Cell block preparation on residual ThinPrep sample

Comparison of liquid-based cytology and cell blocks prepared from cell remnants for diagnosis of cervical pathology

BACKGROUND

Cervical cancer is a global public health problem with high mortality. Advances in screening programs for cervical cancer are considered key to eliminate cervical cancer. We aimed to examine the contribution of cell block analysis to the detection of epithelial cell abnormalities in cervical smear samples.

METHODS

A total of 559 patients with suspected cervical pathology were examined, and their samples were analyzed by both liquid-based cytology (LBC) and cell blocks. The biopsy results of 149 out of the 559 patients were obtained.

RESULTS

Of the 50 patients who were identified as HSIL by biopsy, only 12 were diagnosed as HSIL by the LBC method, 22 as LSIL, 12 as ASCUS, and 4 as ASC-H (p < 0.001). With the cell block analysis, results for these patients were: 20 HSIL, 17 LSIL, 7 NILM, 4 'unsatisfactory', and 2 ASC cases (p < 0.001). LBC detected only 1 of the 10 patients with biopsy-diagnosed tumors, while 7 of these were defined as HSIL, 1 as ASCUS and 1 as AGC. The results of cell block analysis in patients with biopsy-diagnosed tumors were as follows: 7 HSIL, 1 tumor, 1 ASC and 1 LSIL.

CONCLUSIONS

Cell block analysis might be superior to LBC in terms of diagnostic accuracy in cervical pathologies, particularly in the detection of HSIL. However, both methods were similarly poor in diagnosing tumors. Cell blocks may improve diagnostic accuracy and can be a complementary method to LBC, while having the advantage of revealing histological architecture.

Heat Induced Processing of Cellblocks with Significant Reduction in Overall Turn Around Time

Introduction

Cellblock (CB) with immunohistochemistry (IHC) is practically indispensable in the diagnostic workup of serous effusions; however, CB requires a minimum of 15-20 h for routine histopathological processing. A reduction in processing time can expedite a faster diagnosis.

Aim

This study was undertaken to evaluate the utility of the heat-induced CB (HICB) technique.

Material and Methods

Two sets of agar-embedded CBs were processed from 50 effusion samples. CBs were further processed by conventional and rapid methods. Conventional CBs (CCB) were processed in a histoprocessor, whereas rapid CB was processed in a heated water bath with an agitation facility. For HICB processing, dehydration and clearing were performed at 50°C followed by paraffin wax impregnation at 65°C temperature. From both CBs, sections of 5 um thickness were cut and stained with hematoxylin and eosin (H and E). Cell morphology, cost, and time were compared between the two methods. The feasibility of IHC was attempted in a few cases.

Results

HICB was completed within 4.30 h compared with CCB. Diagnoses on both CBs were concordant in all the cases. Incomplete dehydration was noted in six (12%) cases, but the diagnosis was not compromised. No additional cost was involved in HICB. On IHC, both HICB and CCB exhibited equivalent expression.

Conclusions

HICB is a rapid, innovative, simple, and cost-effective technique and expedites faster diagnosis. It does not require any advanced equipment.

Culture Cell Block Controls as a Tool to the Biomolecular Diagnosis of Infectious Diseases

The cell block (CB) technique has allowed easy obtainment of samples such as cellular and culture suspensions, to perform specific molecular tests such as immunohistochemistry and in situ hybridization. It has been improved along time, accuracy, and quality of the diagnoses, however, the cost of a commercial gel matrix for the preparation of CB is high and not suitable depending on the situation. The objective of this study is to test agarose as an alternative to the commercial gel matrix in the preparation of Aspergillus fumigatus' CB.

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.

Performance of the Cellslide® automated liquid-based cytology system amongst HIV-positive women

Background

Many women undergoing cervical screening as part of a national South African screening programme may be positive for HIV. The performance of liquid-based cytology (LBC) on samples from HIV-positive women needs to be determined.

Objectives

The performance of the Cellslide^® automated LBC system was evaluated as a possible alternative to conventional cytology in a national cervical cancer screening programme.

Methods

Split samples from 348 HIV-positive women attending an HIV treatment clinic in Johannesburg, South Africa were examined by conventional cytology and monolayer LBC methods. All samples were stained, examined and reported in the same manner. Cytotechnologists were blinded to the conventional smear diagnosis if the LBC smear was screened and vice versa.

Results

The same percentage of inadequate smears (1.4%) was obtained by conventional cytology and LBC. Atypical squamous cells of undetermined significance were observed in 5.2% of conventional smears and 4.0% of LBC smears. Low-grade squamous intraepithelial lesions were found in 35.6% of conventional smears and 32.7% of LBC smears. Only one conventional smear was categorised as atypical squamous cells – cannot exclude a high-grade lesion, whereas five such cases were identified on LBC. High-grade squamous intraepithelial lesions were seen in 21.6% of conventional smears and 23.3% LBC smears. No invasive carcinoma was identified.

Conclusion

The performance of the Cellslide^® LBC system was similar to that of conventional cytology in this population of high-risk HIV-positive women, indicating that it may be introduced successfully as part of a cervical cancer screening programme.

Whole-Slide Imaging of Pap Cellblock Preparations Is a Potentially Valid Screening Method

OBJECTIVE

To date, the impact of digital imaging on routine cytology remains far from perfect. Cellblock (CB) preparations from Pap samples have been shown to be diagnostically valuable. We evaluated the validity of utilizing whole-slide imaging (WSI) prepared from Pap CBs as a screening tool.

STUDY DESIGN

A total of 1,110 CB slides prepared from residual Pap samples were analyzed - 563 normal, 282 atypical squamous cells of undetermined significance (ASCUS), 12 atypical squamous cells-cannot exclude high-grade squamous intraepithelial lesion, 188 low-grade squamous intraepithelial lesions (LSIL), 36 high-grade squamous intraepithelial lesions (HSIL), 25 atypical glandular cells of undetermined significance, 1 adenocarcinoma in situ, 2 invasive adenocarcinomas, and 1 squamous cell carcinoma. Virtual slides were obtained using the Aperio system. Test performance characteristics of liquid-based samples and WSI from CB samples were compared.

RESULTS

Average sensitivity and specificity of the five WSI reviewers was 58.3 and 85.1% for ASCUS, respectively, 54.1 and 93.9% for LSIL, and 51.8 and 98.8% for HSIL. Overall WSI sensitivity and specificity for detecting lesions was 82.1 and 86.2%, respectively. Agreement (kappa values) between WSI reviewers was 0.56 for ASCUS, 0.69 for LSIL, 0.67 for HSIL, and 0.74 for negative samples.

CONCLUSIONS

WSI of CB preparations is a feasible method to achieve high-quality specimen preparations. It is as sensitive as liquid-based methods and appears to be highly specific for the detection of LSIL and HSIL.

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.

Whole Slide Imaging of Pap Cell Block Preparations versus Liquid-Based Thin-Layer Cervical Cytology: A Comparative Study Evaluating the Detection of Organisms and Nonneoplastic Findings

OBJECTIVE

Cervical cancer is one of the most common malignancies worldwide, yet it is preventable by population screening. In a previous study, we confirmed the feasibility of utilizing whole slide imaging (WSI) of cell block (CB) preparations to overcome the limitations of digitizing cytologic samples. In this study, we evaluated the accuracy of WSI in identifying various organisms and nonneoplastic findings.

STUDY DESIGN

A total of 335 WS images from Pap CB preparations were analyzed using the Aperio system. The test performance characteristics of ThinPrep (TP) and WSI samples were compared for adequacy, for the presence of bacterial vaginosis (BV), fungi, Trichomonas vaginalis (TV) and herpes simplex virus (HSV) and for nonneoplastic findings.

RESULTS

The WSI samples contained optimal material from all preparations. BV was diagnosed in 33 WSI versus 36 TP samples. Budding yeasts and/or pseudohyphal forms were noted in 18 WSI versus 19 TP samples. TV organisms (10 of 11 samples) and 1 HSV case were accurately identified in the WSI and TP samples. Squamous metaplasia, keratosis and reactive/reparative and inflammatory changes were easily identified by WSI.

CONCLUSIONS

The concept of WSI from Pap CB preparations is potentially feasible for adoption. Digital remote web-based technology eliminates the need for an individual on site, saving time and resources.

Diagnostic value of p16INK4A, Ki-67, and human papillomavirus L1 capsid protein immunochemical staining on cell blocks from residual liquid-based gynecologic cytology specimens

BACKGROUND

This study was conducted to evaluate the reliability and role of cell block preparations in the diagnosis of neoplastic and preneoplastic lesions of the cervix and to improve the value of cell block preparations in diagnosing and predicting the prognosis of cervical lesions through immunostaining of p16INK4A (p16), Ki-67, and human papillomavirus (HPV) L1 capsid protein (HPV L1).

METHODS

In total, 138 specimens were diagnosed on liquid-based cytology (LBC) and cell block preparations, and 63 specimens were subjected subsequently to tissue follow-up and immunostaining for p16, Ki-67, and HPV L1 on cell block sections.

RESULTS

In 42 specimens that were diagnosed as low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion (HSIL), and squamous cell carcinoma (SCC) on cell blocks, 38 specimens (90.5%) were confirmed by histopathologic reports, and there was slightly better than 81.6% agreement between LBC and tissue follow-up. Immunointensity and cells that were positive for p16 were enhanced according to increased pathologic grade and differed statistically between cervical intraepithelial neoplasia 1 (CIN-1) and CIN-2/CIN-3 as well as SCC. The positive rates of HPV L1 decreased gradually according to the severity of cervical neoplasia, and HPV L1/p16 expression patterns were related to the severity of cervical lesions.

CONCLUSIONS

The cell block preparation technique was complementary to LBC, and the authors concluded that the application of LBC combined with cell block preparations may improve the diagnostic accuracy of cytology. Immunostaining for p16 and Ki-67 on cell block preparations can help to improve the diagnostic accuracy of HSIL and SCC. A combined expression pattern of p16 and HPV L1 may serve as a valuable index for predicting prognosis and follow-up of cervical dysplastic lesions.

The diagnostic utility of cell blocks prepared from residual SurePath Pap material for detection of human papilloma virus

This study was undertaken to determine if tissue sections from cell block prepared from the residual cellular sediment of Pap test vials could be used for immunohistochemistry (IHC) or in situ hybridization (ISH) for the detection of human papilloma virus (HPV) and to determine if these stains could clarify the nature of atypical cases in certain cases. Cases included in this retrospective study are categorized into 3 groups. Group 1 included 12 positive and 10 negative cases that were used to optimize the IHC and ISH staining protocol for the detection of HPV. Cases selected in group 2 were included to validate and verify the IHC and ISH stains. We validated 20 negative and 37 positive cases. Group 3 included 37 atypical cases. Unused material from the corresponding liquid-based (SurePath) Pap test specimens were retrieved and used to prepare paraffin-embedded cell blocks. Hematoxylin and eosin-stained cell-block sections were evaluated for abnormal cells. The IHC and ISH stain protocols for detection of HPV DNA were successfully optimized, validated, and verified. The sensitivity for the detection of HPV DNA using IHC in atypical squamous cells of undetermined significance was 80% and in atypical squamous cell, cannot rule out high grade, was 78% whereas the specificity was 100% in both lesions. Both the sensitivity and specificity for the detection of HPV DNA using the ISH were 100%. This study demonstrated that cell-block sections prepared from residual SurePath Pap test material could be used for detection of HPV DNA by both IHC and ISH and clarify the nature of atypical cells on cell-block sections.

High-risk human papillomavirus DNA test results are useful for disease risk stratification in women with unsatisfactory liquid-based cytology pap test results

OBJECTIVES

This study assesses whether high-risk human papillomavirus (HPV) DNA test results from residual vial fluid of unsatisfactory liquid-based cytology(LBC) samples might provide useful information on disease risk.

MATERIALS AND METHODS

Patients with unsatisfactory imaged ThinPrep Pap test results and available Hybrid Capture 2 high-risk HPV results were identified at an academic women's hospital laboratory between July 1, 2005, and July 31, 2007. Follow-up repeat cytology results, HPV results, and available biopsy results were analyzed.

RESULTS

Three hundred four patients with unsatisfactory cytology results and HPV test results were studied. Eleven (3.6%) of 304 tested positive for HPV DNA, and 293 tested HPV negative. Five (45%) of 11 HPV-positive patients had detectible low-grade squamous intraepithelial/cervical intraepithelial neoplasia 1 during a mean follow-up period of almost 6 months. Among 293 women with negative HPV results, only 1 case of cervical intraepithelial neoplasia 1 was identified during roughly the same follow-up period.

CONCLUSIONS

A positive high-risk HPV result associated with an unsatisfactory ThinPrep Pap test result identified patients at risk for diagnosis of an undetected squamous intraepithelial/cervical intraepithelial neoplasia. Negative high-risk HPV results associated with an unsatisfactory LBC had high negative predictive value in this limited study. The overall low detection rate for significant disease on follow-up of all patients with unsatisfactory imaged LBC is similar to findings reported in another LBC study but differs from studies reporting increased risk for undetected disease in women screened with unsatisfactory conventional Pap smears.

Comparison of cell block preparation methods for nongynecologic ThinPrep specimens

The purpose of this study was to compare four cell block (CB) methods in the setting of nongynecologic ThinPrep (TP) specimens. 48 CBs were prepared from 12 nongynecologic TP specimens using the following CB methods: (1) Inverted filter sedimentation (IFS); (2) Thrombin method; (3) Albumin method; (4) Simple sedimentation. Each CB was assigned a cellularity score: 0 no cells, 1+ hypocellular, 2+ hypocellular with tissue fragments, 3+ cellular. A score of 2+ or 3+ was given for 11/12 of thrombin, 7/12 IFS, 5/12 albumin, and 2/12 simple sedimentation CBs. Thrombin CBs demonstrated a pale background clot with evenly distributed cells. Albumin CBs had a cracked uneven background. IFS CBs had a clear background, but were technically difficult and cells appeared artifactually crowded. In the setting of nongynecologic TP specimens, the thrombin CB was easily prepared and produced the best CB in regards to cellularity, cell distribution, and background quality.

Immunohistochemical detection of p16INK4a in liquid-based cytology specimens on cell block sections

BACKGROUND

Colposcopy biopsy procedure is a standard recommendation for atypical squamous cell cannot exclude high-grade lesion (ASC-H) in abnormal Papanicolaou smears. p16 (p16INK4a), a cell cycle regulator, has been shown to be overexpressed in squamous dysplasia. To further improve the diagnostic accuracy of the ASC-H Papanicolaou smear and to reduce unnecessary procedures, the authors evaluated the utility of immunodetection of p16 in liquid-based cytology specimens on cell blocks.

METHODS

Seventy-five liquid-based (SurePath; TriPath Imaging, Inc. Burlington, NC) cytology specimens were prepared for cell blocks. Three groups (G1, G2, and G3) of cases were included: G1 comprised 44 cases of ASC-H; G2, 14 cases of high-grade dysplasia; and G3, 17 negative/reactive cases. All cases in G1 were confirmed by cervical biopsy or Digene Hybrid Capture 2 (Digene, Gaithersburg, Md) human papilloma virus (HPV) testing. Immunodetection for p16 was performed on cell blocks.

RESULTS

In G1, 26 of 44 (59%) cases showed squamous dysplasia, with 14 high-grade squamous intraepithelial lesion (HSIL) cases. Twenty-two of 28 (79%) p16-positive cases were confirmed by surgical biopsy or HPV testing, with a diagnostic sensitivity of 85%, specificity of 67%, positive predictive value (PPV) of 79%, and negative predictive value (NPV) of 75%. Four cases with false-negative staining for p16 were identified. All 28 cases of HSIL (14 from G1 and 14 from G2) were positive for p16.

CONCLUSIONS

1) p16 is a sensitive marker to confirm the diagnosis of ASC-H on a cell block; 2) Multiple unstained slides with adequate cellularity can be obtained from each cell block; and 3) Additional markers can be used to further increase diagnostic sensitivity and specificity.

Non-gynecologic cytology on liquid-based preparations: A morphologic review of facts and artifacts

Liquid-based preparations (LBP) are increasingly being used both for gynecologic (gyn) and non-gynecologic (non-gyn) cytology including fine needle aspirations (FNA). The two FDA-approved LBP currently in use include ThinPrep (TP), (Cytyc Corp, Marlborough, MA) and SurePath (SP), (TriPath Imaging Inc., Burlington, NC). TP was approved for cervico-vaginal (Pap test) cytology in 1996 and SP in 1999 and both have since also been used for non-gyn cytology. In the LBP, instead of being smeared, cells are rinsed into a liquid preservative collection medium and processed on automated devices. Even after a decade of use, the morphological interpretation of LBP remains a diagnostic challenge because of somewhat altered morphology and artifacts or facts resulting from the fixation and processing techniques. These changes include cleaner background with altered or reduced background and extracellular elements; architectural changes such as smaller cell clusters and sheets, breakage of papillae; altered cell distribution with more dyscohesion and changes in cellular morphology with enhanced nuclear features, smaller cell size and slightly more three-dimensional (3-D) clusters. Herein, we review the published literature on morphological aspects of LBP for non-gyn cytology.

The utility of p16INK4a and Ki-67 staining on cell blocks prepared from residual thin-layer cervicovaginal material

BACKGROUND

Cell blocks can be prepared from residual thin-layer cervicovaginal (ThinPrep) material and can be used in immunohistochemical staining assays for p16INK4a and Ki-67, which are surrogate markers related to human papillomavirus infection and cell proliferation, respectively. The objectives of the current study were 1) to investigate the feasibility and the role of cell block preparations in identifying significant neoplastic and preneoplastic lesions of the uterine cervix and 2) to assess the feasibility of using p16INK4a and Ki-67 immunohistochemical staining patterns on cell blocks to identify significant preneoplastic cervical lesions.

METHODS

Cervicovaginal cytology specimens from 85 patients were analyzed. Cytologic diagnoses based on ThinPrep Papanicolaou test results were as follows: squamous cell carcinoma was diagnosed in 3 specimens, high-grade squamous intraepithelial lesions (HSIL) were diagnosed in 27 specimens, low-grade squamous intraepithelial lesions (LSIL) were diagnosed in 20 specimens, and atypical squamous cells of uncertain significance (ASCUS) were diagnosed in 11 specimens. Diagnoses of negativity for intraepithelial lesions or malignancy (NILM) were made in 24 specimens. Cell block sections were stained with hematoxylin and eosin and were immunostained with antibodies against p16INK4a protein and Ki-67 antigen.

RESULTS

The cytomorphologic diagnoses made using cell block preparations were as follows: SCC in 2 specimens, HSIL in 20 specimens, LSIL in 30 specimens, NILM in 32 specimens, and no diagnosis in 1 specimen. In 62 cases (73%), the diagnoses made using cell block preparations were in agreement with the ThinPrep diagnoses. Immunostaining of cell blocks for p16INK4a and Ki-67 exhibited a statistically significant association (P < 0.05) with the presence of significant lesions on either cell block or ThinPrep analysis.

CONCLUSIONS

To the authors' knowledge, p16INK4a has not been analyzed previously in ThinPrep cell blocks, and the correlation between Ki-67 expression and cell block diagnoses also has not been reported previously. The current results indicate that cell blocks prepared from residual ThinPrep material represent an additional reliable diagnostic tool in the evaluation of cervical samples. Furthermore, immunohistochemical studies may be helpful in differentiating significant preneoplastic changes from other cervical lesions, such as atrophy.

Cell block findings from residual PreservCyt samples in unsatisfactory ThinPrep Paps: no additional benefit

Our objective was to determine whether cell blocks (CB) performed on unsatisfactory ThinPrep Pap Test residual samples rendered additional clinically significant pathologic findings not detected in the original ThinPrep Pap smears. One hundred consecutive ThinPrep Paps categorized as unsatisfactory were selected for this study. The cytologic diagnosis of unsatisfactory was based on lack of cellularity (squamous) or complete obscuring blood or inflammation. Residual PreservCyt samples from these consecutive unsatisfactory ThinPrepPaps were used to prepare a cell block, using the inverted filter technique. One hematoxylin-eosin (H&E)-stained slide was prepared and evaluated. The amount and the cellular changes were noted for all smear constituents and compared with the original slides. The average patient age was 32 +/- 11 yr. The ThinPrepPap was performed as a follow-up on a previous abnormal smear (12%), pregnancy (25%), abnormal bleeding (22%), or previous unsatisfactory ThinPrepPap (5%), or as routine screening (36%). Variable amounts of endocervical cells, endometrial cells, and metaplastic cells, as well as a variable number of squamous epithelial cells, were present in 89%, 9%, 50%, and 35% in the CB method vs. ThinPrep, respectively. Abnormal cellular changes were noted in 15% of patients (9% with LSIL, and 6% with atypia of undetermined significance); 9 patients with squamous dysplasia had a previous abnormal ThinPrep Pap. A follow-up Pap smear and/or cervical biopsy were performed in 10 of the 15 patients with abnormal cytology detected on CB method revealing: LSIL (1 patient), HSIL (1 patient), ASCUS (1 patient), and within normal limits (7 patients). The findings indicate that the preparation of a CB does not contribute significantly. Importantly, no carcinomas or HSILs were identified on CB preparations. Since a large majority of lesions identified were LSILs, a repeat Pap smear in these cases represented a more cost-effective strategy than cell block preparation, although a cell block preparation may be useful in selected cases.

Diagnostic value, feasibility, and validity of preparing cell blocks from fluid-based gynecologic cytology specimens

BACKGROUND

The current study was conducted to investigate the diagnostic value, feasibility, and validity of preparing cell blocks from fluid-based gynecologic cytology methods.

METHODS

The authors independently reviewed 125 cell blocks prepared from material remaining after the ThinPrep smear was diagnosed, with a concentration on those cases demonstrating abnormal results.

RESULTS

The majority of cases were easy to diagnose on hematoxylin and eosin stained sections. The addition of a cell block preparation increased the detection of an endocervical cell component compared with the use of ThinPrep alone. Of the 125 cell blocks studied, 15 were interpreted as high-grade squamous intraepithelial lesions, 70 were interpreted as low-grade SILs, 24 were interpreted as atypical squamous cells of undetermined significance, and 16 were determined to be within normal limits. Eighty-six of the cell blocks (69%) were found to be in agreement with the ThinPrep diagnosis, 29 (23%) demonstrated a lesser degree of abnormality on the cell block compared with the ThinPrep slide, and 10 (8%) demonstrated changes that were more severe than those diagnosed on the corresponding ThinPrep slide. Of the 54 cases for which histopathologic follow-up was available (e.g., punch biopsy, cone biopsy, or hysterectomy), the biopsies, cytologies, and cell blocks were concordant in 15 cases (28%). Biopsy results were found to agree more closely with the cell block preparation than the ThinPrep slide in eight cases, and were found to identify more closely with the ThinPrep slide in four cases. Biopsy showed changes that were less severe than those found on either cytology or cell block in 23 cases (43%). Biopsy demonstrated changes that were more severe than those observed on either cytology or cell block in 4 cases (7%).

CONCLUSIONS

The results of the current study demonstrate that this technique is feasible and useful as a complement to routine gynecologic cytology slide preparation and examination.

Specialized preparative devices are not needed for liquid-based, thin-layer cytology: an alternate manual method using a metastable alcoholic gel

The blending and use of a metastable alcoholic gel is described. The gel creates durable, uniform suspensions of cells and small aggregates of cells. It allows the random, uniform transfer of virtually any liquid-fixed cytology specimens to a glass slide without the use of specialized devices, proprietary disposables, or adhesive-coated glass slides. The method is inexpensive and can be performed in a timely fashion, not impacting laboratory turnaround times or requiring the specimen to be processed by other laboratories. It empowers cytology laboratories of any size or level of complexity to make slides from readily available commercial cytology fixatives. It allows the total contents of liquid-based cytology specimen vials to be examined, providing a "cytological method" for quality assuring liquid-based cytology samples.

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.