade lesions likely to progress and can be used in field settings as primary screening test.

Cell block preparation in urine cytology: examination of utility and workflow in an academic practice

INTRODUCTION

Urine cytology is a common non-invasive test to screen for urothelial carcinoma. Urine cell blocks may sometimes be prepared as a diagnostic aid (eg, to characterize architecture or perform immunohistochemistry). The aim of this study was to determine whether routinely preparing cell blocks on urine specimens improves diagnostic sensitivity.

MATERIALS AND METHODS

Three time periods were compared: time period 1 (prior to November 2009; 1437 consecutive selected cases), when cell blocks were rarely prepared; period 2 (November 2009 to May 2010; 1230 selected cases), when cell blocks were prepared on all cases; and period 3 (after May 2010; 1499 consecutive selected cases), when cell blocks were made only when indicated (for samples with substantial cellular pellets or when requested by a pathologist).

RESULTS

Patient demographics and the type of specimens received were relatively similar during the 3 time periods. Increased preparation of cell blocks was not accompanied by a notable improvement in specimen adequacy rate, given that <1%, 2%, and 1% of samples were unsatisfactory for the 3 periods. Only the proportion of atypical cases differed during the time periods, being highest in period 1 (23%), but lower in periods 2 and 3. Turnaround time was fastest for period 1 (mean: 47 hours, median: 33 hours), and slower for period 2 and period 3.

CONCLUSION

These data show that routinely preparing cell blocks for urine samples did not improve our laboratory's specimen adequacy rate. Nonetheless, cell block preparation on urine samples did help lower the proportion of atypical diagnoses, when routinely or selectively prepared. Because preparation of cell blocks on all urine cases can be costly and only provides minimal added clinical benefit, our recommendation is to rather judiciously utilize cell blocks when screening urine cytology samples.

Cell Block in Cytological Diagnostics: Review of Preparatory Techniques

OBJECTIVE

The cell block (CB) technique refers to the processing of sediments, blood clots, or grossly visible tissue fragments from cytological specimens into paraffin blocks that can be cut and stained by the same methods used for histopathology. The technique brings additional tissue architectural information. CB can be used for ancillary techniques such as immunocytochemistry and molecular techniques.

STUDY DESIGN

We reviewed the literature on the various preparatory techniques of CBs.

RESULTS

There is a wide range of preparatory techniques for CBs and no golden standard for CBs exists: tens of methods are used in various institutions. The majority of the methods are modified in house techniques with a few commercially available kits. The techniques most commonly used are the plasma/thrombin method, the agar method, and commercially available Histogel- and Cellient CB-methods. Dissatisfaction with the cellular yield of the CBs is common.

CONCLUSIONS

In the CBs, the cytological material is preserved for future use, which is a tremendous advantage in the era of targeted therapy and biobanking. The CB is thus central to the future of cytology: more can be done with less material and with less invasiveness to the patient.

Cytologic parameters predicting neoplasia in Papanicolaou smears with atypical glandular cells and histologic follow-up: a single-institution experience

INTRODUCTION

Studies investigating histologic follow-up of The 2001 Bethesda System diagnosis of atypical glandular cells (AGC) have focused on various screening methods, patient populations, and Papanicolaou preparations. Our aim was to report the histologic follow-up of AGC diagnoses from ThinPrep slides and evaluate specific cytologic features predicting benign or malignant follow-up results.

MATERIALS AND METHODS

A retrospective search identified liquid-based cervical cytology results interpreted as AGC. AGC diagnoses were stratified into four groups: atypical endometrial cells (AGC-EM); atypical endocervical cells (AGC-EC); AGC, favor neoplastic (AGC-FN); and AGC not otherwise specified (AGC-NOS). Evidence of disease was based on histologic follow-up (biopsy or resection specimen) with a diagnosis of cancer, complex endometrial hyperplasia, or high-grade squamous dysplasia. Available slides were blindly reviewed for specific cytologic features. Statistical analysis compared cytologic factors that would predict benign or malignant follow-up.

RESULTS

We interpreted 264 samples as AGC from 2005 through 2009. Of the 246 (93.2%) with follow-up histologic material, 60 (24.4%) were AGC-EM; 36 (14.6%) were AGC-EC; 28 (11.4%) were AGC-FN; and 122 (49.6%) were AGC-NOS. Neoplasia was diagnosed in 80 (32.5%). Neoplastic cases showed significantly increased numbers of single cells, cells in 3-dimensional clusters, engulfed neutrophils, nuclear enlargement, increased nuclear-to-cytoplasmic ratio, irregular nuclear borders, reniform nuclei, loss of polarity, and macronucleoli.

CONCLUSIONS

Cytologic parameters can be used to predict benign from neoplastic glandular lesions. Biopsy follow-up is necessary to correlate cytologic findings when AGC is diagnosed on a Papanicolaou smear.

The utility of pap cell block preparations with liqui-PREP™ cell pellets to clarify the cytological diagnosis of atypical squamous cells of undetermined significance and atypical glandular cells

OBJECTIVE

Atypical squamous cells of undetermined significance (ASCUS) and atypical glandular cells (AGC) reflect cellular abnormalities insufficient for clear diagnosis. We used cell pellets obtained from liquid-based cytology (LBC) to prepare cell blocks (CB) and clarify the initial diagnosis of ASCUS and AGC.

STUDY DESIGN

A total of 393 CBs with initial diagnosis of ASCUS or AGC were processed. Of those, 305 of the ASCUS and 20 of the AGC had adequate specimens. We compared results of CBs prepared from ASCUS and AGC to determine which had higher frequencies of higher-grade lesions.

RESULTS

A majority of specimens (83%) were adequate for evaluation. Compared with the initial diagnosis, 14% (42/305) of ASCUS were diagnosed with low-grade squamous intraepithelial lesion (LSIL) in CB, while 10% (2/20) of AGC were diagnosed with LSIL or adenocarcinoma. No statistical relationship between the initial diagnosis of ASCUS and AGC and results of higher-grade lesions in CB is evident as determined by p value greater than 0.05 (p = 0.228).

CONCLUSIONS

CBs prepared from Liqui-PREP cell pellets are, in most cases, assessable and can be useful as an adjunctive test to help clarify the initial diagnosis of ASCUS and AGC. Diagn. Cytopathol. 2017;45:520-525. © 2017 Wiley Periodicals, Inc.

Expression and utility of IMP3 in the differential diagnosis of atypical glandular cells and adenocarcinoma in liquid-based cervical cytology

BACKGROUND

Atypical glandular cell (AGC) interpretation in gynecological cytopathology presents many diagnostic challenges. We evaluated the expression of IMP3 in liquid-based cervical cytology and its utility in differentiating premalignant/malignant glandular lesions from benign/reactive processes. Additionally, we tried to determine whether IMP3 may be useful in differentiating among the types of uterine adenocarcinomas.

DESIGN

Our cohort included 82 cases; 59 diagnosed with AGC and 23 with adenocarcinoma (Ac). IMP3 immunocytochemical stain was performed on ThinPrep slides and the results correlated with subsequent biopsy findings. IMP3 positivity was assessed by strong (2+ and 3+) granular cytoplasmic staining in at least one group of three epithelial cells.

RESULTS

In the AGC group, IMP3 was positive in 14 (73.7%) of 19 cases that on histologic follow-up were confirmed Ac, and 39 (98.6%) of 40 non-glandular lesions/benign cases were negative. In the Ac group, IMP3 was expressed in 16 (69.6%) of 23 cases, of which 16 (72.2%) of 21 were uterine Ac. By combining the two groups, and excluding the 2 extrauterine carcinomas, IMP3 was positive in 30 (75%) of 40 uterine Ac, most of which (86.7%) were in situ/invasive endocervical Ac, and type II endometrial Ac (Papillary Serous and Clear Cell Carcinoma), and only 40% endometrioid Ac.

CONCLUSION

In ThinPrep slides with AGC, IMP3 positivity predicts the presence of a significant endocervical or endometrial lesion on subsequent histology, and may also be a potential diagnostic tool useful in differentiating among the types of adenocarcinomas of the female lower genital tract.

Cell blocks in cytopathology: a review of preparative methods, utility in diagnosis and role in ancillary studies

The cell block (CB) is a routine procedure in cytopathology that has gained importance because of its pivotal role in diagnosis and ancillary studies. There is no precise review in the published literature that deals with the various methods of preparation of CB, its utility in diagnosis, immunocytochemistry (ICC) or molecular testing, and its drawbacks. An extensive literature search on CB in cytology using internet search engines was performed for this review employing the following keywords: cell block, cytoblock, cytology, cytopathology, methods, preparation, fixatives, diagnostic yield, ancillary and molecular studies. Ever since its introduction more than a century ago, the CB technique has undergone numerous modifications to improve the quality of the procedure; however, the overall principle remains the same in each method. CBs can be prepared from virtually all varieties of cytological samples. In today's era of personalized medicine, cytological specimens, including CBs, augment the utility of cytological samples in analysing the molecular alterations as effectively as surgical biopsies or resection specimens. With the availability of molecular targeted therapy for many cancers, a large number of recent studies have used cytological material or CBs for molecular characterization. The various techniques of CB preparation with different fixatives, their advantages and limitations, and issues of diagnostic yield are discussed in this review.