Rare variants of primary liver cancer: Fibrolamellar, combined, and sarcomatoid hepatocellular carcinomas.

Hepatocellular carcinoma (HCC) constitutes 80% of all primary liver cancers. Based on key developments in the understanding of its carcinogenesis and the advancement of treatment options, detailed algorithms and practice guidelines have been published to guide the clinical management of HCC. Furthermore, several subclasses of HCC have been described based on molecular profiles and linked to pathological characteristics, clinical features, and disease aggressiveness. Most recently, the combination of the checkpoint inhibitor atezolizumab plus bevacizumab has significantly increased treatment response in the first line systemic treatment of HCC. Unfortunately, rare HCC variants, in particular fibrolamellar liver cancer (FLC), combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CCA), and sarcomatoid hepatocellular carcinoma (sHCC), were excluded from phase III studies. Therefore, data for decision-making and treatment allocation for these distinct entities, representing 1-5% of all primary liver cancers, is scarce. Moreover, most of the knowledge available for these rare HCC variants is based on registry data and retrospective studies. In this position paper, we briefly summarize the current clinical knowledge regarding FLC, cHCC-CCA, and sHCC. Based on our summary, we propose future clinical research activities within the framework of the European Reference Network on Hepatological Diseases (ERN RARE-LIVER).

A retrospective analysis of pleural effusion specimens based on the newly proposed International System for Reporting Serous Fluid Cytopathology.

BACKGROUND: Recently, the International System for Reporting Serous Fluid Cytopathology (TIS) has been established, with an aim to standardize reporting and guide clinical decision making. METHODS: The cytological and clinicopathological data of pleural effusions were retrieved from the pathology database and electronic medical records. All specimens were evaluated and reclassified in accordance with the TIS recommendations. Finally, the risk of malignancy (ROM) and performance parameters were measured. RESULTS: A total of 2454 pleural effusion specimens were included, among which 30 (1.2%), 1670 (68.1%), 151 (6.2%), 54 (2.2%) and 549 (22.4%) patients were classified into non-diagnostic (ND), negative for malignancy (NFM), atypia of undetermined significance (AUS), suspicious for malignancy (SFM) and malignancy (MAL) groups, respectively. The most commonly diagnosed malignancies were lung cancer (48.4%), ovary cancer (10.2%), breast cancer (7.5%), and 21.3% unknown primary site (UPS). Among the 36 UPS patients, the most common site of origin was lung (36.1%), followed by ovary (13.9%) and breast (11.1%) via immunocytochemistry of cell block. The calculated ROM values were 26.7%, 12%, 62.3%, 77.8% and 100% for ND, NFM, AUS, SFM and MAL groups, respectively. When considering MAL as the only positive group, the diagnostic accuracy, sensitivity, specificity, positive and negative predictive values were determined to be 95.2%, 81.9%, 100%, 100% and 93.6%, respectively. CONCLUSION: The newly proposed TIS is an easy-to-master, user-friendly, and standardized classification system, especially when applying on pleural effusions. An adequate serous sample, application of immunocytochemistry, review of cytomorphological data and past medical history could enhance the accuracy of cytological diagnosis.

Recommendations of the European Advisory Committee of Cytotechnology and European Federation of Cytology Societies for Training and Education of Cytotechnologists in Europe.

BACKGROUND: Faced with changes in cytodiagnostics, cervical cancer screening programs, the introduction and application of new methods, the cytotechnological educational program requires the necessary changes and additions. Insufficient, uneven as well as inaccessible education of cytotechnologists in European countries was the basis for making these recommendations. SUMMARY: The results of previous research and publications related to the currently available education of cytotechnologists in Europe, the needs and suggestions were given by the European Advisory Committee of Cytotechnology (EACC) and European Federation of Cytology Societies (EFCS) for optimal education of future generations of cytotechnologists were used in the preparation of these recommendations. The EACC and EFCS propose a 1-year education and training program divided into 3 modules: gynecological, nongynecological exfoliative, and fine-needle aspiration cytology. Training programs should be organized by an accredited university, preferably a combination of internal education in a cytology laboratory and theoretical education at the university. Cytopathologists and cytotechnologists with at least 5 years of work experience in cytodiagnostics should participate in education. Upon completion of the training program, the EACC and EFCS propose an official name: EFCS certified cytotechnologist. Key Messages: The EACC and EFCS believe that it is extremely important that these recommendations are recognized and implemented by institutions that provide education for cytotechnologists so that they can meet the growing requirements of the profession with their acquired knowledge and competencies.

From Operating Table to Laboratory Bench: The Path Toward Metastasis Research from the Clinical Setting.

Presence of metastasis translates unequivocally into worse prognosis for our patients. Translational medicine has been our response to offer patients better therapeutic options. This chapter aims to provide an overview for clinicians to send the necessary metastatic tissue on the right path toward the laboratory bench, overcoming biases and possible data misinterpretations derived from poor sample quality.

Implementation of the International Academy of Cytology Yokohama standardized reporting for breast cytopathology: An 8-year retrospective study.

BACKGROUND: The International Academy of Cytology (IAC) Yokohama reporting system was recently proposed to serve as a standardized diagnostic platform for the cytological interpretation of breast fine needle aspiration biopsy (FNAB). Five cytological categories were suggested, linked to a certain risk of malignancy (ROM). The aim of this study was to assess the potency of this newly proposed reporting guideline, with a review of literatures. METHODS: This is a retrospective study over 8-year duration in which all the breast FNABs performed in our institution were recategorized in accordance to the IAC Yokohama reporting system. Kappa coefficient was used to evaluate the agreement between the proposed cytological category and corresponding histological diagnosis, with the level of significance set at 5%. Cyto-histopathological correlation and its diagnostic performance were also assessed. RESULTS: A total of 1136 breast FNABs were analyzed, including 31 repeat FNABs. Of these, 521 (47.1%) cases had matched histopathological results. Respective ROM for each category was: "insufficient" 13.6%, "benign" 0.4%, "atypical" 25.0%, "suspicious" 85.7%, and "malignant" 100%. There was substantial agreement (κ=0.757) between cytology and histopathological results. Our data revealed a high-diagnostic specificity, sensitivity, positive and negative predictive value of 99.3% (95% CI: 97.6%-99.9%), 94.2% (95% CI: 87.9%-97.9%), 98.0% (95% CI: 92.5%-99.5%), 98.0% (95% CI: 96.1%-99.1%) respectively when both the "suspicious" and "malignant" cases were considered as positive tests, with area under the curve of 0.993. CONCLUSIONS: The IAC Yokohama system is a reliable, evidence-based, and standardized reporting system that helps to facilitate communication among cytopathologists, radiologists, and surgeons toward individualized patient management.

Application of the Milan System for Reporting Pediatric Salivary Gland Cytopathology: Analysis of histologic follow-up, risk of malignancy, and diagnostic accuracy.

BACKGROUND: The diagnosis and management of salivary gland tumors in pediatric patients can be challenging. The utility of fine-needle aspiration (FNA) cytopathology and the performance of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) in this age group have not been systematically assessed. The paucity of data has contributed to the controversial role of FNA cytopathology in the presurgical management of these patients. METHODS: The authors retrospectively analyzed 104 pediatric salivary gland FNAs (2000-2020). A correlation with the available histopathologic follow-up (n = 54) was performed. The distribution percentages, the risk of neoplasm (RON), and the risk of malignancy (ROM) were assessed for each category of the MSRSGC. RESULTS: The overall sensitivity, specificity, negative predictive value, and positive predictive value of pediatric salivary gland FNAs were 80%, 97%, and 92%, respectively. The RON values for the nondiagnostic, nonneoplastic, atypia of undetermined significance, benign neoplasm, salivary gland neoplasm of uncertain malignant potential, suspicious for malignancy, and malignant categories were 60%, 11%, 100%, 100%, 100%, 100%, and 100%, respectively, whereas the ROM values were 0%, 11%, 100%, 6%, 67%, 100%, and 100%, respectively. The percentage of nonneoplastic FNAs was greater in comparison with the adult population (52% vs 8%). All neoplasms in patients aged 0 to 10 years were malignant, whereas benign neoplasms occurred only in patients aged ≥11 years; this supported an inverse correlation between age and malignancy rate in salivary gland neoplasms. CONCLUSIONS: FNA cytopathology demonstrates excellent diagnostic performance in differentiating malignant and benign pediatric salivary gland lesions. The MSRSGC is a valuable tool for standardization of the reporting and preoperative risk stratification of these lesions.

Effect of the Paris system for reporting urinary cytology with histologic follow-up.

BACKGROUND: The Paris system (TPS) for Reporting Urinary Cytology provides a standardized reporting system whose main focus is the diagnosis of high-grade urothelial carcinoma (HGUC). We conducted a study to see the impact of The Paris System on our cytologic diagnoses with associated histology. MATERIALS AND METHODS: We reviewed our pathology database regarding urinary specimens in the year before implementation of The Paris System and the year after. We gathered the data regarding cytologic diagnosis and concurrent/subsequent histology. RESULTS: Over a 1-year period from 2016-2017, 486 urine cytology specimens were identified before implementation of The Paris System and diagnosed as follows: 83% benign/negative, 10% atypical, 2% suspicious, 5% HGUC, 0.2% low grade urothelial neoplasm (LGUN), and 0.2% unsatisfactory. Over a next 1-year period from 2017 to 2018, 602 specimens used TPS and diagnosed as follows: 85% negative for HGUC, 6% atypical, 3% suspicious, 4% HGUC, 0.17% LGUN, and 2% unsatisfactory. Although, not listed as a standardized category in The Paris System, our institution used "Negative for high-grade, cannot rule out low-grade urothelial neoplasm (NHL)" as a subcategory of Negative for HGUC. 4% of the cases fell into this category. Focusing on the Atypical category before TPS, histology was available in 15/49 (31%) cases. Of these, 40% had HGUC. Regarding the Atypical category after TPS, histology was available in 21/36 (58%) cases. Of these, 52% were HGUC. For the NHL category, concurrent histology was available in 13/26 (50%) cases. Of these, 67% were low grade urothelial neoplasms. CONCLUSION: Our study showed that TPS lowered the rate of Atypical from 10% to 6%. After the implementation of TPS, Atypical corresponded to a higher rate of high-grade urothelial carcinoma. Also, the NHL subcategory had a high positive predictive value for diagnosing low grade urothelial neoplasms.

Two-Year Experience of the Implementation of the Milan for Reporting Salivary Gland Cytopathology at a Private Medical Laboratory.

This study aimed to present the 2-year experience of the implementation of the Milan System for Reporting Salivary Gland Cytopathology at Alpha Prolipsis Medical Laboratories, a private medical laboratory located in Athens, Greece. A totaI of 102 Fine Needle Aspirations (FNAs) performed since 2018 were included in the study. Reports were issued according to the Milan System for Reporting Salivary Gland Cytopathology. Aspirates were prepared with both conventional and liquid-based cytological methods and were evaluated by two or three Board-certified cytopathologists. Diagnostic reproducibility and accuracy were evaluated. All cases included in this study had histologic follow-up. The diagnostic accuracy of FNA for differentiating between benign and malignant disease according to MSRSGC classification was 93.3%, the specificity was 97.5% and the sensitivity was 82.2%. The positive and negative predictive values were 93.2 and 87.2%, respectively. Our results show that FNA is a valuable examination technique in the preoperative evaluation of salivary gland lesions. The integration of the 2018 Milan System for Reporting Salivary Gland Cytopathology is effective, with an overall accuracy around 95%.

Cytohistological correlation in serous effusions using the newly proposed International System for Reporting Serous Fluid Cytopathology: Experience of an oncological center.

BACKGROUND: Cytological analysis is part of the initial etiological evaluation of serous effusions. The newly proposed International System for Reporting Serous Fluid Cytopathology (ISRSFC) aims to standardize reporting. METHODS: All pleural and peritoneal effusion samples admitted for cytological analysis at our institution between 2012 and 2016, and pericardial effusion samples admitted between 2008 and 2018, were reviewed and reclassified according to the ISRSFC. Risk of malignancy (ROM) and performance parameters were calculated. RESULTS: 1496 pleural effusion samples were reclassified: 12(0.8%) non-diagnostic (ND), 944(63.1%) negative for malignancy (NFM), 9(0.6%) atypia of undetermined significance (AUS), 54(3.6%) suspicious of malignancy (SFM) and 477(31.9%) malignant (M). 64 pericardial effusion samples were reclassified: 23(35.9%) NFM, 1(1.6%) AUS, 4(6.3%) SFM and 36(56.2%) M. 763 peritoneal effusion samples were reclassified: 5(0.7%) ND, 457(59.9%) NFM, 12(1.6%) AUS, 37(4.8%) SFM and 252(33%) M. The ROM was, respectively, for each of the aforementioned categories, 57.1%, 23.9%, 50%, 76.2%, 100% in pleural effusions, 100%, 26.3%, 62.5%, 91.7%, 100% in peritoneal effusions and 0% for NFM, 0% for AUS and 100% for M in pericardial effusions. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were, respectively, 61.6%, 100%, 100%, 73.3%, 81.3% for pleural, 100%, 100%, 100%, 100%, 100% for pericardial and 61.2%, 100%, 100%, 70%, 79.7% for peritoneal effusion samples. CONCLUSION: Serous effusion cytology has a high specificity and positive predictive value and a modest sensitivity and negative predictive value, supporting its role in confirming the diagnosis of malignancy. The ISRSFC will increase standardization and reproducibility in reporting, leading to improved clinical decision-making.

The International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology: Analysis and discussion of the response to a web-based survey.

BACKGROUND: A group of international experts in breast fine needle aspiration biopsy (FNAB) cytopathology, supported by the International Academy of Cytology (IAC), drafted a comprehensive system for reporting breast FNAB cytopathology in 2017-2018. The editorial team produced a survey to assess the international response to the proposed category structure, definitions, and management recommendations in this draft. METHODS: A web-based survey of 186 questions was generated using the Qualtrics software package (Provo, Utah) supported by the Division of Information Technology at the University of Wisconsin-Madison. The survey was advertised widely-including through the IAC, American Society of Cytopathology, Japanese Society of Clinical Cytology, Papanicolaou Society of Cytopathology, and Australian Society of Cytology and to audiences at national and international meetings-and was available from April to June 2018. The data obtained from the 265 respondents was assessed by the editorial team. RESULTS: The survey provided a snapshot of the current role and use of breast FNAB and the international variations. Demographic questions were followed by specific questions based on the draft category definitions and statements and focused on issues that had generated discussion among the authors, including the FNAB diagnosis of ductal carcinoma in situ. CONCLUSION: The survey results strongly supported the development of the IAC Yokohama System and informed subsequent discussions among the authors regarding the final text.

Osteogenesis imperfecta type I: The role of deep phenotyping in a patient with a ruptured uterus.

As molecular diagnosis of Osteogenesis Imperfecta has become more accessible, there is an increasing ability to consider additional techniques to undertake deep phenotyping of the patient. In this report, we present the details of a female patient with type I Osteogenesis Imperfecta caused due to a pathogenic COL1A1 variant, who suffered from uterine rupture during labour in her second pregnancy, at age 33. Her presentation, patient journey, and histological results are described. Collagen flowers were identified with electron microscopy of a skin biopsy, and the significance of these are explored. Two other recorded cases of women with Osteogenesis Imperfecta who developed uterine rupture are discussed. This report demonstrates the potential role for ultrastructural tissue examination and deep phenotyping, to allow further insights into the relationship between genotype and phenotype.

Histopathological imaging features- versus molecular measurements-based cancer prognosis modeling.

For lung and many other cancers, prognosis is essentially important, and extensive modeling has been carried out. Cancer is a genetic disease. In the past 2 decades, diverse molecular data (such as gene expressions and DNA mutations) have been analyzed in prognosis modeling. More recently, histopathological imaging data, which is a "byproduct" of biopsy, has been suggested as informative for prognosis. In this article, with the TCGA LUAD and LUSC data, we examine and directly compare modeling lung cancer overall survival using gene expressions versus histopathological imaging features. High-dimensional penalization methods are adopted for estimation and variable selection. Our findings include that gene expressions have slightly better prognostic performance, and that most of the gene expressions are weakly correlated imaging features. This study may provide additional insight into utilizing the two types of important data in cancer prognosis modeling and into lung cancer overall survival.

Building a smart FNA cart: When Google meets cytology.

BACKGROUND: The appropriate management of a fine needle aspiration (FNA) supply cart and equipment set up is essential to ensure the smooth and optimal operation of a busy FNA clinic. We applied Lean strategies such as value stream mapping (VSM), the 5S method (Sort, Set in order, Shine, Standardize, Sustain), and Kanban to remove waste and improve patient flow in an FNA clinic. METHODS: The workflow analysis suggested that existent problems such as suboptimal inventory management and unavailability of standard operating procedures (SOPs) caused a 10% to 85% increase in total procedure time. To improve inventory management, we created a 2-bin Kanban system. We used the "Scan to Web" app and a Google Drive form to create a cost-effective electronic inventory management system. We distributed the essential SOPs in the format of video clips using our YouTube channel and leveraged barcode technology to access the links. RESULTS: Upon completion of our process improvement project, we succeeded to eliminate the stock-out events and maintain a process cycle efficiency of 87%. The 5S audit checklist result increased from 6% to 100% implementation, which is consistent with focused improvement. The developed inventory system enabled us to track the supply usage, forecast demands, and improve the accuracy of orders. CONCLUSIONS: Lean methods such as VSM, 5S, and Kanban combined with open source technologies can be implemented to ensure material availability, track inventory, and provide immediate access to SOPs on demand. The developed system also led to increased efficiency and improved flow, as well as responsiveness to changes in demand.

Exploring the Inter-observer Agreement Among the Members of the Italian Consensus for the Classification and Reporting of Thyroid Cytology.

Classification schemes for reporting thyroid cytology of fine needle aspiration (FNA) of thyroid nodules are largely used in clinical practice, but the level of inter-observer agreement among cytopathologists is poorly acknowledged. The present study aimed to explore the inter-observer agreement among the experienced authors of the 2014 Italian Consensus for Classification and Reporting of Thyroid Cytology (ICCRTC). A stratified randomization was performed in order to obtain a sample homogeneously distributed and representative of all ICCRTC classes. Four high-experience raters were randomly selected among the extensors of the Italian consensus. They independently reviewed 60 FNA samples blindly of the initial cytological report and clinical features. Their overall agreement was evaluated according to Fleiss' kappa. The overall inter-observer agreement was moderate (κ 0.46). Specifically, a good agreement was found when the samples were consistent for malignancy (TIR5) or were not adequate for diagnosis (TIR1) (κ 0.67 and κ 0.73, respectively). A moderate agreement was present for suspicious-for-malignant category (TIR4), and a fair agreement was recorded in the two intermediate ones (TIR3A and TIR3B) (κ 0.36 and κ 0.35, respectively). For clinical purposes, the agreement was good (κ 0.74) in differentiating cases with surgical indication (TIR4/TIR5) from those in which surgery is not essential or requires limited extension (TIR3B/TIR3A/TIR2). In conclusion, the present study confirms the reliability of ICCRTC. These data represent a reference for cytopathologists using this system and are useful for the practice of clinicians and surgeons.

A Bethesda-like system for breast cytopathology: A retrospective assessment two decades on.

Fine-needle aspiration biopsy (FNAB) has been used for many decades in the investigation of breast lesions. Originally, cases were signed out using the categories benign and malignant. The benign category contained specimens showing fibrocystic change as well as benign neoplasms such as fibroadenoma. The malignant category contained carcinomas, lymphomas, and phyllodes tumors with specific diagnoses often given in place of the term malignant. Categorization was less clear when the cytopathologists could not definitively separate benign from malignant. This led to the use of terms, such as atypical, suspicious for malignancy, and atypical suspicious with variable definitions and utilization among cytopathologists. In 1997, a uniform approach to breast FNAB was proposed with well-defined diagnostic categories and criteria. This system foreshadowed the recent International Academy of Cytology Standardized Reporting System for Breast Fine-Needle Aspiration Biopsy. These two systems are compared and contrasted.

The international system for reporting serous fluid cytopathology-diagnostic categories and clinical management.

INTRODUCTION: Effusions can develop inside serous cavities in several pathologic states, both neoplastic and non-neoplastic. They are easy to drain and can provide useful diagnostic information. However, the reported diagnostic efficacy of these specimens has not been uniform across different laboratories. To standardize practices, the international system for reporting serous fluid cytology (TIS) was developed in accordance with the best international practices, the most up-to-date reported data, and expert consensus. RESULTS: TIS has set the basic principles for laboratory handling of serous effusion specimens, defined the adequacy criteria, and set a standardized reporting terminology with well-defined criteria for each diagnostic category. These include nondiagnostic, negative for malignancy, atypia of undetermined significance, suspicious for malignancy, and malignant. Each can provide useful inherent information for appropriate clinical management and follow-up, with a defined expected diagnostic category incidence and risk of malignancy. CONCLUSIONS: TIS applies to serous fluids collected from the pleura, peritoneal, and pericardial cavities. Using TIS, indeterminate categories are presented as either preliminary or as options of last resource. TIS has emphasized the role of ancillary tests in arriving at the correct interpretation within each category. It also has emphasized the importance of a malignant diagnosis as a definitive diagnosis, comparable to histologic examinations. Because of the well-documented outcomes in the adoption of uniform cytology terminology for other organ systems, we recommend the use of the upcoming TIS and believe its use will be paramount to improving the diagnostic yield in this area of cytology.

Improving performance of recently introduced flow cytometry-based approach of malignant cell screening in serous cavity effusion.

INTRODUCTION: Microscopy has been recognized as the "gold-standard" cellular analysis of serous cavity effusion. However, this method is time-consuming, labor-intensive, and requires accomplished skills. Here, we investigated the efficiency of hematology analyzer in screening malignant cells in serous cavity effusion. METHODS: A total of 991 serous cavity effusion samples and 370 validation specimens collected from different departments were sent to the clinical laboratory for routine cell count using the automated hematology body fluid (BF) mode and exfoliative cytology simultaneously. High-fluorescent cells (HFCs) were measured as the relative count (HF%) and absolute count (HF#) by BF mode. Receiver operating characteristic curve analysis was combined with scattergram rules to screen malignant cells. RESULTS: HF# and HF% in malignant samples (subgroup) were significantly higher than those in benign samples, and the HF# and HF% levels were different between ascites and pleural effusion (PE). The area under the curve values were also different between ascites and PE. Positive of malignant cells was very high when the ascites or PE sample touching Rule 1 positive and either Rule 2 negative or positive. The cutoff levels of HF# were 5.5 HFC/µL on the basis of Rules 1 and 2 negative, whereas 83.5 HFC/µL on the basis of Rule 1 negative but Rule 2 positive in ascites. By contrast, the cutoff levels of HF% were 0.55 HFC/100 WBC on the basis of Rules 1 and 2 negative, whereas 4.95 HFC/100 WBC on the basis of Rule 1 negative but Rule 2 positive in PE. CONCLUSIONS: Serous cavity effusion will be increasingly analyzed using the automated hematology analyzer BF mode in the future because of its rapidness and convenience. The combined application of HFC with scattergram rules is a feasible and useful approach to screen malignant cells in serous cavity effusion.

Interobserver variability between cytopathologists and cytotechnologists upon application and characterization of the indeterminate category in the Milan System for Reporting Salivary Gland Cytopathology.

BACKGROUND: The indeterminate categories in the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) are diagnostically challenging because of inherent heterogeneity and complexity, with wide interobserver variability (IOV). Herein, the authors explore the concordance rate (CR) between cytopathologists (CPs) and cytotechnologists (CTs) in interpreting indeterminate salivary gland lesions using the MSRSGC. METHODS: Between 2011 and 2016, 86 indeterminate fine-needle aspirations had slides available for review, of which 48 had follow-up. Four CPs and 2 CTs performed an independent, blinded review of these slides and categorized them according to the MSRSGC. The CRs between CTs and CPs with the final sign-out cytopathologist (FCP) were assessed, and interobserver agreement was categorized into uniform, majority, divided, minimal, or no agreement. RESULTS: The overall CR with the FCP ranged from 48.8% to 60.5% for CPs and from 22.1% to 36% for CTs. IOV κ scores for the entire group were 0.314 and, with the FCP as the reference, ranged from 0.403 to 0.539 for CPs and from 0.091 to 0.254 for CTs. Uniform, majority, divided, minimal, and no agreement was noted in 12.8%, 31.4%, 38.4%, 10.5%, and 6.9%, respectively, of all cases and in 16.7%, 35.4%, 31.3%, 8.3%, and 6.3%, respectively, of the cases with follow-up. Diagnostic challenges included distinguishing lymphoma from a reactive process and distinguishing mucin from mucin-like material. CONCLUSIONS: CPs had modestly higher CRs compared with CTs; and, although the variable CRs highlight indeterminate IOV, the MSRSGC enables reproducibility. Characterizing larger cohorts in the indeterminate categories will further improve MSRSGC criteria. Moreover, education on the MSRSGC should include CTs and CPs to improve overall diagnostic accuracy.

Application of the International System for Reporting Serous Fluid Cytopathology (ISRSFC) on Reporting Pericardial Effusion Cytology.

INTRODUCTION: The International System for Reporting Serous Fluid Cytopathology (ISRSFC) has recently been announced. Pericardial effusion (PE) is a clinical manifestation of a large variety of both neoplastic and non-neoplastic conditions. Herein, we have applied the ISRSFC on reporting PE cytopathology and report our experience in a large academic institution. METHOD AND MATERIALS: After the Institutional Research Board approval, the electronic pathology database of a large academic institution was queried for PEs collected from January 2014 to January 2019. The diagnosis, patient demographics, and specimen volume were recorded for each case. The ISRSFC was applied and the cases were divided into 5 categories: nondiagnostic (ND), negative for malignancy (NFM), atypia of uncertain significance (AUS), suspicious for malignancy (SFM), and malignant (MAL). Each category was evaluated separately. RESULTS: A total of 299 cases were identified, 162 females and 137 males. The age of the subjects ranged from less than a year to 89 years (average 51.25 years). The volume ranged from 3 to 1,700 mL (average 298 mL). There were 252 NFM (84.3%), 13 AUS (4.3%), 4 SFM (1.3%), and 30 MAL (10%) cases. Metastatic lung cancer followed by metastatic breast cancer were the most common malignancies involving pericardial fluid (PF). No cases were diagnosed as ND. However, no mesothelial cells were seen in 97 specimens (38% of the negative cases). None of these patients developed malignant PE in at least 6 months of follow-up. CONCLUSION: The ISRSFC is a user-friendly reporting system which is easily applicable on serous fluid including PF. The vast majority of PEs was benign (84.3%). Our study shows that the presence of mesothelial cells is not necessary for specimen adequacy in serous effusions as no mesothelial cells were identified in 38% of the negative cases. Metastatic lung carcinoma was the most common diagnosis of malignant effusions.

Evolution of guidelines for respiratory cytology by the Papanicolaou Society of Cytopathology.

Cytology serves a fundamental role in the evaluation of the lower respiratory tract. Cytological specimens are often the first diagnostic attempt for the evaluation of radiographic alterations. The categorization of the pathological process as infectious, inflammatory or neoplastic is critical in guiding further clinical management of the affected patient. Therefore it is imperative that cytopathologists use a standardized approach to sample handling and reporting in order to establish clear communication with the treating physician. The Papanicolaou Society of cytopathology has been an active leader in this field and has proposed several guidelines for sampling, handling, and reporting of lower respiratory tract cytology. These guidelines have been updated to incorporate new emerging concepts and technologies in the field. Respiratory medicine is a fast growing area with constant new challenges, thus requiring an ever demanding adaptation from cytopathologists and cytology specific guidelines.