The autonomic nerves around the vein of Marshall: a postmortem study with clinical implications

This study aims to analyze the vein of Marshall (VOM) in human autopsy hearts and its correlation with clinical data to elucidate the morphological substrates of atrial fibrillation (AF) and other cardiac diseases. Twenty-three adult autopsy hearts were studied, assessing autonomic nerves by immunohistochemistry with tyrosine hydroxylase (sympathetic nerves), choline acetyltransferase (parasympathetic nerves), growth-associated protein 43 (neural growth), and S100 (general neural marker) antibodies. Interstitial fibrosis was assessed by Masson trichrome staining. Measurements were conducted via morphometric software. The results were correlated with clinical data. Sympathetic innervation was abundant in all VOM-adjacent regions. Subjects with a history of AF, cardiovascular cause of death, and histologically verified myocardial infarction had increased sympathetic innervation and neural growth around the VOM at the mitral isthmus. Interstitial fibrosis increased with age and heart weight was associated with AF and cardiovascular cause of death. This study increases our understanding of the cardiac autonomic innervation in the VOM area in various diseases, offering implications for the development of new therapeutic approaches targeting the autonomic nervous system.

Insufficient endobronchial ultrasound-guided transbronchial needle aspiration specimens. When and why? The analysis of criteria and reasons behind the insufficient specimens

BACKGROUND

The classification terminology systems for pulmonary cytology specimens have recently emerged. Inadequate samples, classified as "nondiagnostic," raise challenges in determining the threshold of cell numbers and the risk of malignancy (ROM).

METHODS

The study retrospectively reviewed 248 endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) samples: 46 insufficient samples, 60 low cellularity samples, and 142 adequate samples. Characteristics as cellularity, number of benign and malignant cells, and background features were assessed. Receiver operating characteristic curve analysis was performed to establish cell sufficiency thresholds for the diagnosis.

RESULTS

Out of the 248 samples analyzed, 108 were classified as benign, 94 as malignant, and 46 as insufficient. The study found that the cellularity thresholds for diagnosis in cell blocks and cytological samples were ≥50 cells and ≥100 cells, respectively. The thresholds for tumor cell counts were ≥1 - 10 cells for both types of cells, respectively. Considerably, some low cellularity samples were initially classified as insufficient despite meeting the diagnostic thresholds upon revision. The ROM varied across sample categories, with insufficient samples having a ROM of 10.9%, benign samples 15.7%, suspicious samples 92.0%, and malignant samples 100%.

CONCLUSION

Insufficient EBUS-TBNA samples raise challenges in diagnosis and management. This study identified the root cause of insufficient samples, including factors related to humans, diagnostic methods, sampling, and laboratory processing. By understanding the root causes, diagnostic recommendations can be developed to improve the diagnostic process. The findings emphasize the importance of standardized classification and terminology systems for clear communication among healthcare professionals and institutions, ultimately improving patient care and enabling quality assurance measures.

Updates in head and neck cytopathology: Insights from European Congress of Pathology Short Course

Cytological specimens play a pivotal role in head and neck nodule/mass work up and diagnoses. The specimens´ importance has grown with the onset of personalized medicine and the routine use of molecular markers in the diagnostic work up. The Updates in Head and Neck Cytopathology Short Course ran during the 35th European Congress of Pathology held in Dublin, Ireland, in 2023 and brought together experts in cytopathology, pathology, and related fields to share their expertise and experience in the field of head and neck cytopathology and its future directions. Topics such as a one-stop clinic, the Milan System for Reporting Salivary Gland Cytopathology, next generation sequencing, and human papilloma virus detection in the head and neck area were covered during the short course. These topics are briefly summarized in the present review.

Segmental arterial mediolysis leading to spontaneous rupture of splenic artery and fatal hemorrhage in pregnancy

We report an unexpected death of a 22-year-old primigravida who was admitted to the hospital with sudden abdominal pain two days before a scheduled delivery. During an emergency caesarean section due to intrauterine asphyxia, intraabdominal bleeding was observed with no apparent source of bleeding. Newly formed blood clots in the subdiaphragmatic space and arterial bleeding near the splenic hilum required a surgery on the next day. Hemorrhagic shock led to multiple organ failure on the fourth day of admission. The autopsy revealed ruptured splenic artery at the pancreatic tail and near the splenic hilum. Microscopically, different stages of segmental arterial mediolysis were observed in partially thinned and aneurysmatic artery.

How the Milan System for Reporting Salivary Gland Cytopathology works in cytopathology practice: Meta-analysis of prospective studies and comparison with retrospective studies

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is widely accepted and endorsed by professional societies. Although several studies focusing on the MSRSGC have been published, few have been prospective studies. The objective of this study was to evaluate the effectiveness of the MSRSGC in cytopathology practice.

METHODS

A comprehensive literature search was conducted to identify all prospective studies on the MSRSGC. The risk of malignancy (ROM), risk of neoplasm, and diagnostic accuracy for each diagnostic category were calculated. Data were tabulated in Microsoft Excel, and analyses were performed with the Open Meta-Analyst program.

RESULTS

Seven prospective and seven retrospective studies were identified. The total number of fine-needle aspirations (FNAs) was 1587 in the prospective studies and 1764 in the retrospective studies. The ROM values for the nondiagnostic, nonneoplastic, atypia of undetermined significance, benign neoplasm, salivary gland neoplasm of uncertain malignant potential, suspicious for malignancy, and malignant categories in prospective versus retrospective studies were 21.0% versus 26.6%, 9.4% versus 8.1%, 34.9% versus 39.6%, 2.4% versus 2.1%, 36.6% versus 31.2%, 86.0% versus 66.0%, and 97.0% versus 96.7%, respectively. Sensitivities, specificities, and diagnostic odds ratios were 83.1% (95% confidence interval [CI], 71.1%-90.8%) versus 89.1% (95% CI, 83.6%-92.9%), 98.4% (95% CI, 96.6%-99.3%) versus 94.9% (95% CI, 91.9%-96.9%), and 310.7 (95% CI, 121.2-796.6) versus 218.8 (95% CI, 107.3-438.1).

CONCLUSIONS

This meta-analysis indicated that the MSRSGC works well in FNA cytopathology practice and improves diagnostic accuracy in all diagnostic categories. The ROMs of prospective studies were in concordance with the MSRSGC reference values.

Detailed study of collagen, vasculature, and innervation in the human cardiac conduction system

BACKGROUND

The cardiac conduction system (CCS) creates and propagates electrical signals generating the heartbeat. This study aimed to assess the collagen content, vasculature, and innervation in the human sinoatrial and atrioventricular CCS, and surrounding tissue.

MATERIALS AND METHODS

Ten sinoatrial and 17 atrioventricular CCS samples were collected from 17 adult human autopsied hearts. Masson trichrome stain was used to examine collagen, cardiomyocytes, and fat proportions. Immunohistochemically, vessels and lymphatics were studied by CD31 (pan-endothelial marker) and D2-40 (lymphatic endothelium marker) antibodies. General nerve densities were assessed by S100, while sympathetic nerves were studied using tyrosine hydroxylase, parasympathetic nerves with choline acetyltransferase, and GAP43 (neural growth marker) antibodies looked at these components. All components were quantified with QuPath software (Queens University, Belfast, Northern Ireland).

RESULTS

Interstitial collagen was more than two times higher in the sinoatrial vs. atrioventricular CCS (55% vs. 22%). The fat content was 6.3% in the sinoatrial CCS and 6.5% in the atrioventricular CCS. The lymphatic vessel density was increased in the sinoatrial and atrioventricular CCS compared to the surrounding tissue and was lower in the sinoatrial vs. atrioventricular CCS (P=.043). The overall vasculature density did not differ between the SA and AV CCS. The overall innervation and neural growth densities were significantly increased in the CCS compared to the surrounding tissue. The overall innervation was higher in the atrial vs. ventricular CCS (P=.018). The neural growth was higher in the atrial vs. ventricular CCS (P=.018). The sympathetic neural supply was dominant in all the studied regions with the highest density in the sinoatrial CCS.

CONCLUSIONS

Our results provide new insights into the unique morphology of the human CCS collagen, fat, vasculature, and innervation. A deeper understanding of the CCS anatomical components and morphologic substrates' role will help in elucidating the causes of cardiac arrhythmias and provide a basis for further therapeutic interventions.

The World Health Organization Reporting System for Lung Cytopathology-A Review of the First Edition

The World Health Organization Reporting System for Lung Cytopathology is the first international system that was developed to standardize the reporting of lung cytopathology specimens across all settings of cytopathology practice. The system is composed of five diagnostic categories, which apply to all lung cytopathology specimen types. Each category contains cytomorphologic criteria, an estimated risk of malignancy, and clinical management recommendations. International uniformity in the reporting of lung cytopathology will refine the communication between cytopathologists and clinicians and ultimately improve patient care. Furthermore, standardizing the cytomorphologic criteria for each lesion will improve reproducibility among cytopathologists and highlight areas in lung cytopathology that require further research. The system also provides best practice recommendations for the selection of ancillary tests to aid in the diagnosis of each lesion, or group of lesions, keeping in mind that resources will vary across different practice settings. The goal of this review is to summarize the cytomorphologic criteria, potential diagnostic pitfalls, ancillary testing, estimated risk of malignancy, and clinical management recommendations for each diagnostic category.

Atypical urothelial cells classified according to the Paris System for Reporting Urinary Cytology: A 2-year experience with histological correlation from a Finnish tertiary care center-low rate and high risk of malignancy

BACKGROUND

The Paris System for Reporting Urinary Cytology (TPS) was issued to shift the focus of urine cytology to high-grade lesions to increase the diagnostic accuracy of urine cytology. The aim of this study was to evaluate the power of TPS in the atypical urothelial cells (AUC) category with histological correlation and follow-up.

METHODS

The data cohort consisted of 3741 voided urine samples collected during a 2-year period between January 2017 and December 2018. All samples were prospectively classified using TPS. This study focuses on the subset of 205 samples (5.5%) classified as AUC. All cytological and histological follow-up data were analyzed until 2019, and the time between each sampling was documented.

RESULTS

Of the 205 AUC cases, cytohistological correlation was possible in 97 (47.3%) cases. Of these, 36 (12.7%) were benign in histology, 27 (13.2%) were low-grade urothelial carcinomas, and 34 (16.6%) were high-grade urothelial carcinomas. Overall, the risk of malignancy was 29.8% for all cases in the AUC category, and 62.9% in the histologically confirmed cases. The risk of high-grade malignancy was 16.6% in all the AUC category samples and 35.1% in the histological follow-up group.

CONCLUSIONS

The performance of 5.5% AUC cases is considered good and within the limits proposed by TPS. TPS is widely accepted by cytotechnologists, cytopathologists, and clinicians; it improves communication and patient management.

False-Positive Atypical Endocervical Cells in Conventional Pap Smears: Cyto-Histological Correlation and Analysis

INTRODUCTION

Endocervical glandular atypia is relatively rarely diagnosed by Pap smears. A significant proportion of follow-up histological samples show no premalignant or malignant lesions. The observed cytomorphological findings in premalignant glandular lesions overlap with histologically proven reactive lesions.

METHODS

A total of 45 conventional Pap smears diagnosed as atypical endocervical cells, not otherwise specified (AEC, NOS) with human papillomavirus (HPV) status available were blindly evaluated in a search for 38 cytomorphological features representing background, architectural, cellular, and nuclear features. Of the cases, 30 represented histologically proven benign changes, and 15 represented histologically proven adenocarcinoma in situ (AIS) or endocervical adenocarcinoma (EAC) cases. The benign biopsies were re-evaluated, and the associations of the cytomorphological features or combinations of them with specific histological features and entities were statistically examined.

RESULTS

The most frequent histological findings in the benign group were squamous metaplasia, inflammation, tubal metaplasia, and microglandular hyperplasia. The statistical analysis revealed cytological features associated with squamous metaplastic changes, inflammation, and microglandular hyperplasia. Unfortunately, no cytomorphological feature was sufficiently specific to confidently leave the lesion without follow-up and histological correlation. Degeneration and nuclear crowding were the most salient features that distinguished the instances of glandular atypia with benign follow-up histology from those with histologically proven AIS or EAC (26.7 vs. 60.0%, p = 0.030, and 50.0 vs. 86.7%, p = 0.017).

CONCLUSION

Additional methods besides cytomorphology are required to reliably distinguish smears with AEC, NOS harbouring only benign histological changes from those exhibiting endocervical glandular malignancy.

Myth-busting the zone of injury concept: a prospective study on the vascular response to high-energy lower extremity trauma

BACKGROUND

Although the zone of injury concept is widely accepted, no histologic studies of vessel wall changes causing the phenomena are reported. This prospective study investigated the vascular response to high-energy lower extremity trauma to evaluate the validity of the zone of injury concept.

METHODS

The histologic appearance of arterial and venous walls in the zone of injury was studied in 19 patients (median age 46 [interquartile range 29.5-62.5] years) who underwent osteosynthesis and free-flap reconstruction due to high-energy lower extremity open fracture. Vascular samples were harvested from the injured extremity and control samples were harvested from the free-flap donor site. Histologic and morphometric characteristics of the vessels were analyzed microscopically and using digital pathology QuPath software.

RESULTS

Vascular samples were harvested on post-injury days 1-11. Intimal thickness was >3 times greater in arteries harvested from the zone of injury than in control samples (P<0.01) and the intima/media ratio was 2-fold that in control samples (P=0.01). Arterial intimal fibrosis was more evident in vessels harvested from the zone of injury (P<0.01), but medial fibrosis and medial thickness did not differ significantly between groups. Venous intimal thickening (P<0.01) and the intima/media ratio (P=0.02) were superior in samples from the zone of injury. Fibrosis-related changes did not differ between groups (P=0.45).

CONCLUSIONS

These findings support the validity of the zone of injury concept by providing a novel histologic basis for this phenomenon. Intimal thickening and arterial intimal fibrosis are prominent histologic features of vessels affected by major lower extremity trauma.

A brief review of the WHO reporting system for lung cytopathology

The International Academy of Cytology has joined with the International Agency for Research on Cancer to bring together a group of experts in lung cytopathology to develop a WHO Reporting System for Lung Cytopathology (WHO System). This System aims to improve and standardize the reporting of cytopathology, facilitate communication between cytopathologists and clinicians, and improve patient care. The WHO System describes 5 categories for reporting lung cytopathology: 'Insufficient/Inadequate/Nondiagnostic', 'Benign', 'Atypical', 'Suspicious for malignancy', and 'Malignant', each one with a clear descriptive term, a definition, a risk of malignancy, and a suggested management algorithm. The key diagnostic cytopathologic features of each of the lesions within each category have been established by consensus through an Expert Editorial Board, who are also the authors of this review and selected for each reporting system and chosen based on their expertise in the field and/or diversity of geographical representation. Many other co-authors from around the world also contributed. The assignment of writing and editing responsibilities used the same model as that used for the WHO Classification of Tumours (https://whobluebooks.iarc.fr/about/faq/). The WHO System provides the best practice application of ancillary testing, including immunocytochemistry and molecular pathology, and guides in sampling and processing techniques to optimize the handling and preparation of specimens. The WHO System was created by the authors to be applicable globally and is based on cytomorphology with possibilities for additional diagnostic management of the patient. The authors are aware that local medical and pathology resources would differ, especially in low- and middle-income countries. The WHO Tumour Classification for Thoracic Tumors, Fifth Edition, is directly accessible through the online WHO System.

Kari J. Syrjänen, MD, PhD, FIAC A Tribute to our Editor on His 75th Birthday

The Editor-in-Chief of Acta Cytologica, Prof. Kari J. Syrjänen, M.D., Ph.D., FIAC will celebrate his 75th Birthday on March 20, 2023, and we would like to offer a tribute to the 3rd Editor of Acta Cytologica and one of the pioneers in HPV research.

Ectopic thyroid in EBUS: experience from a quality assurance programme

A diagnostic challenge is presented: Distinguishing ectopic thyroid tissue from metastatic well-differentiated follicular carcinoma in cytological material. Two cases of thyroid tissue in mediastinal lymph nodes were sampled by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Later, the cases were presented in Labquality's nongynecological external quality scheme rounds in the years 2017, 2019, and 2020. The same case was presented two times, both in the 2017 and in the 2020 rounds. The results of the three rounds and the discussion of diagnostic pitfalls of ectopic thyroid tissue are presented. A total of 112 individual laboratories worldwide participated in the external quality assurance rounds with whole-slide scanned images and digital still images of alcohol-fixed Papanicolaou-stained cytospin specimens in the years 2017, 2019, and 2020. Fifty-three laboratories participated in both the 2017 (53 of 70, 75.71%) and the 2020 (53 of 85, 62.35%) rounds. The given Pap classes between rounds were compared. Twelve (12 of 53, 22.6%) of the laboratories gave the same Pap class value, whereas 32 (32 of 53, 60.4%) were in the range of ±1 class difference (Cohen's kappa -0.035, p < 0.637). When comparing the diagnoses, 21 (21 of 53, 39.6%) laboratories gave the same diagnosis in 2017 and in 2020 (Cohen's kappa 0.039, p < 0.625). Thirty-two of the laboratories gave the same diagnosis both in 2017 and in 2020 (Cohen's kappa 0.004, p < 0.979). Ten (10 of 53, 18.9%) laboratories changed their diagnose from malignant to benign, and 11 (11 of 53, 20.8%) changed their diagnose from benign to malignant between the 2017 and the 2020 rounds. In conclusions, the expert reference diagnosis was thyroid tissue in mediastinal lymph node. Thyroid tissue in mediastinal lymph node may be either of ectopic or of neoplastic origin. The diagnostic work-up should include cytomorphological, immunohistochemical, laboratory, and imaging results. If a neoplastic change is excluded, the benign category is the most feasible one. The quality assurance rounds showed a large variability in the given Pap classes. Mirroring the problematic issue both inter- and intralaboratory of such cases both in routine diagnostics and in the classification terminologies is requiring multidisciplinary evaluation approach in the diagnostics.

The diagnostic accuracy of pleomorphic adenoma in fine needle aspiration: Features leading to false positive and false negative diagnoses and the utility of cell blocks

OBJECTIVE

Fine needle aspiration (FNA) is a well-established tool in preoperative diagnosis of salivary gland lesions with diagnostic accuracy of 90%. Pleomorphic adenoma (PA) is the most common salivary gland tumor comprising 45%-74% of all salivary gland tumors with FNA diagnostic accuracy of 89.5%-96.2%. The aim of the present study was to determine and analyze potential cytomorphological pitfalls and evaluate the diagnostic accuracy in FNA diagnosis of PA.

METHODS

Salivary gland specimens with both cytological and histological diagnoses were searched over a 10-year-period (2009-2018) from a laboratory information system of Pathology Department, Fimlab Laboratories, Tampere and matched to determine concordant and discordant PA cases. Sufficient material in histological and cytological sample was found in 401 cases. In 218 cases (54.4%) diagnosis was true-negative PA, in 169 cases (42.1%) diagnosis was true-positive PA and there were 14 discordant cases: 4 false-positive cases and 10 false-negative cases. False-negative cases were reclassified and subgrouped according to The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC).

RESULTS

Cytomorphologically, cell type predominance was more often myoepithelial in true-positive cases (65%) and epithelial both in false-negative (70%, p = .007) and false-positive cases (75%, p = .027). Well-formed ducts were present in cytology in all true-positive cases (p < .001). Only 10% of true-positive cases did not show any matrix in cytology (p < .001). Nuclear changes were common in false-negative cases (80%, p = .002) and false-positive cases (75%, p = .003). Beneficial cell block (CB) was more common in true-positive cases (85%) than in false-negative cases (50%, p = .041) or in false-positive cases (50%, p = .116) and a lack of beneficial CB led more often to a false diagnosis (70% false diagnosis without beneficial CB versus 29% false diagnosis with beneficial CB).

CONCLUSION

The present study showed diagnostic accuracy of 96.5% for FNA in PA diagnosis. Sensitivity, specificity, positive predictive value and negative predictive value were 94.4%, 98.2%, 97.7%, and 95.6%, respectively. The benefit of CBs was more evident in true-positive cases (85%).

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.

Inter- and intraobserver agreement in whole-slide digital ThinPrep samples of low-grade squamous lesions of the cervix uteri with known high-risk HPV status: A multicentric international study

BACKGROUND

High-risk human papilloma virus (HR HPV) testing and liquid-based cytology are used for primary cervical screening. Digital cytology, based on whole-slide scanned samples, is a promising technique for teaching and diagnostic purposes. The aim of our study was to evaluate the interobserver and intraobserver variation in low-grade squamous lesions, HR HPV status bias, and the use of whole-slide scanned digital cervical cytology slides.

METHODS

Fifteen expert cytopathologists evaluated 71 digitalized ThinPrep slides (31 atypical squamous cells of undetermined significance [ASC-US], 21 negative for intraepithelial lesion or malignancy, and 19 low-grade squamous intraepithelial lesion cases). HR HPV data were accessible only in the second round.

RESULTS

In interobserver analysis, Kendall's coefficient of concordance was 0.52 in the first round and 0.58 in the second round. Fleiss' kappa values were 0.29 in the first round and 0.31 in the second round. In the ASC-US category, Fleiss kappa increased from 0.19 to 0.22 in the second round and the increase was even higher expressed by Kendall's coefficient: from 0.42 to 0.52. In intraobserver analysis, personal scores were higher in the second round.

CONCLUSIONS

The interobserver and intraobserver variability in low-grade squamous lesions was within fair agreement values in the present study, in line with previous works. The comparison of two rounds showed that expert cytopathologists are generally unbiased by the knowledge of HR HPV data, but that being informed of the HR HPV status leads to a better agreement. Stain quality and back discomfort were highlighted as factors affecting digital cytopathology use.

Human Pulmonary Vein Myocardial Sleeve Autonomic Neural Density and Cardiovascular Mortality

Myocardial sleeves around pulmonary veins (PVs) are highly innervated structures with heterogeneous morphological and electrophysiological characteristics. Autonomic nerve dysfunction in the myocardium may be associated with an increased risk of cardiovascular morbidity and mortality. This article studied autonomic neural remodeling in myocardial sleeves around PVs and atrial-PV ostia with immunohistochemical and morphometric methods with clinicopathological correlations. PVs were collected from 37 and atrial-PV ostia from 17 human autopsy hearts. Immunohistochemical analysis was performed using antibodies against tyrosine hydroxylase (TH), choline acetyltransferase (CHAT), and growth-associated protein 43 (GAP43). In the PV cohort, subjects with immediate cardiovascular cause of death had significantly decreased sympathetic nerve density in fibro-fatty tissue vs those with non-cardiovascular cause of death (1624.53 vs 2522.05 µm2/mm2, p=0.038). In the atrial-PV ostia cohort, parasympathetic nerve density in myocardial sleeves was significantly increased in subjects with underlying cardiovascular cause of death (19.48 µm2/mm2) than subjects with underlying non-cardiovascular cause of death with no parasympathetic nerves detected (p=0.034). Neural growth regionally varied in sympathetic nerves and was present in most of the parasympathetic nerves. Heterogeneous autonomic nerve distribution and growth around PVs and atrial-PV ostia might play a role in cardiovascular morbidity and mortality. No association in nerve density was found with atrial fibrillation.

EBUS-TBNA: A 2-Year Experience from a Tertiary Pathology Centre with Cyto-Histological Correlation

INTRODUCTION

Endoscopic ultrasound-guided fine-needle aspiration and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) methods are expanding due to their minimally invasive nature using real-time image guidance, a low incidence of complications, and a diagnostic rate ranging from 89% to 93.6%. The application of EBUS-TBNA was able to downgrade 40% of patients with suspicion of stage III lung cancer on PET scan.

METHODS

In the present study, we analysed the diagnostic outcomes of EBUS cytology at the Laboratory of Pathology, Fimlab Laboratories, Tampere, Finland, during a 2-year period. In our analysis, 1176 EBUS samples from 486 patients that underwent EBUS-TBNA in Tampere University Hospital (TAYS) from January 2017 to December 2018 were reviewed. The mean age of the patients was 64 ± 14 (SD) years with the age range from 19 to 90 years. Cytospin cytology slides stained by Papanicolaou stain and cell blocks were performed in each sample. Further immunohistochemical stains were ordered by the pathologist on demand.

RESULTS

The diagnostic yield was 89.5% and the diagnostic accuracy was 77.9% in the present study. The sensitivity for malignancy in EBUS-TBNA diagnosis was 95.69% and the negative predictive value 96.75%. Cyto-histopathological diagnosis correlation was 54.7% (95% confidence interval [CI]: 40.6%-66.4%, p < 0.001), and the histological accuracy compared to the exact original diagnosis was 43.5%. When considering the histological diagnoses that support the original diagnosis, the correlation was 61.3% (95% CI: 48.4%-71.5%, p < 0.001) and the accuracy was 72.2%. The overall inadequate rate of EBUS-TBNA samples in this study was 10.5%.

CONCLUSIONS

The EBUS-TBNA diagnostic yield, diagnostic accuracy, and inadequate rate in the present study are in line with previously published studies.

PD-L1 and PD-1 expression in thyroid follicular epithelial dysplasia: Hashimoto thyroiditis related atypia and potential papillary carcinoma precursor

Programmed cell death ligand (PD‐L1)/PD‐1 expression has been studied in a variety of cancers and blockage of PD‐L1/PD‐1 pathway is a cornerstone of immunotherapy. We studied PD‐L1/PD‐1 immunohistochemical expression in 47 thyroid gland specimens in groups of (1) Hashimoto thyroiditis (HT) only; (2) HT and follicular epithelial dysplasia (FED); and (3) HT, FED, and papillary thyroid carcinoma (PTC). PD‐1 positivity was found in immune cells, namely in lymphocytes, macrophages, and plasma cells with mean values for lymphocytes and macrophages 9% in HT group, 4% in FED group, and 4% in PTC group. PD‐L1 positivity was identified in both immune cells and in the normal epithelial cells. In the HT group, mean PD‐L1 staining on immune cells was 6%, in FED group 5%, and in PTC group 7%. The mean PD‐L1 staining on the epithelial cells in the inflammatory parenchyma was 11.7% in HT, 13.4% in FED, and 8.3% in PTC group. The mean PD‐L1 staining of FED foci was 47.2% in FED group and 33.6% in PTC group. The mean tumor proportion score (TPS) was 10.4%, and the mean combined positive score (CPS) was 15.5. At the moment, PTC is not a target of immunotherapy. However, understanding the complex issue of concurrent inflammation and autoimmunity can importantly influence the cancer treatment in future.

Endocervical Cytology: Inter- and Intra-Observer Variability in Conventional Pap Smears

INTRODUCTION

Although the cytological diagnostic criteria for cervical squamous and glandular lesions are established by the Bethesda System for Reporting Cervical Cytology, the reproducibility of the diagnosis of these lesions has been shown to be variable in previous studies. At best, occasional good kappa (κ) values were reached both inter- and intra-observerly. Generally, consensus on high-grade lesions has been better compared to milder changes.

METHODS

Altogether, 167 conventional Pap smears from 50 patients with histologically confirmed endocervical adenocarcinomas (EAC) and adenocarcinomas in situ (AIS) and from 28 patients with histologically proven high-grade intraepithelial lesions were analyzed by four cytopathologists. Twenty of the smears were later re-evaluated by the same cytopathologists. κ-values between cytopathologists in the categories of squamous versus glandular, negative for intraepithelial lesion or malignancy (NILM), atypical, and preneoplastic/neoplastic were calculated. The diagnostic Pap smears of EAC and AIS with best and worst consensus between observers were then morphologically analyzed.

RESULTS

The reproducibility ranged from poor to substantial. The overall κ-values between the four cytopathologists were 0.412, 0.314, 0.272, and 0.082, respectively, in the categories of preneoplastic/neoplastic, squamous versus glandular, NILM, and atypical. Overall intra-observer κ-values were correspondingly 0.491, 0.616, 0.345, and 0.241. In the diagnostic smears of AIS and EAC, the nuclear size >2 times the normal and nuclear pleomorphism were the commonest features associated with good diagnostic consensus and the lack of nuclear enlargement and degenerative changes were associated with poor consensus.

CONCLUSIONS

The reproducibility of preneoplasia/neoplasia diagnoses was better than that of atypia and NILM both in the inter- and intra-observer part in this study. In the smears from AIS and EAC patients, general neoplasia-associated features were more common in samples with good agreement by the four cytopathologists of the neoplastic nature and the endocervical origin of the lesion.

Application of the Milan System for Reporting Salivary Gland Cytopathology in pediatric patients: An international, multi-institutional study

BACKGROUND

Pediatric salivary gland fine-needle aspiration (FNA) is uncommon with a higher frequency of inflammatory lesions and a small proportion of malignancies. This international, multi-institutional cohort evaluated the application of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and the risk of malignancy (ROM) for each diagnostic category.

METHODS

Pediatric (0- to 21-year-old) salivary gland FNA specimens from 22 international institutions of 7 countries, including the United States, England, Italy, Greece, Finland, Brazil, and France, were retrospectively assigned to an MSRSGC diagnostic category as follows: nondiagnostic, nonneoplastic, atypia of undetermined significance (AUS), benign neoplasm, salivary gland neoplasm of uncertain malignant potential (SUMP), suspicious for malignancy (SM), or malignant. Cytology-histology correlation was performed where available, and the ROM was calculated for each MSRSGC diagnostic category.

RESULTS

The cohort of 477 aspirates was reclassified according to the MSRSGC as follows: nondiagnostic, 10.3%; nonneoplastic, 34.6%; AUS, 5.2%; benign neoplasm, 27.5%; SUMP, 7.5%; SM, 2.5%; and malignant, 12.4%. Histopathologic follow-up was available for 237 cases (49.7%). The ROMs were as follows: nondiagnostic, 5.9%; nonneoplastic, 9.1%; AUS, 35.7%; benign neoplasm, 3.3%; SUMP, 31.8%; SM, 100%; and malignant, 100%. Mucoepidermoid carcinoma was the most common malignancy (18 of 237; 7.6%), and it was followed by acinic cell carcinoma (16 of 237; 6.8%). Pleomorphic adenoma was the most common benign neoplasm (95 of 237; 40.1%).

CONCLUSIONS

The MSRSGC can be reliably applied to pediatric salivary gland FNA. The ROM of each MSRSGC category in pediatric salivary gland FNA is relatively similar to the ROM of each category in adult salivary gland FNA, although the reported rates for the different MSRSGC categories are variable across institutions.

Noninvasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP): Tumour Entity with a Short History. A Review on Challenges in Our Microscopes, Molecular and Ultrasonographic Profile

Since Noninvasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP) was introduced as a new thyroid tumour entity, many studies, and meta-analyses on diagnosing NIFTP have been published. NIFTP-revised histopathological criteria emerged in 2018. NIFTP is defined as a histological entity and its diagnosis requires a careful histological examination. Its molecular profile is similar to follicular-like tumours. Ultrasound features are unable to differentiate NIFTP. NIFTP is not a cytological diagnosis, but it influences the risk of malignancy in several categories of The Bethesda System for Reporting Thyroid Cytopathology terminology.

Code of practice for medical autopsies: a minimum standard position paper for pathology departments performing medical (hospital) autopsies in adults

The medical autopsy (also called hospital or clinical autopsy) is a highly specialised medical procedure, which requires professional expertise and suitably equipped facilities. To ensure high standards of performance, the Working Group of Autopsy Pathology of the European Society of Pathology (ESP) suggests a code of practice as a minimum standard for centres performing medical autopsies. The proposed standards exclusively address autopsies in adults, and not forensic autopsies, perinatal/or paediatric examinations. Minimum standards for organisation, standard of premises, and staffing conditions, as well as minimum requirements for level of expertise of the postmortem performing specialists, documentation, and turnaround times of the medical procedure, are presented. Medical autopsies should be performed by specialists in pathology, or by trainees under the supervision of such specialists. To maintain the required level of expertise, autopsies should be performed regularly and in a number that ensures the maintenance of good practice of all participating physicians. A minimum number of autopsies per dedicated pathologist in a centre should be at least 50, or as an average, at least one autopsy per working week. Forensic autopsies, but not paediatric/perinatal autopsies may be included in this number. Turnaround time for final reports should not exceed 3 weeks (14 working days) for autopsies without fixation of brain/spinal cord or other time-consuming additional examinations, and 6 weeks (30 working days) for those with fixation of brain/spinal cord or additional examinations.

INSM1, a Novel Biomarker for Detection of Neuroendocrine Neoplasms: Cytopathologists’ View

Background: Insulinoma-associated protein 1 (INSM1) has been considered as a novel immunostain for neuroendocrine tumors (NETs) and is hypothesized to be more reliable than first-generation NET biomarkers, such as CGA (chromogranin A), SYP (synaptophysin) and CD56 (neural cell adhesion molecule). In this review, we summarize existing literature on INSM1′s reliability as an immunostain for detection of various NETs, its results in comparison to first-generation NET biomarkers, and its expression in both non-NETs and benign tissues/cells on cytology specimens (cell blocks/smears).

Non-Invasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features Is Not a Cytological Diagnosis, but It Influences Cytological Diagnosis Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

A low-risk thyroid tumour, non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was introduced in 2016. NIFTP criteria require a thorough histological examination to rule out capsular and lymphovascular invasion, which denies the possibility of preoperative cytological diagnosis. Nevertheless, since the adoption of the new entity, the cytology of NIFTP has been a subject of interest.

OBJECTIVES

The present systematic review and meta-analysis investigate the cytological diagnosis of NIFTP.

METHOD

An online PubMed literature search was conducted between March 1, 2020, and June 30, 2020, for all original articles considering the cytology of histologically proven NIFTP. The studies including data on fine needle aspiration specimens classified by The Bethesda System for Reporting Thyroid Cytology (TBSRTC) categories, risk of malignancy (ROMs) in the TBSRTC categories, and cytomorphological features of NIFTP were included in the meta-analysis. Non-English studies and case reports were excluded. The data were tabulated and statistical analysis was performed with Open Meta-Analyst program.

RESULTS

Fifty-eight studies with a total of 2,553 NIFTP cases were included in the study. The pooled prevalence of NIFTP cases was calculated among 25,892 surgically resected cases from 20 studies and the results show that NIFTP consisted 4.4% (95% confidence interval [CI]: 3.5-5.4%) of all cases. Most of the NIFTP cases (79.0%) belonged to the intermediate categories of TBSRTC. The pooled distribution of NIFTP cases in each TBSRTC category was 1.3% (95% CI: 0.8-1.7%) in non-diagnostic (ND), 8.9% (95% CI: 6.9-10.8%) in benign, 29.2% (95% CI: 25.0-33.4%) in atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), 24.2% (95% CI: 19.6-28.9%) in follicular neoplasm (FN), 19.5% (95% CI: 16.1-22.9%) in suspicious for malignancy (SM), and 6.9% (95% CI: 5.2-8.7%) in malignant. Compared to pre-NIFTP era, the pooled risk differences of ROM were reduced by 2.4% in ND, 2.7% in benign, 8.2% in AUS/FLUS, 8.2% in FN, 7.3% in SM, and 1.1% in the malignant category. The cytomorphological features of NIFTP were similar to follicular variant of papillary thyroid carcinoma (FVPTC) but lesser to papillary thyroid carcinoma (PTC).

CONCLUSIONS

Based on our results, NIFTP remains a histological diagnosis. Although cytomorphological features cannot be used in differentiating NIFTP from FVPTC, they may guide in separating NIFTP from PTC. Features such as papillae, microfollicles, giant cells, psammoma bodies, and the amount of papillary-like nuclear features should be taken into account when suspicious of NIFTP. NIFTP should not have papillae or psammoma bodies, and giant cells were rarely observed.

The Contributory Role of Cell Blocks in Salivary Gland Neoplasms Fine Needle Aspirations Classified by the Milan System for Reporting Salivary Gland Cytology

(1) Background: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was introduced in 2018, bringing an organ-specific classification system for salivary gland cytopathology. The aim of present study is to evaluate the MSRSGC prospectively, based on a two-year experience in the tertiary care center pathology department, and evaluate the role of routine cell block (CB) preparation in salivary gland cytopathological diagnostics. (2) Methods: In our institution, the Department of Pathology, Fimlab Laboratories, Tampere, Finland, the MSRSGC has been implemented in salivary gland cytopathology since January 2018 and, over a two-year period (January 2018–December 2019), there were 365 fine-needle aspirations, of which 164 had a surgical follow-up. The CB methods used were Plasma-thrombin, the collection of visible fragments, and the Shandon and in-house methods. (3) Results: The MSRSGC diagnostic figures were as follows: accuracy 87.5%, sensitivity 45.8% and specificity 98.9%. For diagnostic categories of MSRSGC (non-neoplastic, benign neoplasm and malignant neoplasm) (n = 63) diagnostic accuracy was 98.4%, and for undetermined categories (atypia of undetermined significance, salivary gland neoplasm of uncertain malignant potential and suspicious for malignancy) (n = 49) diagnostic accuracy was 73.5%. Non-contributory cell blocks resulted more often in a false negative diagnosis (25%, 3/12) than a true negative diagnosis (10%, 7/73, p < 0.001), and is, most likely, an insufficient cytological diagnosis (86%, 18/21, p < 0.001). (4) Conclusion: The application of MSRSGC and CBs are beneficial in salivary gland cytological diagnosis, increasing diagnostic accuracy and, thus, patients’ management and treatment.

Follicular Epithelial Dysplasia as Hashimoto Thyroiditis-Related Atypia: a Series of 91 Specimens

Follicular epithelial dysplasia (FED) is described as Hashimoto thyroiditis-related atypia and is thought to be a possible precancerous lesion. Dysplasia as an interface between normal state and carcinoma is described in a wide range of diseases and carcinogenesis chains. On the other hand, inflammation-related atypia and cancerogenesis is also widely studied. In this study, we retrospectively analyzed 91 specimens of thyroid gland surgical resections with FED during a 10-year-period at the university hospital pathology department. The study population consisted of 68 females and 15 males aged between 22 and 86 years. The preoperative cytology diagnoses had mainly been in the indeterminate categories with prevailing AUS/FLUS results in the FED-only group (p = 0.005) and suspicious for malignancy and malignant in the group with FED plus adjacent malignancy. The decision for surgery was malignancy related in 48.2% of the cases. The lesions were sized 0.1-3.5 mm and multifocal in 45.1% of the cases. Immunohistochemically, the atypical cells were cyclin D1-positive in 67.5%, galectin-3 in 72.7%, CK19 in 85.7%, and HBME-1 in 87.0% of cases. In conclusion, FED is suggested to be a pathogenetic link between inflammation-related atypia and papillary carcinoma and thus a premalignant precursor of papillary carcinoma in HT as 36.1% of the specimens contained also papillary carcinoma in the present study. Both histopathological nuclear features and the immunoprofile of FED are widely shared with that of papillary carcinoma.

The Role of Cell Blocks and Immunohistochemistry in Thyroid Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance Bethesda Category

INTRODUCTION

Thyroid cytology is a widely accepted tool in the clinical triaging of nodular lesions. Cell blocks (CBs) can help in the diagnosis of atypical lesions, namely, thyroid Bethesda category of Atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS).

METHODS

In a series of 224 AUS/FLUS thyroid samples with CB, we studied CB cellularity and feasibility of 3 immunohistochemical markers (cytokeratin 19 [CK19], HBME-1, and galectin-3) apart and in combination.

RESULTS

The CBs were non-diagnostic in 34 cases. Twenty-four CBs contained <10 cells, 45 CBs 10-50 cells, and 121 CBs >50 cells. Notably, more cellularity was found in CBs performed by plasma-thrombin and in-house techniques (p < 0.001). The diagnostic accuracy to detect malignancy was 65.1% for CK19, 72.1% for HBME-1, and 70.3% for galectin-3.

CONCLUSION

In conclusion, CB cellularity is essential for successful immunohistochemistry application and further diagnostic workup of AUS/FLUS cases.

The role of Pap smear in the diagnostics of endocervical adenocarcinoma

In the high-income countries, the amount of cervical adenocarcinomas is on the rise. The pap smear sampling has a low sensitivity and a low specificity for endocervical malignancies, and there are only a few cytomorphological features, that are specifically associated with glandular atypia. In this study, 298 pap smears of 60 patients with endocervical adenocarcinoma or adenocarcinoma in situ (AIS) and 30 patients with high-grade intraepithelial lesion (HSIL) in histology were reviewed. The pap smear type (screening/clinical), the HPV status and the time from sampling to the histological confirmation of diagnosis were recorded for each case. Despite that no cytomorphological features could be associated with adenocarcinoma statistically, 70% of the pap smears were initially correctly diagnosed as an endocervical glandular lesion. Palisading cell borders, nuclear pleomorphism and the lack of single atypical cells present simultaneously were found to be associated with adenocarcinoma and AIS with the corresponding ORs of 5.89 (95% CI 1.96-17.70), 3.71 (95% CI 1.14-12.02) and 10.76 (95% CI 1.20-59.50). This combination of features was seen in smears taken up to 5 years before the histological diagnosis. Of all our screening samples, 10.9% were HPV-positive. There were no HPV-negative samples among patients with adenocarcinoma.

Primary HPV screening for cervical cancer: Results after two screening rounds in a regional screening program in Finland

INTRODUCTION

Since 2012, cervical cancer screening has been conducted with a primary high-risk human papillomavirus (hrHPV) test and conventional cytology triage in the city of Tampere, Finland. The women who were screened with the hrHPV test in 2012 were invited to participate in the second screening round in 2017. The aim of the present report was to compare the number of colposcopy referrals and the number of histological high-grade squamous intraepithelial lesion (HSIL)+ (cervical intraepithelial neoplasia [CIN2+]) lesions between the first and second screening rounds of women of a specific age group who were screened twice with the hrHPV test.

MATERIAL AND METHODS

The primary hrHPV test used was the RealTime hrHPV PCR assay by Abbott. Women with a positive hrHPV test and cytology triage equal to or worse than low-grade squamous intraepithelial lesion or atypical glandular cells, favor neoplasia, were directly referred to colposcopy, whereas hrHPV-positive women with a negative or equivocal cytology triage were re-screened after approximately 12-16 months. hrHPV-negative women were scheduled for re-screening after 5 years. The present report focuses on the cohort of women who were screened twice with the hrHPV test, who were 35-55 years old in 2012, and 40-60 years old in 2017.

RESULTS

In all, 8076 women were invited for HPV screening in 2012 and 8331 women were invited for the second round 5 years later, with attendance rates of 70% and 71%, respectively. Of the women who were screened in 2012, 4571 (69%) belonged to the 35- to 55-year age cohort. In 2017, 4807 (73%) of the women aged 40-60 years participated in the screening. In this cohort, 185 (4.0%) colposcopies were performed in the first screening round, compared with 139 (2.9%) in the second round, and the colposcopy rate was 29% smaller in the second round (P = .002). The number of histological HSIL+ cases was 38 (0.8%) during the first screening round and 29 (0.6%) during the second round (P = .220).

CONCLUSIONS

In the setting of routine organized cervical cancer screening, the initially high colposcopy rate associated with primary HPV screening seems to level off at the second screening round in women who were screened twice with an hrHPV test.

FNA diagnostics of secondary malignancies in the salivary gland: Bi-institutional experience of 36 cases

OBJECTIVE

Fine-needle aspiration (FNA) is a key diagnostic method in the evaluation of salivary gland lesions. Secondary tumors of salivary glands represent only 5% of all malignancies of major salivary glands. The goal of our study was to examine the cytological and clinical features of secondary tumors sampled by FNA.

MATERIALS AND METHODS

A series of 36 secondary tumors from the pathology departments of two university hospitals are presented. Clinical referrals to FNA, cytological features, immunohistochemical results, and histopathological diagnoses were reviewed in all cases.

RESULTS

The study population consisted of 36 cases (19 males and 17 females) with mean age 70.9 ± 13.0 years (range 41-96 years). The most common site of the metastasis was parotid gland (n = 26). The primary malignancy was known in 17 cases at the time of FNA diagnosis. The most common primary site was skin of head and neck area (11 cases) followed by lungs (n = 5) and tonsils (n = 5), kidney (n = 2) and breast (n = 2) and thyroid gland, gastrointestinal tract and soft tissue, 1 case of each. In 8 cases, the primary site remained unknown. The diagnostic or confirmatory immunocytochemistry was performed on cell blocks in 21 cases.

CONCLUSIONS

FNA is a reliable technique in the diagnosis of salivary gland secondary malignancies. The knowledge of the personal history of malignancy is essential for the successful immunocytochemical targeted diagnosis without any delay.

Assessing the diagnostic accuracy for pleomorphic adenoma and Warthin tumor by employing the Milan System for Reporting Salivary Gland Cytopathology: An international, multi-institutional study

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has established distinct diagnostic categories for reporting cytopathological findings, and each is associated with a defined risk of malignancy (ROM). However, the ROM is applied at the overall category level and is not specific for particular morphological entities within a category. Here, the diagnostic performance of the MSRSGC for pleomorphic adenoma (PA) and Warthin tumor (WT) is reported.

METHODS

The pathology archives of 11 institutions from 4 countries were retrospectively searched to identify all salivary gland fine-needle aspiration (FNA) biopsies with a differential or definitive diagnosis of PA or WT and all resection specimens with a diagnosis of PA or WT; only paired cases were included. All FNA diagnoses were retrospectively classified according to the MSRSGC.

RESULTS

A total of 1250 cases met the inclusion criteria, and they included 898 PA cases and 352 WT cases. The ROM in the benign neoplasm category was 3.0% and 1.3% for cases with a differential or definitive diagnosis of PA and WT, respectively. The ROM in the salivary gland neoplasm with uncertain malignant potential (SUMP) category was 2.7% and 18.8% for PA and WT, respectively (P = .0277). The diagnostic accuracy for PA and WT was 95.1% and 96.1%, respectively.

CONCLUSIONS

The diagnostic accuracy for PA and WT on FNA is high. Furthermore, these findings highlight the difference in the ROMs associated with 2 specific differential diagnoses in the SUMP category: basaloid neoplasms and oncocytoid neoplasms.

IgG4-positive plasma cells in Hashimoto thyroiditis: IgG4-related disease or inflammation-related IgG4-positivity?

Despite the interest of researchers in IgG4-related disease (IgG4-RD), many questions still remain unanswered regarding the thyroid gland. We aimed to clarify the relationship between IgG4-positive plasma cells and the histopathological pattern in the Hashimoto thyroiditis (HT) in a Finnish series. HT specimens (n = 280) were retrieved from the Department of Pathology, Fimlab Laboratories. After re-evaluation, 82 (29%) cases (72 females and 10 males, 52 ± 17 years) with significant fibrosis were selected. CD38, IgG and IgG4 positivity in plasma cells was evaluated by immunohistochemistry. Adjusted IgG4-positive plasma cells per HPF > 20 and IgG4- to IgG-positive plasma cell ratio > 30% were adopted as threshold criteria and related to other morphological features. IgG4-positive HT group included 13 cases (15% from fibrotic HT, 4.6% from all HT, 50 ± 15 years, 11 females) with adjusted HPF count 30 ± 5 (23-40) IgG4-positive cells. IgG4-positivity significantly correlated with the presence of lobulation, oncocytic metaplasia and certain type of fibrosis, fibrosis spread outside the gland, lymphocytes/plasma cells epithelial penetration, the predominance of microfollicles and follicular atrophy in the present study. Despite the persisting uncertainty whether HT is IgG4-RD, HT with IgG4-positive plasma cells is histopathologically distinct entity with some geographic variability.

Insulinoma-associated protein 1 (INSM-1) expression in medullary thyroid carcinoma FNA: a multi-institutional study

INTRODUCTION

Insulinoma-associated protein 1 (INSM-1) is expressed in both normal tissues and neoplasms with neuroendocrine differentiation such as small cell lung carcinoma and pancreatic neuroendocrine tumors. The aim of this study was to evaluate the INSM-1 expression in medullary thyroid carcinoma (MTC) in the aspirated material and its preoperative diagnostic value.

MATERIALS AND METHODS

MTC cases with available cytological material from 5 institutions were retrospectively identified. INSM-1 expression was analyzed in 48 cell blocks prepared from fine-needle aspiration samples from histologically confirmed cases of MTC. Twenty-nine samples were aspirates from primary thyroid lesions and 19 from secondary lesions lymph node or liver lesions. INSM-1 immunostain was done using the Ventana Automatic System (Ventana Medical Systems, Tucson, AZ). The control group consisted of 20 samples from histologically confirmed cases of papillary, follicular, and anaplastic thyroid carcinomas and secondary thyroid malignancies (squamous cell carcinoma, malignant melanoma).

RESULTS

The male to female (M:F) ratio in MTC group was 1:1.5 and the average age was 55.6 years (range: 24-84 years). INSM-1 nuclear staining in at least 5% of cells was considered positive. Forty-five (93.75%) MTC samples were positive including all primary tumor aspirates. All control samples were negative.

CONCLUSIONS

INSM-1 nuclear positivity is a reliable marker of MTC neuroendocrine differentiation on cytology material from both primary tumor and metastases. INSM-1 can also discriminate MTC from other primary and secondary thyroid carcinomas when there are cytomorphologic overlaps.

Diagnosis of myocardial infarction at autopsy: AECVP reappraisal in the light of the current clinical classification

Ischemic heart disease is one of the leading causes of morbidity and death worldwide. Consequently, myocardial infarctions are often encountered in clinical and forensic autopsies, and diagnosis can be challenging, especially in the absence of an acute coronary occlusion. Precise histopathological identification and timing of myocardial infarction in humans often remains uncertain while it can be of crucial importance, especially in a forensic setting when third person involvement or medical responsibilities are in question. A proper post-mortem diagnosis requires not only up-to-date knowledge of the ischemic coronary and myocardial pathology, but also a correct interpretation of such findings in relation to the clinical scenario of the deceased. For these reasons, it is important for pathologists to be familiar with the different clinically defined types of myocardial infarction and to discriminate myocardial infarction from other forms of myocardial injury. This article reviews present knowledge and post-mortem diagnostic methods, including post-mortem imaging, to reveal the different types of myocardial injury and the clinical-pathological correlations with currently defined types of myocardial infarction.

Thyroid Bethesda Category AUS/FLUS in Our Microscopes: Three-Year-Experience and Cyto-Histological Correlation

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) introduced a new category: Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance (AUS/FLUS) comprising of heterogenous lesions with a lesser degree of atypia. Its routine use is a bit controversial. The study cohort included AUS/FLUS thyroid cytopathological diagnoses signed out at Fimlab Laboratories from the period of 1 October 2013 to 31 December 2016. We analyzed all the AUS/FLUS cases, their cytology subclassification, and their cyto-histological correlation, when available. In total, there were 331 AUS/FLUS cases from 252 patients. The mean age was 59.8 years and there were 196 females and 56 males. Repeated AUS/FLUS was diagnosed in 75 (29.8%) cases. Out of 252 patients, 118 (46.8%) were operated on. Sixty-eight were operated on after the first AUS/FLUS diagnosis, 46 after 2 AUS/FLUS diagnoses, and 4 after 3 AUS/FLUS diagnoses. In total, there were 37 (14.7%) malignancies and 40 benign tumors. The risk of malignancy for AUS/FLUS (14.7%) is in agreement with the original TBSRTC risk of malignancy. The risk of neoplasia was 30.6% in our series.

New Cell Block Method to Enhance the Cellular Yield in Mucous and/or Bloody Samples

OBJECTIVE

Cell blocks (CBs) are used to complement cytological diagnosis and for ancillary testing. Dissatisfaction with the cellular yield of the CB is widely recognized. Various techniques have been developed to increase the diagnostic utility of CBs.

STUDY DESIGN

We invented a new CB technique to increase cellular yield and diagnostic accuracy suitable especially for mucous and/or bloody cytological samples.

RESULTS

The new CB technique is described in detail with illustrations and cases, where it increased the cellular yield and diagnostic accuracy. CBs prepared by this method are suitable also for ancillary techniques, namely immunocytochemistry.

CONCLUSIONS

The newly described method showed a better cellular yield in mucous and/or bloody cytological specimens.

Cytopathological features of secretory carcinoma of salivary glands and ancillary techniques in its diagnostics: impact of new Milan system for reporting salivary gland cytopathology

Secretory carcinoma (SC) of salivary glands is a newly described low-grade malignancy characterized by the presence of ETV6 rearrangement. Only a few cases and very small series with cytomorphology were reported so far. Six cases of fine-needle aspirations (FNAs) from afterward histologically, immunohistochemically and genetically confirmed SCs were retrieved from the archives of the authors. Ancillary immunocytochemistry (ICC) and translocation detection were performed on cell blocks (CBs). All aspirates were sufficiently cellular and cells were arranged in more or less cohesive groups with only mild nuclear polymorphism. The cytoplasm was eosinophilic, granulated and vacuolated, especially in CBs. Secretory material within the microcystic spaces was periodic acid-Schiff (PAS) positive. Triple positivity of immunomarkers S-100 protein, mammaglobin and vimentin was present. The proliferation index was low. Ancillary techniques suggested the possibility of SC in a few cytology cases; nevertheless, the final diagnosis was based on histomorphology, immunohistochemistry and genetics. The SC of salivary glands is detectable pre-operatively using ICC and genetics. The presence of the diagnostic ETV6 rearrangement increases the accuracy of FNA to the maximum. According to the Milan system, cases genetically not confirmed should be categorized as Suspicious for Malignancy or Salivary Gland Neoplasm of Uncertain Malignant Potential (SUMP), both requiring surgery.

Application of the Milan System for Reporting Submandibular Gland Cytopathology: An international, multi-institutional study

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a 6-tier diagnostic category system with associated risks of malignancy (ROMs) and management recommendations. Submandibular gland fine-needle aspiration (FNA) is uncommon with a higher frequency of inflammatory lesions and a higher relative proportion of malignancy, and this may affect the ROM and subsequent management. This study evaluated the application of the MSRSGC and the ROM for each diagnostic category for 734 submandibular gland FNAs.

METHODS

Submandibular gland FNA cytology specimens from 15 international institutions (2013-2017) were retrospectively assigned to an MSRSGC diagnostic category as follows: nondiagnostic, nonneoplastic, atypia of undetermined significance (AUS), benign neoplasm, salivary gland neoplasm of uncertain malignant potential (SUMP), suspicious for malignancy (SM), or malignant. A correlation with the available histopathologic follow-up was performed, and the ROM was calculated for each MSRSGC diagnostic category.

RESULTS

The case cohort of 734 aspirates was reclassified according to the MSRSGC as follows: nondiagnostic, 21.4% (0%-50%); nonneoplastic, 24.2% (9.1%-53.6%); AUS, 6.7% (0%-14.3%); benign neoplasm, 18.3% (0%-52.5%); SUMP, 12% (0%-37.7%); SM, 3.5% (0%-12.5%); and malignant, 13.9% (2%-31.3%). The histopathologic follow-up was available for 333 cases (45.4%). The ROMs were as follows: nondiagnostic, 10.6%; nonneoplastic, 7.5%; AUS, 27.6%; benign neoplasm, 3.2%; SUMP, 41.9%; SM, 82.3%; and malignant, 93.6%.

CONCLUSIONS

This multi-institutional study shows that the ROM of each MSRSGC category for submandibular gland FNA is similar to that reported for parotid gland FNA, although the reported rates for the different MSRSGC categories were variable across institutions. Thus, the MSRSGC can be reliably applied to submandibular gland FNA.

Cell Block in Cytological Diagnostics: Review of Preparatory Techniques

OBJECTIVE

The cell block (CB) technique refers to the processing of sediments, blood clots, or grossly visible tissue fragments from cytological specimens into paraffin blocks that can be cut and stained by the same methods used for histopathology. The technique brings additional tissue architectural information. CB can be used for ancillary techniques such as immunocytochemistry and molecular techniques.

STUDY DESIGN

We reviewed the literature on the various preparatory techniques of CBs.

RESULTS

There is a wide range of preparatory techniques for CBs and no golden standard for CBs exists: tens of methods are used in various institutions. The majority of the methods are modified in house techniques with a few commercially available kits. The techniques most commonly used are the plasma/thrombin method, the agar method, and commercially available Histogel- and Cellient CB-methods. Dissatisfaction with the cellular yield of the CBs is common.

CONCLUSIONS

In the CBs, the cytological material is preserved for future use, which is a tremendous advantage in the era of targeted therapy and biobanking. The CB is thus central to the future of cytology: more can be done with less material and with less invasiveness to the patient.

[Molecular Aspects of Thyroid Tumors with Emphasis on MicroRNA and Their Clinical Implications]

BACKGROUND

Central to neoplastic transformation and tumor progression is alteration of the signaling pathways that control cell proliferation and apoptosis. The key mechanisms for this neoplastic process are genetic changes (mutations of cancer-related genes) and recently identified epigenetic changes that involve DNA methylation, chromatin remodeling (which has a profound effect on the control of gene expression), and noncoding, regulatory RNA (notably, microRNA - miRNA). MiRNAs control expression of their target gene post-transcriptionally. These molecular factors have potential as diagnostic, prognostic, and predictive molecular markers. Epithelial tumors of the thyroid gland are a histogenetically, morphologically, and pathobiologically heterogeneous group of neoplasms and require new, molecular approaches in clinical practice.

AIM

This review aims to present contemporary scientific knowledge of this molecular (genetic and epigenetic) field of sporadic thyroid tumors of follicular cell origin and their potential clinical implications. The fundamental mutations (BRAFV600E, RET/PTC, RAS, and PAX8-PPARG) in selected tumor types are described comprehensively. Special attention is paid to miRNAs, including their biogenesis, function, and expression profiles in the most common thyroid tumors - follicular adenoma, follicular carcinoma, and papillary carcinoma.

CONCLUSION

Thyroid cancer medicine has recently entered a new, molecular era. Comprehensive knowledge of all molecular aspects may improve diagnostics and management of thyroid neoplasms through the introduction of novel, progressive treatment strategies for this cancer. Further research on signaling pathway-related targets, standardization of methods, and evaluation of results are required.Key words: thyroid tumors - cancerogenesis - genetics - epigenetics - microRNA The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 19. 10. 2016Accepted: 2. 11. 2016.

Vascular Proliferation of the Thyroid: Potential Histopathological Pitfalls as a Consequence of Fine Needle Aspiration

OBJECTIVE

Fine needle aspiration biopsy (FNAB) can cause reactive histopathological changes, commonly including haemorrhage and granulation tissue. The literature describing vascular proliferation after FNAB is sparse. We aimed to describe neovascularisation in thyroid gland specimens as a consequence of FNAB.

STUDY DESIGN

We analysed all thyroid histopathological specimens from the Fimlab Laboratories collected between 2010 and 2013 for neovascularisation and distortions in the accompanying tissue. We evaluated HE-stained slides and CD31-, podoplanin-, and Ki-67-immunostained slides.

RESULTS

We observed vascular proliferation in 64 out of 787 specimens (8.1%). In these patients, the mean age was 62 years, 43 were female and 21 were male. Previous FNAB data were available in 49 cases (76.6%). In 51 cases (79.7%), the neovascularisation occupied less than 5% of the thyroid gland area. The vessel dilatation was moderate in 28 cases (43.8%) and low in 20 cases (31.3%). In tumours, neovessels were detected within the tumour and in the surrounding tissue.

CONCLUSIONS

Post-FNAB tissue samples include dilated newly formed vessels, which pathologists should differentiate from rare thyroid vascular tumours. The proposed mechanism is a traumatically induced haemorrhage followed by haematoma and thrombosis that resolves by recanalisation. A knowledge of tissue alteration is needed to avoid misdiagnoses.

Human papillomavirus test with cytology triage in organized screening for cervical cancer

INTRODUCTION

In randomized studies, testing for high-risk (HR) human papillomavirus (hrHPV) has been more sensitive than conventional cytology in detecting cervical intraepithelial neoplasia (CIN). The aim of this study was to evaluate the performance of HPV testing in the setting of an organized routine screening program.

MATERIAL AND METHODS

Since 2012, 35- to 60-year-old women living in the city of Tampere have been screened with the Abbott RealTime hrHPV test. HPV-negative women are referred to the next screening round in five years. HPV-positive women are triaged with conventional cytology, and women with at least low-grade squamous intraepithelial lesion (LSIL⁺ ) are referred to colposcopy. The remaining HPV-positive women are referred for re-testing after 12 months, and then all HPV-positive women are referred to colposcopy. The data from the last cohort with cytological screening (screened in 2011) is presented for comparison.

RESULTS

A total 5637 (70%) women attended the first round of HPV screening, and 369 were HPV-positive. Of them, 54 women LSIL⁺ were referred to colposcopy, resulting in 16 CIN2⁺ lesions found. Of the remaining HPV-positive women, 66% were still positive one year later, and were referred to colposcopy, with 18 additional CIN2⁺ lesions found. The attendance rate to the last round of cytological screening was 71% (5814 women). Sixty-four women with LSIL⁺ cytology were referred to colposcopy, and 11 CIN2⁺ lesions were found. Of the 777 women with borderline cytology and scheduled for reflex screening in the following year, 109 (19%) had ASC-US⁺ , and 57 underwent colposcopy, resulting in six additional CIN2⁺ lesions found. The total detection rate of CIN2⁺ was significantly higher in the HPV-screened cohort (6.0/1000 vs. 2.9/1000, p = 0.015). However, the total colposcopy rate was 4% vs. 2%, respectively (p < 0.001).

CONCLUSION

Human papillomavirus testing also seems to be more sensitive than cytology in detecting CIN2⁺ lesions in the setting of a routine organized screening program, besides in the context of randomized trials. The problem of an increased colposcopy rate needs to be addressed in the future.

Talin and vinculin are downregulated in atherosclerotic plaque; Tampere Vascular Study

BACKGROUND AND AIMS

Focal adhesions (FA) play an important role in the tissue remodeling and in the maintenance of tissue integrity and homeostasis. Talin and vinculin proteins are among the major constituents of FAs contributing to cellular well-being and intercellular communication.

METHODS

Microarray analysis (MA) and qRT-PCR low-density array were implemented to analyze talin-1, talin-2, meta-vinculin and vinculin gene expression in circulating blood and arterial plaque.

RESULTS

All analyzed genes were significantly and consistently downregulated in plaques (carotid, abdominal aortic and femoral regions) compared to left internal thoracic artery (LITA) control. The use of LITA samples as controls for arterial plaque samples was validated using immunohistochemistry by comparing LITA samples with healthy arterial samples from a cadaver. Even though the differences in expression levels between stable and unstable plaques were not statistically significant, we observed further negative tendency in the expression in unstable atherosclerotic plaques. The confocal tissue imaging revealed gradient of talin-1 expression in plaque with reduction close to the vessel lumen. Similar gradient was observed for talin-2 expression in LITA controls but was not detected in plaques. This suggests that impaired tissue mechanostability affects the tissue remodeling and healing capabilities leading to development of unstable plaques.

CONCLUSIONS

The central role of talin and vinculin in cell adhesions suggests that the disintegration of the tissue in atherosclerosis could be partially driven by downregulation of these genes, leading to loosening of cell-ECM interactions and remodeling of the tissue.