High Dynamic Range Dual-Modal White Light Imaging Improves the Accuracy of Tumor Bed Sampling After Neoadjuvant Therapy for Breast Cancer.

OBJECTIVES: Accurate evaluation of residual cancer burden remains challenging because of the lack of appropriate techniques for tumor bed sampling. This study evaluated the application of a white light imaging system to help pathologists differentiate the components and location of tumor bed in specimens. METHODS: The high dynamic range dual-mode white light imaging (HDR-DWI) system was developed to capture antiglare reflection and multiexposure HDR transmission images. It was tested in 60 specimens of modified radical mastectomy after neoadjuvant therapy. We observed the differential transmittance among tumor tissue, fibrosis tissue, and adipose tissue. RESULTS: The sensitivity and specificity of HDR-DWI were compared with x-ray or visual examination to determine whether HDR-DWI was superior in identifying tumor beds. We found that tumor tissue had lower transmittance (0.12 ± 0.03) than fibers (0.15 ± 0.04) and fats (0.27 ± 0.07) (P < .01). CONCLUSIONS: HDR-DWI was more sensitive in identifying fiber and tumor tissues than cabinet x-ray and visual observation (P < .01). In addition, HDR-DWI could identify more fibrosis areas than the currently used whole slide imaging did in 12 samples (12/60). We have determined that HDR-DWI can provide more in-depth tumor bed information than x-ray and visual examination do, which will help prevent diagnostic errors in tumor bed sampling.

Clinical pathologists should limit modifier terms used to denote probability of a diagnosis: a survey-based study.

OBJECTIVE: To examine the probability estimates for modifying terms used by clinical pathologists when interpreting cytologic samples and compare these to probability estimates assigned to these terms by clinicians, and to provide restricted, standardizing terms used in cytology reports. SAMPLE: 49 clinical pathologists and 466 Veterinary Information Network members responded to 2 similar surveys. PROCEDURES: Online surveys were distributed to diplomates of the European College of Veterinary Clinical Pathologists and clinician members of the Veterinary Information Network, made available between March 17, 2022, through May 5, 2022. Respondents assigned a range of probabilities to each of 18 modifier terms used by clinical pathologists to denote probability associated with diagnoses; clinicians identified terms that would affect their treatment decisions in cases of canine lymphoma. Respondents then provided thoughts about restricting and standardizing modifying terms and assigning numeric estimates in reports. RESULTS: 49 clinical pathologists and 466 clinicians provided responses. For many terms, probability ranges agreed between the 2 groups. However, differences in estimated probability inferred by a term existed for at least 6 terms. Modifying terms could be restricted to 7 largely nonoverlapping terms that spanned the range of probabilities. Clinicians preferred having numeric estimates of probability, but clinical pathologists resisted providing such estimates in reports. CLINICAL RELEVANCE: Reducing and standardizing the number of modifying terms to reflect specific probability ranges would reduce disagreement between the clinical pathologist's intended probability range and the clinician's interpretation of a modifying term. This could result in fewer errors in interpretation and better patient care.

Histopathologic and Transcriptomic Profiling Identifies Novel Trophoblast Defects in Patients With Preeclampsia and Maternal Vascular Malperfusion.

Preeclampsia (PE) is a heterogeneous disease for which the current clinical classification system is based on the presence or absence of specific clinical features. PE-associated placentas also show heterogeneous findings on pathologic examination, suggesting that further subclassification is possible. We combined clinical, pathologic, immunohistochemical, and transcriptomic profiling of placentas to develop integrated signatures for multiple subclasses of PE. In total, 303 PE and 1388 nonhypertensive control placentas were included. We found that maternal vascular malperfusion (MVM) in the placenta was associated with preterm PE with severe features and with small-for-gestational-age neonates. Interestingly, PE placentas with either MVM or no histologic pattern of injury showed a linear decrease in proliferative (p63+) cytotrophoblast per villous area with increasing gestational age, similar to placentas obtained from the nonhypertensive patient cohort; however, PE placentas with fetal vascular malperfusion or villitis of unknown etiology lost this phenotype. This is mainly because of cases of fetal vascular malperfusion in placentas of patients with preterm PE and villitis of unknown etiology in placentas of patients with term PE, which are associated with a decrease or increase, respectively, in the cytotrophoblast per villous area. Finally, a transcriptomic analysis identified pathways associated with hypoxia, inflammation, and reduced cell proliferation in PE-MVM placentas and further subclassified this group into extravillous trophoblast-high and extravillous trophoblast-low PE, confirmed using an immunohistochemical analysis of trophoblast lineage-specific markers. Our findings suggest that within specific histopathologic patterns of placental injury, PE can be subclassified based on specific cellular and molecular defects, allowing the identification of pathways that may be targeted for diagnostic and therapeutic purposes.

Submitting High-Quality Clinical Pathology Samples for Best Results.

The reliability of clinical pathology laboratory results is directly related to the sample quality submitted. As such, clinicians must submit the most representative and highest quality sample possible by acquiring, handling, preparing, and shipping samples with utmost care. Cytology and blood smear slides should be evaluated for sufficient densities of intact, well-spread, nucleated cells before submission. Poorly prepared samples may delay or negate results, incurring unnecessary costs for the client and practice. Additionally, all practices should have quality assurance programs that include monitoring of equipment to minimize reporting errors. Maximizing resources is the name of the game!.

Datasets for reporting of soft-tissue sarcoma: recommendations from the International Collaboration on Cancer Reporting (ICCR).

AIMS: Soft-tissue tumours are rare and both accurate diagnosis and proper treatment represent a global challenge. Current treatment guidelines also recommend review by specialised pathologists. Here we report on international consensus-based datasets for the pathology reporting of biopsy and resection specimens of soft-tissue sarcomas. The datasets were produced under the auspices of the International Collaboration on Cancer Reporting (ICCR), a global alliance of international pathology and cancer organisations. METHODS AND RESULTS: According to the ICCR's guidelines for dataset development, an international expert panel consisting of pathologists, a surgical oncologist, and a medical oncologist produced a set of core and noncore data items for biopsy and resection specimens based on a critical review and discussion of current evidence. All professionals involved were subspecialised soft-tissue sarcoma experts and affiliated with tertiary referral centres. Commentary was provided for each data item to explain the rationale for selecting it as a core or noncore element, its clinical relevance, and to highlight potential areas of disagreement or lack of evidence, in which case a consensus position was formulated. Following international public consultation, the documents were finalised and ratified, and the datasets, which included a synoptic reporting guide, were published on the ICCR website. CONCLUSION: These first international datasets for soft-tissue sarcomas are aimed to promote high-quality, standardised pathology reporting. Their adoption will improve consistency of reporting, facilitate multidisciplinary communication, and enhance comparability of data, all of which will help to improve patient's management.

A postmortem study of patients vaccinated for SARS-CoV-2 in Colombia / Autopsias clínicas en pacientes vacunados contra el SARS-CoV-2: estudio post mortem en una población colombiana

Introduction and objective: A new coronavirus produces a disease designated as coronavirus disease 2019 (COVID-19). Vaccination against COVID-19 has resulted in decreased mortality. Postmortems of vaccinated patients play an important part in the forensic analysis of adverse effects after vaccination, which is essential for determining its efficacy and security. The main objective of this study was to describe the results of autopsies of patients vaccinated for SARS-CoV-2 carried out in two major centers in Colombia. Materials and methods: A descriptive cross-sectional study of 121 autopsies was performed following Colombian regulations in two main hospitals in Bogotá, Colombia, between March 1st and April 31st, 2021. Results: 118 of the 121 patients (97.52%) had been vaccinated with CoronaVac (Sinovac); only 3 had received other vaccines. Sudden cardiac death was the leading cause of death, with pulmonary embolism another critical finding. No relation between the cause of death and vaccination against SARS-CoV-2 was found. Conclusions: A clinical autopsy is a vital for an accurate post-mortem diagnosis. Any relation between the SARS-CoV-2 vaccine and the cause of death should be carefully studied in order to provide the general public with evidence-based information about the safety of the vaccination.(AU)

Introducción y objetivo: Un nuevo virus del linaje de los coronavirus produce una enfermedad que se designó como enfermedad por coronavirus 2019 (COVID-19). Actualmente se están aplicando vacunas contra la COVID-19 y han mostrado disminución de la mortalidad en pacientes infectados. El análisis de los efectos adversos tras la vacunación ha sido fundamental para conocer la eficacia y la seguridad tras la administración. El examen forense y patológico de las muertes después de la vacunación representa un componente crítico. El objetivo principal del estudio fue describir una serie de casos de pacientes con inmunización previa contra el SARS-CoV-2 que fallecieron y a los que se les realizó una autopsia clínica en dos centros de referencia en Colombia para estudios post mortem. Materiales y métodos: Se realizó un estudio descriptivo transversal basado en autopsias siguiendo la normatividad colombiana en dos hospitales de alta complejidad de la ciudad de Bogotá, Colombia, durante el período comprendido entre el 1 de marzo de 2021 y el 31 de abril de 2021. Se analizaron un total de 121 autopsias. Resultados: Un total de 118 pacientes (97,52%) fueron vacunados con CoronaVac (Sinovac). La muerte cardíaca súbita fue la principal causa de fallecimiento en la población del estudio, y la embolia pulmonar fue otro hallazgo crítico encontrado en el estudio forense. No se pudo determinar la relación entre las causas de muerte y la vacunación contra el SARS-CoV-2. Conclusiones: La autopsia clínica es una herramienta vital en las instituciones de salud para brindar un diagnóstico post mortem. Consideramos que el estudio de la causalidad de la vacunación contra el SARS-CoV-2 y las muertes es fundamental para futuros estudios, con la intención de proporcionar información basada en evidencia a la población para apoyar el concepto de vacunación segura contra la COVID-19.(AU)

PD-L1 immunoexpression and molecular characterization of histological subtypes in urothelial carcinoma / Inmunoexpresión de PD-L1 y caracterización molecular de subtipos histológicos de carcinoma urotelial

Introduction: Urothelial carcinoma (UC) has histological subtypes whose phenotype reflects their molecular diversity, behavior and response to conventional therapy. Immune checkpoint inhibitors (ICIs) have improved the management of UC by evaluation of PD-L1. In the case of PD-L1 22C3, the initiation of ICI is considered from a combined positive score (CPS) greater than 10. However, UC subtypes with absent PD-L1 22C3 expression in cases with CPS>10 may not respond to these treatments. This study aims to establish a correlation between the PD-L1 immunoexpression and molecular alterations in divergent differentiation and histological subtypes of UC (UC-s). Material and methods: Twenty-six samples of UC were detected from a total of 24 patients. Two pathologists performed separately an assessment of UC-s on hematoxylin–eosin as well as PD-L1 expression. Molecular study of each case was performed by next generation sequencing (NGS). A descriptive analysis of the variables included was conducted. Results: Nine cases (34.61%) showed a CPS>10, some with negative PD-L1 immunoexpression in aggressive UC-s. The molecular study revealed alterations in genes belonging to the p53/cell cycle control, RAS, and DNA repair pathways, among others. None of the alterations were exclusive to any histological subtype. Discussion: Special attention should be paid to CPS>10 cases that include histological subtypes of UC with divergent expression for PD-L1 as they may not respond to treatment with ICI. We recommend examining the proportion and PD-L1 status of each subtype, especially if it has aggressive behavior.(AU)

Introducción: El carcinoma urotelial (CU) presenta subtipos histológicos cuyo fenotipo refleja su diversidad molecular, su comportamiento y su respuesta al tratamiento. Los inhibidores de puntos de control inmunitario (ICI) han mejorado el manejo del CU mediante la evaluación de PD-L1. En el caso de PD-L1 22C3, se considera el inicio de ICI a partir de una puntuación positiva combinada (combined positive score [CPS]) mayor de 10. Sin embargo, los subtipos de CU con ausencia de expresión de PD-L1 22C3 en casos con CPS>10 podrían no responder a estos tratamientos. Este estudio pretende establecer una correlación entre la inmunoexpresión de PD-L1 y las alteraciones moleculares en áreas con diferenciación divergente y subtipos histológicos de CU (CU-s). Material y métodos: Se obtuvieron 26 muestras con CU de 24 pacientes. Dos patólogos evaluaron de manera independiente las CU-s en hematoxilina-eosina y la expresión de PD-L1. Se realizó el estudio molecular mediante Next Generation Sequencing (NGS). Se realizó un análisis descriptivo de las variables incluidas. Resultados: Nueve casos (34,61%) mostraron un CPS>10, algunos con PD-L1 negativo en los CU-s de comportamiento agresivo. El estudio molecular reveló alteraciones en genes de las vías de p53/control del ciclo celular, RAS y reparación del ADN, entre otras. Ninguna alteración fue exclusiva de algún CU-s. Discusión: Debe prestarse especial atención a los casos con CPS>10 que incluyan subtipos histológicos con expresión divergente para PD-L1, ya que podrían no responder al tratamiento con ICI. Se recomienda cuantificar la proporción y el estado de PD-L1 de cada subtipo, especialmente si es de comportamiento agresivo.(AU)

Docencia de pregrado en Anatomía Patológica: Resultados de la encuesta sobre la docencia de la asignatura de Anatomía Patológica en los estudios de pregrado de las facultades de medicina españolas / Undergraduate Pathology: Results of a Survey on Undergraduate Teaching of Pathology in Spanish Medical Schools

Desde la Sociedad Española de Anatomía Patológica se ha realizado una encuesta entre las facultades de medicina españolas con el fin de obtener una imagen global del estado de la docencia de la asignatura de Anatomía Patológica en pregrado valorando los diferentes planes de estudio, la metodología empleada y la dotación de recursos. La encuesta se envió a los coordinadores de la asignatura en las diferentes facultades de medicina españolas a través de un formulario creado con la herramienta Formularios de Google.El 62% de las 55 unidades docentes encuestadas participaron en el estudio (76% universidades públicas y 24% privadas). Prácticamente en la mitad de los casos, la Anatomía Patológica se imparte como asignatura única, y en la otra mitad como una asignatura general y otra especial. Solo un 18% de las facultades contempla la asignatura especial integrada con otras asignaturas clínicas, y en general, solo en un 55% de los centros con Anatomía Patológica Especial, el contenido está coordinado con el de otras asignaturas clínicas.Los resultados de este estudio ponen en evidencia la heterogeneidad de la formación ofrecida en la asignatura de Anatomía Patológica para los estudiantes de Medicina en las diversas universidades españolas. Solamente planteando una asignatura en pregrado que sea atractiva y estimulante podremos motivar suficientemente a los estudiantes para elegir Anatomía Patológica como especialidad. En este artículo presentamos los resultados de la encuesta con todos los comentarios recogidos y las reflexiones planteadas a partir de los mismos. Las principales medidas propuestas están relacionadas con insistir en el carácter asistencial de la especialidad y en ofrecer rotaciones prácticas en los servicios de Anatomía Patológica.(AU)

In order to ascertain the present state of undergraduate pathology teaching in Spain, the Spanish Society of Pathology sent a survey to the coordinators of the subject in every Medical School. The survey consisted of a form created using Google Forms tool and covered various aspects of teaching, such as the different syllabi, methodology and resources.62% of the 55 Medical Schools contacted participated in the study (76% public and 25% private). In about half of cases, Pathology was taught as a single subject, while in the rest it was divided into General and Special Pathology. Only 18% integrated other clinical subjects into Pathology teaching and only 55% coordinated the timing of the course in order to coordinate with the content of other clinical subjects.We present the results of the survey together with all the accompanying comments and reflections, which highlight the heterogeneity of the Pathology syllabus in Spanish Medical Schools. We consider that if undergraduate Pathology is taught in an attractive, stimulating and clinically relevant manner, more students would be motivated to choose Pathology as their future speciality. Our main recommendations would be to emphasize the clinical application of Pathology and offer opportunities to gain practical, hands-on experience in Pathology departments.(AU)

Recommendations for the use of biomarkers for head and neck cancer, including salivary gland tumours: A Consensus of the Spanish Society of Medical Oncology and the Spanish Society of Pathology / Recomendaciones para el uso de biomarcadores para cáncer de cabeza y cuello, incluyendo tumores de glándulas salivares: consenso de la Sociedad Española de Oncología Médica y la Sociedad Española de Patología

The treatment of head and neck and salivary gland tumours is complicated and is constantly evolving. Prognostic and predictive indicators of response to treatment are enormously valuable for designing individualized therapies, which justifies their research and validation. Some biomarkers, such as p16, Epstein–Barr virus, PD-L1, androgen receptors and HER-2, are already used routinely in clinical practice. These biomarkers, along with other markers that are currently under development, and the massively parallel sequencing of genes, ensure future advances in the treatment of these neoplasms.In this consensus, a group of experts in the diagnosis and treatment of tumours of the head and neck and salivary glands were selected by the Spanish Society of Pathology (Sociedad Española de Anatomía Patológica – SEAP) and the Spanish Society of Medical Oncology (Sociedad Española de Oncología Médica – SEOM) to evaluate the currently available information and propose a series of recommendations to optimize the determination and daily clinical use of biomarkers.(AU)

El tratamiento de los tumores de cabeza y cuello y de glándulas salivales es complejo, y evoluciona de forma constante. Los indicadores pronósticos y predictivos de respuesta al tratamiento son enormemente valiosos para diseñar terapias individualizadas, lo que justifica su investigación y validación. Algunos biomarcadores como p16, el virus de Epstein-Barr, PD-L1, los receptores de andrógenos o HER-2, ya se utilizan de manera rutinaria en la práctica clínica. Estos biomarcadores, junto con otros marcadores que están actualmente en desarrollo, y la secuenciación masiva de genes, aseguran los futuros avances en el tratamiento de estas neoplasias. En este consenso, un grupo de expertos en el diagnóstico y tratamiento de los tumores de cabeza y cuello y glándulas salivales seleccionado por la Sociedad Española de Anatomía Patológica (SEAP) y la Sociedad Española de Oncología Médica (SEOM) evalúan la información actualmente disponible y proponen una serie de recomendaciones para optimizar la determinación y utilización en la práctica clínica diaria de los biomarcadores.(AU)

Expert consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology on the determination of biomarkers in pancreatic and biliary tract cancer / Consenso de Expertos de la Sociedad Española de Patología y la Sociedad Española de Oncología Médica sobre la determinación de biomarcadores en el cáncer de páncreas y vías biliares

Pancreatic cancer and biliary tract cancer have a poor prognosis. In recent years, the development of new diagnostic techniques has enabled the identification of the main genetic alterations involved in the development of these tumours. Multiple studies have assessed the ability to predict response to treatment of certain biomarkers, such as BRCA in pancreatic cancer, IDH1 or FGFR2 in biliary tract cancer and microsatellite instability or NTRK fusions in an agnostic tumour fashion. In this consensus, a group of experts selected by the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Pathology (SEAP) reviewed the role played by these mutations in the process of carcinogenesis and their clinical implications. Based on their results, a series of recommendations are made to optimize the determination of these biomarkers and thus help standardize the diagnosis and treatment of these tumours.

El cáncer de páncreas y el de vías biliares son tumores de mal pronóstico. En los últimos años, el desarrollo de nuevas técnicas diagnósticas de biología molecular ha permitido conocer las principales alteraciones génicas implicadas en el desarrollo de estos tumores. Múltiples estudios han evaluado el carácter predictivo de respuesta a tratamiento de determinados biomarcadores, como BRCA en cáncer de páncreas, IDH1 y FGFR2 en tumores de vía biliar; y la inestabilidad de microsatélites y las fusiones de NTRK, para predecir la respuesta al tratamiento. En este consenso, un grupo de expertos seleccionado por la Sociedad Española de Oncología Médica (SEOM) y la Sociedad Española de Anatomía Patológica (SEAP) ha revisado el papel que desempeñan estas mutaciones en el proceso de carcinogénesis y sus implicaciones clínicas. Como resultado, en este artículo se proponen una serie de recomendaciones para optimizar la determinación de estos biomarcadores, con el fin de fomentar la estandarización en el diagnóstico y el tratamiento de estos tumores.(AU)

Recommendations for optimizing the use of cytology in the diagnosis and management of patients with lung cancer / Recomendaciones para optimizar el uso de la citología en el diagnóstico y manejo de pacientes con cáncer de pulmón

Non-small cell lung cancer (NSCLC) is one of the oncological entities with the greatest evolution in molecular diagnosis due to the large number of diagnostic biomarkers and new treatments approved by international regulatory agencies. An accurate, early diagnosis using the least amount of tissue is the goal for the establishing and developing precision medicine for these patients. Rapid on-site evaluation (ROSE) provides cytological samples of optimal quantity and quality for a complete diagnosis of NSCLC. The usefulness of cytological samples has been demonstrated, not only for massive parallel sequencing but also for the quantification of the expression of programmed death-ligand 1 (PD-L1) and tumour mutational burden (TMB).Pre-analytical, analytical, and post-analytical recommendations are made for the management and appropriate use of cytological samples in order to obtain all the information necessary for the diagnosis and treatment of patients with NSCLC according to current quality parameters.(AU)

El cáncer de pulmón de célula no pequeña es la patología oncológica que más está evolucionando con respecto al diagnóstico molecular por la ingente cantidad de biomarcadores diagnósticos y nuevos tratamientos aprobados por las agencias regulatorias internacionales. La incorporación de la valoración in situ (Rapid On Site Evaluation) de las muestras obtenidas por punción-aspiración con aguja fina permite la obtención de muestras citológicas en cantidad y calidad óptimas para acometer un diagnóstico completo del cáncer de pulmón de célula no pequeña. La citología ha demostrado su utilidad en la secuenciación masiva, la determinación de la expresión del ligando 1 de muerte programada (programmed death-ligand 1) y de la carga mutacional (tumour mutational burden).En este documento se establecen recomendaciones preanalíticas, analíticas y postanalíticas que permiten manejar y aprovechar adecuadamente la muestra citológica para obtener toda la información necesaria para el diagnóstico y tratamiento del paciente con cáncer de pulmón de célula no pequeña con los parámetros de calidad exigibles hoy en día.(AU)

Mesotelioma papilar bien diferenciado: descripción de tres casos y revisión bibliográfica / Well differentiated papillary mesothelioma: description of three case reports and review of the literature

El mesotelioma papilar bien diferenciado (MPBD) es una neoplasia muy infrecuente que afecta fundamentalmente a mujeres en edad reproductiva. La localización más habitual es el peritoneo y se trata de un hallazgo incidental, con un pronóstico generalmente favorable. Presentamos tres casos diagnosticados de manera incidental, en el trascurso de una intervención quirúrgica de causas diversas, que se presentaron como lesiones exofíticas peritoneales no detectadas en el estudio de imagen prequirúrgico. Es importante tener presente esta entidad para diferenciarla de otras neoplasias de pronóstico y evolución desfavorable, como el mesotelioma maligno o carcinomas primarios y metastásicos. Estudios recientes le confieren al MPBD un perfil inmunohistoquímico y molecular específico que permiten una mayor precisión diagnóstica de la entidad.(AU)

Well Differentiated Papillary Mesothelioma (MPBD) is a very rare neoplasm that mainly affects women of reproductive age. The most common location is the peritoneum and it is an incidental finding, with a generally favorable prognosis. We present three cases diagnosed incidentally, in the course of a surgical intervention of various causes, which presented as peritoneal exophytic lesions not detected in the pre-surgical imaging study. It is important to keep this entity in mind, to differentiate it from other neoplasms with an unfavorable prognosis and evolution, such as Malignant Mesothelioma or primary and metastatic carcinomas. Recent studies give the MPBD a specific immunohistochemical and molecular profile that allow a greater diagnostic precision of the entity.(AU)

Dataset for the reporting of neoplasms of the heart, pericardium, and great vessels: recommendations from the International Collaboration on Cancer Reporting (ICCR).

The International Collaboration on Cancer Reporting (ICCR) was founded by major pathology organizations from around the world to produce internationally standardized and evidence-based datasets for pathologists' reporting of cancer. Its goal is to improve cancer patient outcomes worldwide and to advance international benchmarking in cancer management. The ICCR cancer dataset development schedule is aligned with revisions of the WHO Classification of Tumours ("Blue Book") series, and in 2015 ICCR developed an initial series of thoracic datasets including a dataset for neoplasms of the heart, pericardium, and great vessels. This edition has now been updated to align with the 2021 WHO Blue Book series. An expert panel was convened to review and revise the dataset. While the majority of ICCR datasets are focused on malignant tumors, the scope of this dataset includes a number of benign tumors and tumor-like entities because of the rarity of cardiac malignancies and the serious implications of even histologically benign lesions. Due to the rarity of cardiac tumors, evidence in support of reporting elements is limited.

The World Health Organization Reporting System for Lung Cytopathology.

The International Academy of Cytology has joined with the International Agency for Research on Cancer (IARC) to bring together a group of experts in lung cytopathology to develop a WHO Reporting System for Lung Cytopathology (WHO System). This WHO System defines five categories for reporting lung cytopathology, that is, "Insufficient"/"Inadequate"/"Non-diagnostic," "Benign," "Atypical," "Suspicious for malignancy," and "Malignant," each with a clear descriptive term for the category, a definition, a risk of malignancy and a suggested management algorithm. The key diagnostic cytopathology features of each of the lesions within each category have been established by consensus and will be presented more fully in a subsequent IARC e-book and published hard cover book.The WHO System provides the best practice application of ancillary testing, including immunocytochemistry and molecular pathology, and provides a review to guide sampling and processing techniques to optimize the handling and preparation of the cytopathology sample emphasizing the cytomorphological differential diagnosis to aid low-resourced settings. The authors recognize that local medical and pathology resources will vary, particularly in low- and middle-income countries, and have developed the WHO System to make it applicable worldwide based on cytomorphology with options for further diagnostic management of the patient.The online WHO System provides a direct link to the WHO Tumour Classification for Thoracic Tumours 5th Edition. It will raise the profile and use of cytopathology by increasing awareness of its current role and its potential role in the era of personalized medicine based on molecular pathology utilizing "small biopsies." Ultimately, the System will improve patient care and outcomes.This System aims to improve and standardize the reporting of cytopathology, facilitate communication between cytopathologists and clinicians and improve patient care. The System is based on the current role of lung cytopathology and synthesizes the existing evidence while highlighting areas requiring further research and the future potential role of lung cytopathology.

Comparing Whole Slide Imaging and Light Microscopy to Identify Tumor in en face Frozen Sections.

OBJECTIVE: To assess accuracy of whole slide imaging (WSI) in the interpretation of permanent and frozen sections in surgical pathology and the identification of tumors in cutaneous en face frozen sections. METHODS: Twenty glass slides containing cutaneous en face frozen sections were selected from twenty cases of keratinocyte carcinomas treated with Mohs micrographic surgery. Ten slides contained tumor and ten did not. A blinded dermatologic surgeon used traditional light microscopy (LM) to assess physical slides for tumor presence and type, while noting the confidence (scale 1-10) and time (min) in making the determination. After a seven-day washout period, the surgeon repeated this process using WSI of the same slides, each de-identified and scanned at 20x using the Aperio AT2 (Leica Biosystems). RESULTS: Percent agreement between LM and WSI was 100%, with Cohen's kappa of 1.0. The average time taken to determine tumor presence was significantly greater using WSI than LM. Similarly, the surgeon was significantly more confident using LM than WSI. CONCLUSION: This proof-of-concept study suggests that diagnostic concordance is excellent between LM and WSI in the evaluation of Mohs frozen sections. However, WSI was cumbersome to use, not ergonomic, and required significantly more time.