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

The use of telepathology in veterinary medicine: a scoping review

Telepathology, as a subset of teleconsulting, is pathology interpretation performed at a distance. Telepathology is not a new phenomenon, but since ~2015, significant advances in information technology and telecommunications coupled with the pandemic have led to unprecedented sophistication, accessibility, and use of telepathology in human and veterinary medicine. Furthermore, telepathology can connect veterinary practices to distant laboratories and provide support for underserved animals and communities. Through our scoping review, we provide an overview of how telepathology is being used in veterinary medicine, identify gaps in the literature, and highlight future areas of research and service development. We searched MEDLINE, CAB Abstracts, and the gray literature, and included all relevant literature. Despite the widespread use of digital microscopy in large veterinary diagnostic laboratories, we identified a paucity of literature describing the use of telepathology in veterinary medicine, with a significant gap in studies addressing the validation of whole-slide imaging for primary diagnosis. Underutilization of telepathology to support postmortem examinations conducted in the field was also identified, which indicates a potential area for service development. The use of telepathology is increasing in veterinary medicine, and pathologists must keep pace with the changing technology, ensure the validation of innovative technologies, and identify novel uses to advance the profession.

Pathology and Telepathology Methods in the Child Health and Mortality Prevention Surveillance Network

This manuscript describes the Child Health and Mortality Prevention Surveillance (CHAMPS) network approach to pathologic evaluation of minimally invasive tissue sampling (MITS) specimens, including guidelines for histopathologic examination and further diagnostics with special stains, immunohistochemistry, and molecular testing, as performed at the CHAMPS Central Pathology Laboratory (CPL) at the Centers for Disease Control and Prevention, as well as techniques for virtual discussion of these cases (telepathology) with CHAMPS surveillance locations. Based on review of MITS from the early phase of CHAMPS, the CPL has developed standardized histopathology-based algorithms for achieving diagnoses from MITS and telepathology procedures in conjunction with the CHAMPS sites, with the use of whole slide scanners and digital image archives, for maximizing concurrence and knowledge sharing between site and CPL pathologists. These algorithms and procedures, along with lessons learned from initial implementation of these approaches, guide pathologists at the CPL and CHAMPS sites through standardized diagnostics of MITS cases, and allow for productive, real-time case discussions and consultations.

The utility of cell blocks for international cytopathology teleconsultation by whole slide imaging

INTRODUCTION

Telecytology for second opinion consultation has largely been limited by technical issues, such as the inability to focus well on cellular material. Nevertheless, international telecytology consultation was undertaken at our institution with partners in China and Italy. To overcome issues with scanning cytology slides, we adopted a cell-block (CB) preference for teleconsultation.

METHODS

Telecytology consultation cases received over a 7.5-year period were retrospectively reviewed. Cytology glass slides were scanned without Z-stacking using different whole slide scanners. For one referring site, only haematoxylin-eosin-stained CBs were scanned, as well as immunostains requested by consultants. For another host centre, aspirate smears were also scanned in some cases.

RESULTS

A total of 51 non-gynaecological cases (44 CB only) were evaluated from 48 patients. The specimens included pleural fluids (19), pancreas (14), lymph nodes (6), peritoneal fluids (2) and miscellaneous samples (10). The cytological diagnoses spectrum included 16 (31.37%) cases positive for malignancy, 7 (13.72%) positive for neoplasm, 6 (11.76%) suspicious for malignancy, 10 (19.60%) atypical, 10 (19.60%) negative for malignancy and 2 (3.92%) non-diagnostic. In 42 (82.35%) cases, immunocytochemistry was requested. Turn-around-time ranged from 1.5 to 306 hours.

CONCLUSIONS

Our experience shows that international telecytology for consultation purposes involving non-gynaecological cases is feasible. A second opinion interpretation was rendered in the majority (64.7%) of cases. Utilising CB only for cytology consultations by whole slide imaging solved focus issues that typically plague evaluation of cytology aspirate smears.

Diagnostic Validation of a Whole-Slide Imaging Scanner in Cytological Samples: Diagnostic Accuracy and Comparison With Light Microscopy

Digital slides created by whole-slide imaging scanners can be evaluated by pathologists located in remote sites, but the process must be validated before this technology can be applied to routine cytological diagnosis. The aim of this study was to validate a whole-slide imaging scanner for cytological samples. Sixty cytological samples, whose diagnoses were confirmed by gold-standard examinations (histology or flow cytometry), were digitalized using a whole-slide imaging scanner. Digital slides and glass slides were examined by 3 observers with different levels of cytopathological expertise. No significant differences were noted between digital and glass slides in regard to the number of cases correctly diagnosed, or the sensitivity, specificity, or diagnostic accuracy, irrespective of the observers’ expertise. The agreements between the digital slides and the gold-standard examinations were moderate to substantial, while the agreements between the glass slides and the gold-standard examinations were substantial for all 3 observers. The intraobserver agreements between digital and glass slides were substantial to almost perfect. The interobserver agreements when evaluating digital slides were moderate between observers 1 and 2 and between observers 1 and 3 while they were substantial between observers 2 and 3. In conclusion, our study demonstrated that the digital slides produced by the whole-slide imaging scanner are adequate to diagnose cytological samples and are similar among clinical pathologists with differing levels of expertise.

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.

The Empirical Foundations of Telepathology: Evidence of Feasibility and Intermediate Effects

INTRODUCTION

Telepathology evolved from video microscopy (i.e., "television microscopy") research in the early 1950s to video microscopy used in basic research in the biological sciences to a basic diagnostic tool in telemedicine clinical applications. Its genesis can be traced to pioneering feasibility studies regarding the importance of color and other image-based parameters for rendering diagnoses and a series of studies assessing concordance of virtual slide and light microscopy diagnoses. This article documents the empirical foundations of telepathology.

METHODS

A selective review of the research literature during the past decade (2005-2016) was conducted using robust research design and adequate sample size as criteria for inclusion.

CONCLUSIONS

The evidence regarding feasibility/acceptance of telepathology and related information technology applications has been well documented for several decades. The majority of evidentiary studies focused on intermediate outcomes, as indicated by comparability between telepathology and conventional light microscopy. A consistent trend of concordance between the two modalities was observed in terms of diagnostic accuracy and reliability. Additional benefits include use of telepathology and whole slide imaging for teaching, research, and outreach to resource-limited countries. Challenges still exist, however, in terms of use of telepathology as an effective diagnostic modality in clinical practice.

Cell Block Preparation versus Liquid-Based Thin-Layer Cervical Cytology: A Comparative Study Evaluating Human Papillomavirus Testing by Hybrid Capture-2/Cervista, in situ Hybridization and p16 Immunohistochemistry

OBJECTIVE

Cell block (CB) preparations from residual liquid-based Pap samples have been shown to be of diagnostic value. In this study we evaluated human papillomavirus (HPV) in situ hybridization (ISH) and p16 immunohistochemistry (IHC) on CB preparations and compared the results with the primary diagnosis and standard HPV tests.

DESIGN

In total, 197 HE-stained CB slides prepared from CBs from residual Pap samples (152 ASCUS, 2 ASC-H, 32 LGSIL, 4 HGSIL, 1 AGUS and 6 normal) were analyzed. Hybrid Capture-2 (HC-2)/Cervista testing and HPV ISH and p16 IHC were performed on the CB samples. The test performance characteristics were compared with HPV and p16 assay performances.

RESULTS

The cellular architecture was well maintained in CBs with excellent consistency. HPV ISH testing had an excellent concordance with the HC-2/Cervista methods (85%) with high sensitivity (82.6%; 95% CI 75.9, 89.4) and specificity (89.3%). Of all the p16 tests, 38% were positive (60 out of 159 samples). The overall concordance between p16 and HC-2/Cervista (64%), or between p16 and ISH (68%), was lower than the concordance between ISH and HC-2/Cervista (85%).

CONCLUSIONS

HPV ISH and p16 IHC testing is feasible, cost effective and practical. A combination of the two tests would ultimately improve diagnostic accuracy, leading to better therapeutic decisions.

Comparison of the diagnostic utility of digital pathology systems for telemicrobiology

INTRODUCTION

Telemicrobiology is a growing component of clinical microbiology informatics. However, few studies have been performed to assess the diagnostic utility of telemicroscopy systems in evaluating infectious agents.

OBJECTIVE

Evaluate multiple contemporary digital pathology platforms for use in diagnostic telemicrobiology.

MATERIALS AND METHODS

A mix of thirty cases that included viral, bacterial, fungal, and parasitological findings were evaluated by four experts using ×40 whole slide imaging (WSI) scans, ×83 oil-immersion WSI scans, ×100 oil-immersion WSI scans, digital photomicrographs, and glass slides.

RESULTS

The ×83 WSI, ×100 WSI, and photomicrograph interpretations were not significantly different in quality and accuracy when compared to glass slide interpretations. The ×40 WSI interpretations were of lower quality and were more likely to be incorrect when compared to glass slide interpretations.

CONCLUSIONS

In this study, high magnification, oil-immersion digital pathology platforms are better suited to support telemicrobiology applications and yield interpretations on par with glass slide evaluations.