Thin-layer cervical sample evaluation: Conventional light microscopy versus digital whole-slide imaging.

Whole-slide imaging (WSI) has been adopted in many fields of pathology for education, quality assurance, and remote diagnostics. In 2021, the College of American Pathologists (CAP) updated guidelines to support pathology laboratories regarding the WSI systems validation process. However, the majority of published literature refers to histopathology rather than cytology. The aim of this study was to compare conventional light microscopy (CLM) and WSI in thin-layer cervical samples evaluation according to CAP guideline. A sample set of 64 thin-layer cervical specimens from women 25-64 years old who participated in cervical cancer screening programs in Tuscany was distributed among five cytologists at Institute for Cancer Research, Prevention and Clinical Network (Florence, Italy) for CLM analysis. After 2 weeks, the corresponding 64 digitally scanned slides were available at several magnifications for WSI evaluation. Substantial/near perfect agreement between CLM and WSI evaluation (0.77 ≥ κ ≥1) was observed for the negative for intraepithelial lesion or malignancy (NILM) class with concordance rates from 83.3% to 100%.Variability in concordance was observed among all the cytologists: 50%-85.7% for low-grade squamous intraepithelial lesion (LSIL), 47.1%-100% for high-grade squamous intraepithelial lesion (HSIL), 50%-100% for atypical glandular cells (AGCs) favors adenocarcinoma (ADK) with moderate/near perfect agreement (0.47 ≥ κ ≥1). Concordance and agreement rates were also variable within the "borderline" cytological categories of atypical squamous cells of undetermined significance (ASC-US), atypical squamous cells cannot exclude an HSIL (ASC-H), and AGCs with lower or not computable kappa for some readers. The overall intralaboratory concordance between CLM and WSI was 92.9% with a near perfect agreement (κ = 0.84) for NILM. Substantial agreement (κ ≥0.65) was assessed for LSIL, HSIL/squamous cell carcinoma, AGCs, and ADK categories whereas the agreement was lower (κ ≤0.39) for ASC-US and ASC-H. This study showed an overall substantial/near perfect agreement between CLM and WSI for all the cytological categories except the "borderline" ASC-US and ASC-H. Further progress in cytology WSI systems are needed before introducing it in routine diagnostics.

Viti J ，Di Stefano C ，Giunti S ，Pompeo G ，Pezzati P ，Terreni A ，Sani C ，Cytology Working Group ... -  《-》

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

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. 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. 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. 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.

Tawfik O ，Davis M ，Dillon S ，Tawfik L ，Diaz FJ ，Amin K ，Fan F ... -  《ACTA CYTOLOGICA》

Analysis of the Differences between Bethesda Groups according to Conventional Smear and Liquid-Based Cytology Methods in Cervicovaginal Cytology: A Single-Center Experience with 165,915 Cases.

Liquid-based cytology (LBC) has replaced conventional smear (CS) in the world. In this study, through a series with a large number of cases, we aimed to make a comparison and general evaluation in all groups, primarily epithelial abnormalities, according to LBC and CS methods. This study was carried out in a private pathology laboratory located in a metropolitan city, where cytological materials sent from many clinics were examined. There were 165,915 cases whose smears were examined between 2012 and 2020, most of them conventional (131,224 CS, 34,691 LBC). Cases were evaluated on the basis of the Bethesda 2014 classification and divided into sub-diagnostic categories after they were divided into two main groups as "with epithelial abnormalities" and "without." χ2 and Fischer's precision statistical tests were conducted using SPSS 23.0 package. In the CS process, cervical samples were obtained using an endocervical brush and a spatula. Cells were directly spread onto the slides and promptly fixed in 95% ethanol, followed by staining with the standard Papanicolaou stain. For LBC ThinPrep, cervical specimens were gathered using a cervix brush. The brush was washed in a vial and discarded. Finally, cells were isolated through vacuum filtration and transferred to the slide using air pressure. Squamous cell abnormalities (atypical squamous cells of undetermined significance [ASC-US], atypical squamous cells - cannot exclude high-grade squamous intraepithelial lesion [ASC-H], low-grade squamous intraepithelial lesion [LSIL], high-grade squamous intraepithelial lesion [HSIL], squamous cell carcinoma, atypical glandular cells of undetermined significance) were reported in 5,696 (3.43%) cases. ASC (ASC-US + ASC-H)/SIL ratio (1.36/2.04) was found to be 0.67 (recommended Bethesda ratio is <3). ASC-US (p < 0.001), ASC-H (p < 0.001), and HSIL(p < 0.001) detection rate of LBC was found to be significantly higher than CS. ASC-US (1.8/1.2), ASC-H (0.08/0.008), and HSIL (0.6/0.3) case ratios of LBC/CS were found to be significantly higher in LBC. LSIL (1.72/1.66) rate was similar. LBC is superior to CS in detecting epithelial lesions. In addition to being used as a screening method, it is clear that it makes a great contribution to reducing cervical carcinomas due to HPV typing. Definitive comments regarding comparison of methods on reactive changes and microorganism detection are challenging. Preanalytical factors might account for these situations.

Ucak R ，Dilbaz OF ，Polat N 《-》

Diagnostic Agreement in Whole Slide Digital Images of Cervical Cytology and Cell Blocks.

Cell blocks (CB) are an established technique in non-gynecological cytology, but experience in gynecological cytology is still relatively limited. In this study, we compared the diagnostic agreement between liquid-based cytology (LBC) and CB using whole slide digital imaging (WSI). WSI of 82 specimens (41 LBC and 41 CB) were evaluated independently by three observers. The overall agreement was 0.463 for all 82 cases including both LBC and CB, 0.439 for LBC alone, and 0.484 for CB alone. Agreement was highest for HSIL, NILM, cancers and lower for borderline (ASC-US, ASC-H). There was no significant difference in agreement between LBC and CB. WSI of CB can be used for the diagnosis of cervical lesions and may be particularly useful in cases with high atypical cellularity or large hyperchromatic cell groups.

Negri G ，Tauber M ，Pinamonti M ，Golinelli L ，Garofalo M ，Vittadello F ，Capitanio A ... -  《-》

Team Reading (Peer Review) of Suspicious/Positive Slides for Continuous Quality Improvement in Cervical-Vaginal Cytology: A Comparison between Methods and Indicators.

In 2013, the Local Health Unit Roma 2 ex C screening laboratory introduced a new set of indicators for quality assurance. We compare 2 sets of indicators based on routine multiple readings (peer review) for their ability to identify problems in single-reader accuracy. All suspect slides were blindly reviewed by all the cytologists of the laboratory. The standard set of indicators includes interreader Cohen's kappa, positivity rate and atypical squamous cell of undetermined significance/squamous intraepithelial lesion (ASC-US/SIL) ratio. The new set included sensitivity for cervical intraepithelial neoplasia of grade 2 or worse (CIN2+), positive predictive value (PPV) and percentage of positive high-risk (HR)-HPV cases among ASC-US. In order to estimate sensitivity and PPV, we considered all women for whom there was a consensus of negative cytology, negative HR-HPV test, negative colposcopy or negative histology true negative. Kappa values ranged from 0.521 to 0.753, with narrow 95% confidence intervals (CIs). Positivity rate ranged from 73.9 to 85.7 and the ASC-US/SIL ratio from 0.61 to 0.81. Sensitivity for CIN2+ at the low-grade SIL threshold ranged from 85.8 to 94.2, PPV ranged from 14.8 to 19.4, and both had a broad 95% CI. Readers with low sensitivity did not show low kappa values. The percentage proportion of HR-HPV-positives (HR-HPV+) among ASC-US ranged from 39.9 to 43.8% with a narrow 95% CI. The proportion of HR-HPV+ among ASC-US cases is a powerful indicator to address in training.

Placidi A ，Capparucci P ，Di Luzio A ，Manca G ，Mania E ，Filippini T ，Giorgi Rossi P ... -  《-》