Cell blocks in urine cytopathology: do they add value to the diagnosis? A pilot study

INTRODUCTION

The utility of cell block (CB) preparation is well established in cytopathology. Despite 23.3% of College of American Pathologists-accredited laboratories using CB with liquid-based preparations on urine cytology (UC) cases, there are very few studies on their performance. To determine their usefulness, we conducted a retrospective review of UC cases that received CB.

MATERIALS AND METHODS

We identified 27 UC cases with ThinPrep (TP) and CB preparation between 2016 and 2020 at our institution. Clinical history and follow-up data were compiled. A blinded review of TP alone, and TP together with CB, was performed by 2 pathologists and 2 cytotechnologists. Diagnoses were rendered in accordance with The Paris System for Reporting Urine Cytology.

RESULTS

Blood and acute inflammation were common background elements in cases that received CB preparation. In total, CB upgraded the diagnosis in 7 of 27 cases (26%). The maximum utility of CB preparation was seen in indeterminate cases where 60% (6 of 10) were upgraded, including 71% (5 of 7) of atypical urothelial cells (AUC) and 30% (1 of 3) of suspicious for high-grade urothelial carcinoma (HGUC). One case (1 of 12, 8%) diagnosed as negative for HGUC on TP was diagnosed as low-grade urothelial neoplasia on CB.

CONCLUSIONS

Our results demonstrate that adjunct use of CB preparation aids in a definitive diagnosis on AUC category and may be helpful in cases with cell clusters or tissue fragments, or cases suspicious for HGUC. Further correlation studies are warranted in this area to expand our knowledge about the utility of CBs in urine cytology.

Application of Milan system for reporting of salivary gland pathology and risk stratification: An institutional experience

Background:

Fine-needle aspiration cytology (FNAC) is a sensitive technique for diagnosing salivary gland pathologies. Milan system of reporting salivary gland cytopathology (MSRSGC) is an evidence-based system of reporting which has been introduced to improve reporting and communication between cytopathologist and clinician by introducing standardized categories with specified treatment protocols.

Aims and Objectives:

The aim of the present study is to find the diagnostic accuracy and risk of malignancy (ROM) in various categories when MSRSGC is applied.

Materials and Methods:

A single-institute-based 3-year retrospective study was done. All salivary gland lesions were reclassified according to MSRSGC. ROM, diagnostic specificity, sensitivity and accuracy of FNAC of salivary gland lesions were calculated.

Results:

A total of 133 cases were included in the study. Overall, the most common diagnosis was found to be pleomorphic adenoma comprising 61 (42.8%) of all cases. Adenoid cystic carcinoma was the most commonly diagnosed malignancy comprising of 6 (4.5%) of all lesions. Cases were further divided into Milan categories, namely nondiagnostic, nonneoplastic, atypia of undetermined significance, benign neoplasm, neoplasm of undetermined malignant potential, suspicious of malignancy and malignancy comprising 5 (3.7%), 29 (21.8%), 77 (57.8%), 4 (3%), 3 (2.2%), 1 (0.7%) and 14 (10.5%) cases, respectively, with ROM of 0, 14.28%, 33.33%, 5.71%, 66.66%, 100% and 80%, respectively. Sensitivity, specificity and diagnostic accuracy to separate benign from malignant lesions were 80%, 89.80% and 87.50%, respectively.

Conclusion:

FNAC of the salivary gland lesions is a safe and reliable diagnostic procedure. The Milan system of reporting is a risk stratification system which can improve the overall effectiveness of reporting and care of patients.

Papanicolaou Staining and Processing Troubleshooting Exercise Using Digital Pathology: Peer Comparison in an External Quality Assurance Setting

BACKGROUND

The Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) offers a comprehensive range of External Quality Assurance programs for all disciplines of pathology and is committed to delivering programs to advance outcomes in patient care and promote excellence in laboratory diagnostic and technical proficiency. Proficiency testing in cytopreparatory techniques became available for formal enrolment in 2018. The 2019 technical program focused on the demonstration of a laboratory to troubleshoot problems encountered during staining and processing. The exercise provided a peer comparison of a laboratory's ability to (1) identify the problem viewed from a digital image and (2) describe the troubleshooting steps to rectify the problem using assessment guidelines.

METHODS

Ten troubleshooting exercises including whole-slide z-stacked virtual images, a reference slide, and an online Result Entry questionnaire were provided. Common staining and processing problems were demonstrated in these exercises. Multiple-choice responses were made available to participants for each case with 1 response requiring submission. Participants were then allowed free text to describe how they would rectify the problem.

RESULTS

Of the 72 participants who participated, 62 participants (86%) achieved a satisfactory assessment, 6 participants (8%) received a borderline assessment, and 4 participants (6%) received an unsatisfactory assessment. The average mark obtained was 32.7 out of a total of 45 marks, which equates to a satisfactory assessment. The highest mark obtained for this survey was 42.5.

CONCLUSIONS

Quality cytopathology preparatory techniques are integral to mitigating the risk of diagnostic error. The digital pathology platform allowed homogeneity of samples for all participants and appeared to be a satisfactory mode for demonstrating the technical problems to participants. Laboratories participating in this survey showed good performance in identifying processing and staining problems on virtual images and working through the troubleshooting steps. The exercise also identified a method for troubleshooting formalin vapour-affected slides using citrate buffer which may be useful for laboratories following in-house validation.

Improved diagnostic yield of endoscopic ultrasound-fine needle biopsy with histology specimen processing

BACKGROUND

Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) has emerged as a safe, efficacious alternative to fine needle aspiration (FNA) for tissue acquisition. EUS-FNB is reported to have higher diagnostic yield while preserving specimen tissue architecture. However, data on the optimal method of EUS-FNB specimen processing is limited.

AIM

To evaluate EUS-FNB with specimen processing as histology vs EUS-FNA cytology with regards to diagnostic yield and specimen adequacy.

METHODS

All EUS-FNA and EUS-FNB performed at our institution from July 1, 2016, to January 31, 2018, were retrospectively analyzed. We collected data on demographics, EUS findings, pathology, clinical outcomes, and procedural complications in two periods, July 2016 through March 2017, and April 2017 through January 2018, with predominant use of FNB in the second data collection time period. FNA specimens were processed as cytology with cell block technique and reviewed by a cytopathologist; FNB specimens were fixed in formalin, processed for histopathologic analysis and immunohistochemical staining, and reviewed by an anatomic pathologist. Final diagnosis was based on surgical pathology when available, repeat biopsy or imaging, and length of clinical follow up.

RESULTS

One hundred six EUS-FNA and EUS-FNB procedures were performed. FNA alone was performed in 17 patients; in 56 patients, FNB alone was done; and in 33 patients, both FNA and FNB were performed. For all indications, diagnostic yield was 47.1% (8/17) in FNA alone cases, 85.7% (48/56) in FNB alone cases, and 84.8% (28/33) in cases where both FNA and FNB were performed (P = 0.0039). Specimens were adequate for pathologic evaluation in 52.9% (9/17) of FNA alone cases, in 89.3% (50/56) of FNB alone cases, and 84.8% (28/33) in cases where FNA with FNB were performed (P = 0.0049). Tissue could not be aspirated for cytology in 10.0% (5/50) of cases where FNA was done, while in 3.4% (3/89) of FNB cases, tissue could not be obtained for histology. In patients who underwent FNA with FNB, there was a statistically significant difference in both specimen adequacy (P = 0.0455) and diagnostic yield (P = 0.0455) between the FNA and FNB specimens (processed correspondingly as cytology or histology).

CONCLUSION

EUS-FNB has a higher diagnostic yield and specimen adequacy than EUS-FNA. In our experience, specimen processing as histology may have contributed to the overall increased diagnostic yield of EUS-FNB.

Cytomorphologic characteristics of next-generation sequencing-positive bile duct brushing specimens

INTRODUCTION

Cytology of bile duct brushings (BDBs) is a specific, but insensitive, test for malignancy. Next-generation sequencing (NGS) of BDBs has recently been shown to improve sensitivity. We analyzed the cytologic features of NGS-positive (NGS⁺) and NGS-negative (NGS^-) BDBs and correlated the morphology with the presence of mutations.

MATERIALS AND METHODS

A total of 96 BDBs were analyzed for 29 cytologic features by 2 pathologists who were unaware of the original diagnosis and NGS results. Clinicopathologic follow-up was used to determine the patient outcomes (ie, benign, low-grade neoplasm, malignant [carcinoma/high-grade dysplasia]).

RESULTS

We analyzed 74 NGS⁺ BDBs from 66 patients and 22 NGS^- BDBs from 22 patients. During follow-up, 58 of 66 NGS⁺ patients (88%) had malignancy compared with 0% of NGS^- patients (P < 0.001). Fewer than 50% of the malignant cases had been interpreted as malignant on cytology; however, 100% had demonstrated mutations using NGS. Within the NGS⁺ cases, 53% showed late mutations (TP53, SMAD4, and CDKN2A) supportive of a high-risk stricture. Significant morphologic differences were seen in the background appearance, presence of single cells, architectural disarray, nucleomegaly, anisonucleosis, irregular nuclear borders, increased nuclear/cytoplasmic ratio, nuclear hyperchromasia, nucleoli, abnormal groups, clusters, and/or single cells, and overall impression. Naked nuclei, nucleomegaly, anisonucleosis, and coarse chromatin were more common in BDBs with late mutations than in those with KRAS/GNAS (Kirsten rat sarcoma viral oncogene homolog/guanine nucleotide binding protein, α-stimulating complex locus) mutations only. Cytology had a sensitivity of 16% and a specificity of 100% for malignancy. In contrast, NGS had a sensitivity of 100% and a specificity of 73%. Late mutations were 100% specific for malignancy compared with mutations in KRAS/GNAS only, of which 69% were malignant.

CONCLUSIONS

We found significant overlap in the cytomorphologic features between neoplastic and non-neoplastic BDBs, and more than one half of cancer cases had been interpreted as "nonmalignant" on cytology. NGS showing late mutations was 100% specific for malignancy. Adding genetic testing to BDB cytology would be a valuable ancillary test for the detection of malignancy, and reflex testing should be considered.

Musculoskeletal small biopsies from small patients: current status in 2 academic hospitals

INTRODUCTION

Pediatric bone and soft tissue (BST) lesions typically undergo biopsy prior to treatment, which commonly involves core needle biopsy (CNB) and/or fine-needle aspiration biopsy (FNAB). This study looks at the utility of small biopsies in the current diagnosis of pediatric BST lesions from 2 institutions.

MATERIALS AND METHODS

A retrospective search of BST small biopsies obtained during a 2-year time period (2018-2019) at 2 academic institutions was performed to look at clinicopathologic features, biopsy diagnoses, and correlation with follow-up.

RESULTS

A total of 96 pediatric patients (average age 11.2 years, range: 10 months-19 years) with BST lesions underwent a small biopsy, which represents 5% of the total BST lesions biopsied. The results show that the majority of lesions were benign (65%), and diagnosed by CNB alone (73%); a combination of FNAB and CNB (16%), and FNAB alone (11%), were less frequent. The CNB was effective in making a definitive diagnosis in 93% of cases and overall small biopsy was effective in 91% of the cases. Cases with definitive diagnoses on small biopsy were more likely to have concurrent CNB or characteristic ancillary studies performed.

CONCLUSIONS

Although pediatric BST lesions constitute only 5% of all BST lesions biopsied, minimally invasive small biopsies with cytologic evaluation for triage and appropriate ancillary study utilization can help render specific diagnoses that help to determine the appropriate treatment for young patients with BST lesions. The current diagnostic approach frequently involves CNB with intraprocedural evaluation or concurrent FNAB, with fewer biopsied by FNAB alone.

Primary Synovial Sarcoma of the Thyroid: Challenges in Cytologic Diagnosis and Review of the Literature

BACKGROUND

Primary synovial sarcoma (SS) of the thyroid (PSST) is extremely rare. Its differential diagnosis from other neoplasms is essential since it has different management protocols and prognosis.

CASE

A 26-year-old man with a 4.5-cm solid lobulated mass was seen at an outside hospital. Fine needle aspiration (FNA) was interpreted as a papillary carcinoma, and a total thyroidectomy was performed. The final histologic diagnosis was spindle epithelial tumor with thymus-like differentiation (SETTLE). No metastases were detected at that time, and the patient received radioactive iodine treatment. Two years post-surgery, he was seen at our hospital with a local recurrence, and FNA was considered as consistent with SETTLE. The mass was resected, and a left modified radical neck dissection was performed. The tumor revealed necrosis and a high mitotic index. Following histologic, immunohistochemical, and molecular studies, the tumor was classified as a PSST. The patient received chemotherapy and targeted immunotherapy, but he died 41 months after the initial presentation.

CONCLUSION

The main diagnostic pitfall of PSST is SETTLE. The presence of mitotic figures and basal lamina material, negative staining for smooth muscle actin, and positive staining for transducer-like enhancer of split 1 antibody favor SS over SETTLE. SYT gene rearrangement is essential to establish the definitive diagnosis of PSST.

Fine needle aspiration of thymic epithelial neoplasms and non-neoplastic lesions

Thymic epithelial neoplasms are rare as these tumors represent less than 1% of all human tumors. In addition, thymic hyperplasia and thymic cysts can also present as anterior or less often superior mediastinal masses. Fine needle aspirates and core biopsies of thymic epithelial neoplasms are rarely encountered in routine pathology practices. Histologic classification of these lesions requires microscopic examination of the entire lesion as a significant number of tumors can have more than one histologic type and the status of invasion into adjacent soft tissues or organs is needed for accurate staging. Therefore, it is important to understand the limitations of the information these biopsy methods can provide. The accuracy of the diagnosis can be improved by using ancillary techniques like immunohistochemistry and flow cytometry. In this review, we are summarizing the clinical, histologic and cytologic characteristics of thymic cysts, thymic hyperplasia and thymic epithelial neoplasms including different types of thymoma and thymic carcinoma.

Primary pancreatic Ewing sarcoma: a cytomorphologic and histopathologic study of 13 cases

INTRODUCTION

Ewing sarcoma (ES) is a small, round cell sarcoma that rarely occurs in solid organs, including the pancreas. A diagnostic overlap exists with other primary pancreatic neoplasms, especially for specimens from small biopsies and fine needle aspiration (FNA). To improve the diagnosis of this rare pancreatic tumor, we have reported a series of 13 cases of primary pancreatic ES and reviewed the cytopathologic, surgical pathology, clinical, and radiologic features of these neoplasms.

MATERIALS AND METHODS

We performed a retrospective case review of 13 patients with a diagnosis of pancreatic ES from 2 tertiary academic medical centers. A combination of cytology and histopathologic slides were reviewed, and the patient demographics, clinical information, somatic genetics, and radiologic findings were obtained from the electronic medical records.

RESULTS

Five FNA specimens from 5 patients and 8 surgical biopsy or resection specimens were identified and reviewed. The patients included 9 males and 4 females, with a median age of 27 years (range, 15-78 years). The cytology smears were highly cellular and showed a combination of complex tissue fragments and singly dispersed small round blue cells. The final diagnosis was ES for all 5 FNA specimens in accordance with the characteristic cytomorphology, diffuse and/or strong membranous immunolabeling for CD99, membranous β-catenin, and molecular confirmation of EWSR1 using fluorescence in situ hybridization or reverse transcriptase polymerase chain reaction.

CONCLUSIONS

The cytologic diagnosis of ES is challenging, especially in unusual locations such as the pancreas. However, the correct cytologic diagnosis is important because these patients will require neoadjuvant therapy before surgery. Confirmatory molecular studies should be required to render the diagnosis of pancreatic ES.

Fine-needle aspiration cytology in the diagnosis of salivary gland lesions. The role of the Milan system for reporting cytopathology

BACKGROUND

Fine needle aspiration cytology (FNAC) is an established technique in the management of salivary gland lesions. The Milan System for reporting salivary gland cytopathology (MSRSGC) intents to standardize diagnostic categories. Current studies are trying to evaluate the diagnostic approach of this system.

METHODS

FNAC of salivary gland lesions were retrieved over an 11-year period. 185 FNAC specimens from 182 patients were reviewed blindly and classified according to the criteria established by the MSRSGC. 136 (74.7%) patients had follow-up of their processes.

RESULTS

The total number of diagnostic categories and risk of malignancy (ROM) in 185 specimens were the following: non-diagnostic 39 (21.1%; ROM 12%), non-neoplastic 35 (18.9%; ROM 0%), atypia of undetermined significance (AUS) 17 (9.2%; ROM 46.1%), benign neoplasm 75 (40.5%; ROM 4.9%), salivary gland neoplasm of uncertain malignant potential 4 (2.2%; ROM 100%), suspicious for malignancy 7 (3.8%; ROM 100%), malignant 8 (4.3%; ROM 100%). No false positives were observed in groups IVb, V, and VI in this series. The overall sensitivity, specificity, negative predictive value, positive predictive value and diagnostic accuracy were 88%, 91.8%, 96.3%, 76.7%, and 91% respectively.

CONCLUSION

The ROM reported in our study was in keeping with ROM published by the MSRSGC. This system provides standardized information for risk stratification. The category AUS encompassed cases causing uncertainty representing a challenge in management. Defining criteria for AUS category need to be refined. The system facilitates communication between pathologists and clinicians favoring improvement in patient care.

Current Topics and Practical Considerations of Cytology Practice in Lung Cancer: Reflexions from the Lung Symposium at the 42nd European Congress of Cytology, Malmö, 2019

In June 2019, a lung symposium was held at the 42nd European Congress of Cytology in Malmö, Sweden. Due to the current importance of cytological samples in the diagnoses and molecular analysis to set up the utmost management of lung cancer patients, cytologists from different countries shared the experience of their institutions. The place of the cytological samples gains more and more importance on the potential long-term survival gain through personalized medicine and this harbors the improvement of the guidelines both in pathology and cytology field. In this symposium, the new 6-tiered reporting system for pulmonary cytology proposed by the Papanicolaou Society of Cytopathology and detailed cytomorphological approach to lung carcinoma including lookalike lesions and DNA- and RNA-based analysis of cytology material have been discussed. The cytopathologist plays a pivotal role in ensuring success of a correct triage for the cytology material to be sure of the adequacy and quality of the yield from the rapid on-site evaluation till the report which should encompass molecular profile in rational patient management.

Cytologic Evaluation of Tumor-Infiltrating Lymphocytes for Adoptive Cell Therapy

OBJECTIVES

Novel immunotherapeutic options for refractory metastatic cancer patients include adoptive cell therapies such as tumor infiltrating lymphocytes (TILs). This study characterizes the clinicopathologic findings in a cohort of TIL specimens.

METHODS

Patients with metastatic malignancy who were eligible had TILs from their metastases grown and expanded and then sent to pathology.

RESULTS

A total of 11 TIL specimens (10 melanoma, 1 adenocarcinoma) from patients enrolled in an experimental clinical trial were reviewed. All specimens showed more than 200 lymphoid cells, stained positive for lymphoid markers confirming an activated cytotoxic T-cell immunophenotype, and morphologically showed an intermediate-sized population with immature chromatin and frequent mitoses. Six cases (55%) showed large cells with nucleomegaly and prominent nucleoli.

CONCLUSIONS

This report is the first describing cytopathologic findings of autologous TIL therapy including adequacy guidelines and expected cytomorphologic and immunophenotypic findings. To meet this novel clinical demand, a predefined cytology protocol to rapidly process and interpret these specimens needs to be established.

Cytopathology and immune response in the hepatopancreas of decapod crustaceans

The hepatopancreas of decapod crustaceans is used as an example to illustrate the range of cytopathologies, detoxification mechanisms, and immune responses that environmental toxicants and pathogens can induce in a single organ. The hepatopancreas is the central metabolic organ of decapods and consists of hundreds of blindly-ending tubules and intertubular spaces. The tubular epithelium contains 5 structurally and functionally different cell types, and the interstitium contains haemolymph, haemocytes, connective tissue, and fixed phagocytes. Some physiological conditions such as moulting and starvation cause marked but reversible ultrastructural alterations of the epithelial cells. Environmental toxicants induce either detoxification mechanisms or structural damage in cells, depending on toxicant and concentration. The hepatopancreas is also a main target organ for pathogens, mainly viruses, bacteria, and protists that enter the body via the digestive tract and gills and replicate in the hepatopancreatocytes. The cytopathologies caused by toxicants and pathogens affect single cell types specifically or, more often, several cell types simultaneously. Pathogenesis often begins in a certain cell organelle such as the nucleus, mitochondrion, or endoplasmic reticulum, spreads to other organelles, and ends with death of the infected cell. Fixed phagocytes in the interstitium capture and degrade pathogens that move from the infected tubules into the intertubular spaces or enter the hepatopancreas via circulation. Relatively few disease agents elicit the melanisation and encapsulation reaction that encloses infected tubules by a rigid melanised capsule and kills the entrapped pathogens.

Smartphone-Assisted Telecytopathology: An Intraobserver Concordance Study

INTRODUCTION

Telecytology is the practice of cytology at a distance. The images captured by a camera are sent to the cytopathologist at a different location who views the images and reaches a diagnosis. Recently, smartphone-assisted telepathology has been evaluated for different subspecialities of pathology including cytology for second opinion.

MATERIALS AND METHODS

For the purpose of the study, a total of 151 cases of fine needle aspiration and 10 cases of urine cytology reported by a single pathologist were retrieved from the records. The images of all the cases were captured by a trained pathologist using the primary camera of a smartphone from the ocular of a binocular microscope. The images were sent by WhatsApp to the same pathologist who had made the conventional microscopy diagnosis. The images were viewed on the smartphone screen by the pathologist who replied with the diagnosis after analysing all the images with or without digital zoom.

RESULTS

A total of 154 cases out of 161 were correctly diagnosed on smartphone-assisted telepathology (overall intraobserver concordance of 95.6%). For head and neck swellings, the concordance was 65/70 (92.9%), for breast lesions, it was 23/24 (95.8%), and for miscellaneous swellings, it was 57/57 (100%). For urine cytology, the concordance rate was 9/10 (90%).

CONCLUSION

Though the results of this study are encouraging, further improvement in the smartphone camera resolution and internet connectivity would enhance the utility of smartphone-assisted telecytopathology.

Breast fine needle aspiration biopsy cytology: the potential impact of the International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology and the use of rapid on-site evaluation

The present report reviews the current problems associated with the routine use of breast fine needle aspiration biopsy (FNAB) and discusses the potential impact that the new International Academy of Cytology (IAC) Yokohama Reporting System and the use of rapid on-site evaluation (ROSE) should have on reducing these problems to optimize breast care for patients. The recently reported IAC System aims to establish the best practice guidelines for breast FNAB, emphasizing the importance of the FNAB technique and the skillful preparation of direct smears. The IAC System proposes a standardized report and established clear terminology for defined reporting categories, each of which has a risk of malignancy and is linked to management options. The FNAB techniques that will optimize the biopsy specimen and reduce poor quality smears are reviewed and the benefits of ROSE are discussed. FNAB can diagnose accurately the vast majority of breast lesions, and ROSE has been recommended whenever possible to reduce the rate of insufficient/inadequate cases and increase the number of specific benign and malignant diagnoses. ROSE performed by a cytopathologist provides a provisional diagnosis, reducing patient anxiety and facilitating management through cost-effective immediate triage and patient selection for ancillary testing. Thus, patients can be selected for immediate core needle biopsy, as required.

[Salivary gland cytopathology: Milan system 2018]

The salivary glands cytology is one of the most challenging area in cytopathology because of the wide diversity of benign and malignant tumors also because of their heterogeneity. However, fine needle aspiration cytology, with magnetic resonance imaging, represents a first-line examination to guide a possible surgical procedure and its extent. An accurate diagnosis of a specific tumor is sometimes difficult to assess in cytology. Also, as for gynecological, thyroid or urinary cytologies, a panel of experts met to develop a cytological classification of salivary gland lesions associated with a risk of malignancy and management proposals. The Milan System for Reporting Salivary Gland Cytopathology was published in 2018. The French Society of Clinical Cytology (SFCC) offers here an official summarized French version oh this terminology and recommends its use.

British Journal of Biomedical Science in 2019. What have we learned?

In 2019 the British Journal of Biomedical Science published 40 articles in the various disciplines that comprise biomedical science. These were one review, 22 original articles and 17 'In Brief' short reports. Of those citing original data, the majority were in cellular pathology (14 papers), clinical chemistry (9 papers), and microbiology (6 papers: 4 in bacteriology and 2 in virology). There were 3 papers in haematology and 2 in andrology, whilst 5 papers crossed traditional discipline boundaries (such as the molecular genetics of IL6, liver function tests, and hepatocellular carcinoma). Over two-thirds of papers used techniques in molecular genetics. The present report will summarise key aspects of these publications that are of greatest relevance to laboratory scientists.

Variants of Papillary Thyroid Carcinoma: An Algorithmic Cytomorphology-Based Approach to Cytology Specimens

BACKGROUND

Thyroid cancer accounts for 1% of cancer cases in developed countries, in which papillary thyroid carcinoma (PTC) is the most common type. There are multiple variants of PTC described to date, some of them with aggressive behavior and poor clinical outcome. These variants are well described and accepted in recent guidelines of many international societies, and the prognostic and management implications are well laid out. Due to their established clinical importance and to guide appropriate surgical management, it is now imperative in clinical practice, including cytopathology, to differentiate aggressive variants from nonaggressive ones. This review aims to describe the variants of PTC and to provide a practical algorithmic approach to facilitate the cytological diagnosis of these variants.

SUMMARY

Subtyping PTC variants on fine needle aspiration cytology (FNAC) is challenging even for the most experienced cytopathologist. To facilitate a correct subtyping on FNAC, we propose a stepwise approach that is mainly designed for conventional smear methodology. This approach requires first to stratify the lesions into oncocytic and nononcocytic features before analyzing further details in cell morphology and pattern. Key Messages: (1) Subtyping in PTC is possible on cytopathology. (2) The main aim of the cytopathologist is to differentiate aggressive from nonaggressive variants. (3) The subtyping of PTC can help in the surgical management of the patients.

The histopathological, cytopathological and ultrastructural effects of carbaryl on gills of Oreochromis niloticus (Linnaeus, 1758)

Ultrastructural and histopathological reponses in the organs of living organisms are important and useful tools to determine the health condition and the effects of pollutants, such as pesticides, on the organisms. The aim of this study is to determine possible histopathological, cytopathological and ultrastructural alterations in gills of Oreochromis niloticus individuals exposed to 850 μg/L carbaryl standart at 7th, 14th and 21st days with light and electron microscopes. The fish were exposed to carbaryl for 21 days and the histopatological, ultrastructural and cytopathological alterations occuring in the gill tissues of organisms were determined by light, Scanning and Transmission Electron Microscopes (SEM and TEM). At the end of the study, it was observed that carbaryl caused both histopathological and cytopathological changes in the gills of O. niloticus. It has been determined that the most of the pathological changes in the exposed organisms are the metabolic defence reactions.

Identification of infectious organisms in cytopathology: A review of ancillary diagnostic techniques

Cytology samples obtained from exfoliative sources and fine-needle aspiration (FNA) procedures can all be used to detect microorganisms and/or the associated cytopathologic effects (CPE) caused by an infection. There are many advantages to utilizing cytology samples as an adjunct to routine microbiology laboratory methods. For example, cytology samples can be obtained by non-invasive and minimally invasive techniques, and interpretation is affordable, accurate, and fast. Furthermore, routine cytology stains, including the Papanicolaou (Pap) and the Diff-Quik (DQ) stains, can adequately identify a number of microorganisms. Finally, material obtained by these procedures can also be used for cytologic ancillary testing, microbiology culture, and molecular studies. Currently, there are a variety of ancillary diagnostic techniques that are routinely utilized in the cytopathology laboratory. Additionally, the increasing utilization of molecular-based, diagnostic techniques on fluid specimens, as well as FFPE material, is expanding the role of cytopathology for infectious disease diagnostics. In this review, we provide an overview of the most practical ancillary techniques commonly used to identify microorganisms on cytology specimens.

Cytopathology and ultrastructure identification of primary hepatic acinar cell carcinoma: Case report

•

Acinar cell carcinoma originating in the liver proper remains a diagnostic quandary.

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Non-specific imaging features may have led to prior misdiagnosis and poor outcomes.

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Ultrastructural electron microscopy represents a novel tool for identification.

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Heterotopia or metaplastic mechanisms may underlie hepatic acinar cell localization.

•

The previous literature is summarized in context of the present case of hepatic ACC.

Introduction

A primary acinar cell carcinoma (ACC) of the liver was incidentally diagnosed in a clinically asymptomatic 80-year-old man. This study aimed to delineate critical diagnostic characteristics of an ACC originating uniquely from the liver to improve its future identification.

Presentation of case

Enhanced MRI revealed a heterogenous, cystic 7.7 × 11.1 × 10.4 cm tumour occupying hepatic segments II and III. The mass demonstrated mild diffuse enhancement in hepatic arterial phase with minimal portal venous washout in a liver without cirrhotic features. A central stellate T2-hyperintense necrotic scar and outer capsule were apparent. No primary lesion or metastasis outside the liver was discernable. Post-left hepatic lobectomy, the tumour immunophenotype was atypical for presumptive diagnoses of hepatocellular carcinoma (HCC) or cholangiocarcinoma. Extensive morphologic workup on electron microscopy definitively diagnosed primary hepatic ACC by establishing presence of secretory zymogen-like granules, intracytoplasmic microvilli and acinar cell differentiation. Cytopathology revealed cellular lumen expressing PAS-positive diastase-resistant granular cytoplasmic contents.

Discussion

This case showcased the novel utility of electron microscopy that was crucial in yielding the definitive diagnosis. The previous literature on hepatic ACC was compiled here in context of the present case. The mechanism of hepatic acinar cell localization was also discussed.

Conclusion

Primary hepatic ACC may easily be confused for other lesions due to nonspecific imaging patterns. Specifically, the presence of a central scar without risk factors for HCC can favour a diagnosis of benign entities such as focal nodular hyperplasia (FNH). Electron microscopy presents an important tool to identify primary hepatic ACC and may improve future patient outcomes.

Assessment of The Bethesda System for Reporting Thyroid Cytopathology

OBJECTIVES

Long-term follow-up is important for determining performance characteristics of thyroid fine-needle aspiration (FNA).

METHODS

Histologic or 3 or more years of clinical follow-up was used to calculate performance characteristics of thyroid FNA before and after implementation of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). The impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) classification was also investigated.

RESULTS

Follow-up was obtained for 1,277/1,134 and 1,616/1,393 aspirates/patients (median clinical follow-up, 9.9 and 4.4 years, pre- and post-TBSRTC, respectively). Nondiagnostic, suspicious for follicular neoplasm, and suspicious for malignancy (SFM) diagnoses decreased and benign diagnoses increased post-TBSRTC, while atypical rate remained less than 1%. Negative predictive value for benign nodules and positive predictive value (PPV) for SFM increased significantly. Eleven nodules were reclassified as NIFTP, slightly decreasing PPV/risk of malignancy (ROM).

CONCLUSIONS

Appropriate ROM for thyroid FNA can be achieved through application of TBSRTC terminology with minimal use of atypical category.

Factors in the disease severity of ATP1A3 mutations: Impairment, misfolding, and allele competition

Dominant mutations of ATP1A3, a neuronal Na,K-ATPase α subunit isoform, cause neurological disorders with an exceptionally wide range of severity. Several new mutations and their phenotypes are reported here (p.Asp366His, p.Asp742Tyr, p.Asp743His, p.Leu924Pro, and a VUS, p.Arg463Cys). Mutations associated with mild or severe phenotypes [rapid-onset dystonia-parkinsonism (RDP), alternating hemiplegia of childhood (AHC), or early infantile epileptic encephalopathy (EIEE)] were expressed in HEK-293 cells. Paradoxically, the severity of human symptoms did not correlate with whether there was enough residual activity to support cell survival. We hypothesized that distinct cellular consequences may result not only from pump inactivation but also from protein misfolding. Biosynthesis was investigated in four tetracycline-inducible isogenic cell lines representing different human phenotypes. Two cell biological complications were found. First, there was impaired trafficking of αβ complex to Golgi apparatus and plasma membrane, as well as changes in cell morphology, for two mutations that produced microcephaly or regions of brain atrophy in patients. Second, there was competition between exogenous mutant ATP1A3 (α3) and endogenous ATP1A1 (α1) so that their sum was constant. This predicts that in patients, the ratio of normal to mutant ATP1A3 proteins will vary when misfolding occurs. At the two extremes, the results suggest that a heterozygous mutation that only impairs Na,K-ATPase activity will produce relatively mild disease, while one that activates the unfolded protein response could produce severe disease and may result in death of neurons independently of ion pump inactivation.

Genomic and antigenic characterization of a cytopathic bovine viral diarrhea virus 1i isolated in the United States

Bovine viral diarrhea viruses (BVDV) are a common global viral pathogen of ruminants. Considerable genetic variability is found amongst BVDV1 isolates, with at least 21 subgenotypes being described. In the United States, BVDV1a and 1b are the only subgenotypes described to date. Here, the genomic sequence of CA2005, a cytopathic BVDV1, was determined. This virus, isolated in California, did not segregate into either BVDV1a or 1b subgenotypes. BLAST analysis showed CA2005 was most closely related to BVDV1i isolates. CA2005 was also the first cytopathic BVDV1i and one of few non-1a, non-1b cytopathic viruses reported. The genomic sequence was 15,752 nucleotides in length. Cytopathogenicity was conferred by duplication of the NS3 protein with a small ubiquitin B insertion at the border of the NS2/NS3 proteins. Virus neutralization assays using antisera against BVDV1a vaccine viruses revealed variable neutralization, suggesting modified live vaccines may not be totally protective against CA2005 and similar viruses.