Malignancies in Pleural, Peritoneal, and Pericardial Effusions

Radiographic Manifestations of Lung Cancer

Chest radiography is one of the most frequently utilized imaging procedures, offering advantages like accessibility, speed, affordability, and relatively low radiation exposure. Lung cancer is the third most prevalent cancer in the United States and results in the highest number of cancer-related deaths. Understanding the role of chest radiography in evaluating patients with lung cancer is crucial. This article explores the radiographic manifestations of lung cancer, the role of chest radiography in the management of lung cancer, its limitations, and when the use of computed tomography is indicated.

Bringing AI to Clinicians: Simplifying Pleural Effusion Cytology Diagnosis with User-Friendly Models

Background: Malignant pleural effusions (MPEs) are common in advanced lung cancer patients. Cytological examination of pleural fluid is essential for identifying cell types but presents diagnostic challenges, particularly when reactive mesothelial cells mimic neoplastic cells. AI-powered diagnostic systems have emerged as valuable tools in digital cytopathology. This study explores the applicability of machine-learning (ML) models and highlights the importance of accessible tools for clinicians, enabling them to develop AI solutions and make advanced diagnostic tools available even in resource-limited settings. The focus is on differentiating normal/reactive cells from neoplastic cells in pleural effusions linked to lung adenocarcinoma. Methods: A dataset from the Cytopathology Unit at the Sant'Andrea University Hospital comprising 969 raw images, annotated with 3130 single mesothelial cells and 3260 adenocarcinoma cells, was categorized into two classes based on morphological features. Object-detection models were developed using YOLOv8 and the latest YOLOv11 instance segmentation models. Results: The models achieved an Intersection over Union (IoU) score of 0.72, demonstrating robust performance in class prediction for both categories, with YOLOv11 showing performance improvements over YOLOv8 in different metrics. Conclusions: The application of machine learning in cytopathology offers clinicians valuable support in differential diagnosis while also expanding their ability to engage with AI tools and methodologies. The diagnosis of MPEs is marked by substantial morphological and technical variability, underscoring the need for high-quality datasets and advanced deep-learning models. These technologies have the potential to enhance data interpretation and support more effective clinical treatment strategies in the era of precision medicine.

Cytologic Histotyping of Gynecologic Malignancies in Peritoneal Fluids Is Reliable When Compared to Its Corresponding Surgical Specimen

BACKGROUND

Cytologic examination of peritoneal fluid (PTFL) often represents the first and only pathologic specimen available to guide management of gynecologic malignancies (GMs). This study examines the cytohistologic correlation between histotyping of GM in PTFL and its corresponding surgical specimen (SS).

METHODS

The study retrospectively identified positive PTFL with a GM between 2017 and 2022. Cytologic specimens (CSs) that were obtained after or concurrently with its diagnostic SS (biopsy/resection) were excluded. Root cause analysis of discordant cases was performed by reviewing morphology, specimen characteristics, and immunophenotype of CS.

RESULTS

GM affected 55.8% (502/899) of malignant PTFL, of which 15.7% (79)/22.3% (112) was the only/initial diagnostic sample, respectively. Compared to SS, when a subtype was rendered on CS (91.9%), the concordance rate is 91.2% (almost perfect agreement, K = 0.842). Factors contributing to incorrect/inadequate subtyping include specimen limitations (low volume and/or cellularity), cytopathologist preference, and insufficient immunophenotyping. In seven patients (1.4%), the CS was able to render a more definitive diagnosis than its preceding nondiagnostic SS due to the paucity of lesional cells.

CONCLUSION

When compared to SS, histotyping of GM in PTFL is reliable and, at times, can be more definitive than its surgical counterpart. In some cases, subtyping is limited by extrinsic factors (i.e., specimen limitations). In other cases, the responsible cytopathologist prefers not to subtype despite supportive morphologic and immunohistochemical features. This highlights an opportunity for improvement in the diagnosis/subtyping of GM in PTFL, which may be the initial or only diagnostic specimen prior to patient treatment.

The Diagnostic Accuracy of Claudin-4 Immunochemistry in Differentiating Metastatic Carcinomas From Mesothelial Processes in Serous Effusion Cytology: A Systematic Review and Meta-analysis

CONTEXT.—

Distinguishing metastatic carcinomas from mesotheliomas or reactive mesothelial cells in pleural, peritoneal, and pericardial effusions is a common diagnostic problem cytopathologists encounter.

OBJECTIVE.—

To perform the first meta-analysis on the pooled diagnostic accuracy of claudin-4 immunochemistry in serous effusion cytopathology.

DESIGN.—

This report followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for diagnostic test accuracy studies. Three databases (PubMed, Scopus, and the Cochrane Library) were searched until October 9, 2023, followed by study selection using specific inclusion and exclusion criteria and data extraction. The study quality assessment was performed by using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Statistical analysis was performed by using R to calculate the pooled sensitivity and specificity of claudin-4 immunochemistry. In addition, the diagnostic odds ratio was measured, representing the odds ratio of a positive result indicating a carcinoma rather than a mesothelial process in serous effusion cytology.

RESULTS.—

Fourteen observational studies, published between 2011 and 2023, fulfilled the selection criteria and were included. All 14 studies used the 3E2C1 clone. Claudin-4 immunochemistry showed a high diagnostic accuracy in serous effusion cytology. The pooled sensitivity and specificity were 98.02% (95% CI, 93.96%-99.37%) and 99.72% (95% CI, 97.36%-99.97%), respectively. Lastly, the pooled diagnostic odds ratio was 1660.5 (95% CI, 760.0-3627.8), and no evidence of statistical heterogeneity between the included studies was found (I2 = 0%, τ2 = 0).

CONCLUSIONS.—

Claudin-4 may be used as a single pan-carcinoma immunochemical biomarker in the differential diagnosis between metastatic carcinomas and mesotheliomas or reactive mesothelial cells in serous effusion cytology.

The International System for Serous Fluid Cytopathology (TIS) survey in preparation for TIS 2.0

INTRODUCTION

The International System for Serous Fluid Cytopathology (TIS) has gained acceptance and has led to literature validating original concepts and suggesting refinements. In preparation for the second edition of TIS, editors generated a survey to solicit experience with and opinions about TIS.

MATERIALS AND METHODS

An online survey available from March 8 to June 15, 2024, included 56 questions, offered in 7 languages, related to the practice of serous fluid cytopathology.

RESULTS

A total of 598 respondents accessed the survey. Information was collected regarding certification, work setting, work volume and years in practice. In the respondent group, 78% (401 of 513) were pathologists, 18% (92 of 513) cytologists of cytotechnologists, 2% (10 of 513) trainees, and 2% (10 of 513) medical scientists. A total of 23% of participants came from academia. Also, 59% of respondents were (280 of 474) from Asia, 17% Europe, 12% North America, and 10% South America. In all, 61% (287 of 474) have adopted TIS. Over 50% issue a preliminary report awaiting ancillary test results. Another 20% issue such a report depending on circumstance. The most frequent request for refinement of criteria centered around Atypia of Uncertain Significance (AUS). Only small numbers of participants provided data on diagnostic category percentage and risk of malignancy (ROM); however, those that did reported a decrease in nondiagnostic and atypical results with corresponding decreases in ROM for those categories. Variable use of cytochemical and immunocytochemical stains for resolving mesothelial proliferations was reported. Respondents indicated a desire for incorporation of recommendations on clinical management and extension of TIS into body fluid types beyond pleural, pericardial, and peritoneal.

CONCLUSIONS

This survey examines acceptance of TIS and advice for future directions.

Pericardial effusion cytology: malignancy rates, patterns of metastasis, comparison with pericardial window, and genomic correlates

INTRODUCTION

Cytologic evaluation of pericardial fluid is essential for diagnosing malignant pericardial effusions secondary to metastatic disease and for guiding appropriate clinical management; however, large cohort and up-to-date studies on malignancy rates and distribution of primary tumor sites is lacking.

MATERIALS AND METHODS

A retrospective analysis of pericardial fluid specimens from 2 large academic medical centers over a 10-year period was conducted. Clinical and specimen characteristics were correlated with cytologic diagnoses, and compared with surgical pathology pericardial specimens when available. In addition, genomic testing results were examined in a subset of malignant cases.

RESULTS

A total of 1667 pericardial fluid specimens were evaluated, with 15.3% diagnosed as malignant. Lung cancer (50.6%) was by far the most common primary tumor causing malignant pericardial effusions, followed by breast (13.0%), hematolymphoid (12.6%), and gastrointestinal (6.1%) cancers. A subset of patients with paired cytology and surgical pathology pericardial specimens showed concordance in 84.2% of cases, with discordant cases more frequently presenting with a positive cytology but negative surgical pathology result. Genomic analysis of a subset of malignant pericardial effusions revealed the most frequently mutated genes to be TP53, KRAS, CDKN2A/B, and PIK3CA, with a larger proportion of high tumor mutational burden (≥10 muts/Mb) in pericardial fluid samples compared to primary or metastatic sites.

CONCLUSIONS

While lung cancer is the most frequent cause of a cytology-confirmed malignant pericardial effusion, familiarity with relative frequencies of metastases from other sites can be particularly helpful, especially in the diagnostic work-up of an occult malignant pericardial effusion.

The Role of Chest Radiography in Lung Cancer

Chest radiography is one of the most commonly performed imaging tests, and benefits include accessibility, speed, cost, and relatively low radiation exposure. Lung cancer is the third most common cancer in the United States and is responsible for the most cancer deaths. Knowledge of the role of chest radiography in assessing patients with lung cancer is important. This article discusses radiographic manifestations of lung cancer, the utility of chest radiography in lung cancer management, as well as the limitations of chest radiography and when computed tomography (CT) is indicated.

Minimally Invasive, Maximally Effective: The Power of Precision Cytoanalysis on Effusion Samples-A Comprehensive Exploration from Traditional Methods to Innovative Approaches

Precision medicine translates through molecular assays and in minimally invasive diagnosis, evident in analyses of effusions that serve therapeutic and diagnostic purposes. This cost-effective and low-risk approach provides advantages, playing a pivotal role in late-stage oncology and frequently standing as the primary resource for cancer diagnosis and treatment pathways. This article outlines the workflow for managing serous fluid and explores how cytology effusion analysis extends beyond immunocytological diagnosis. Combined with current molecular tests it showcases the potential to be a skillful tool in precision cytopathology.

The International System for Reporting Serous Fluid Cytopathology: A Systematic Review and Meta-Analysis of Diagnostic Test Accuracy Studies

This is the first systematic review and meta-analysis of The International System (TIS) for reporting serous fluid cytopathology. Our aims were to present the pooled malignancy rate of each TIS reporting category and the diagnostic accuracy of cytology using this system. Database search using a predefined strategy was followed by study selection, data extraction, study quality assessment, and statistical analysis. Data derived from 16 eligible studies were pooled. The pooled rates of malignancy were as follows: 27% (95% CI; 16%-41%) for "nondiagnostic" (ND), 11% (95% CI; 7%-18%) for negative for malignancy" (NFM), 49% (95% CI; 37%-61%) for "atypia of undetermined significance" (AUS), 90% (95% CI; 81%-95%) for "suspicious for malignancy" (SFM), and 100% (95% CI; 98%-100%) for "positive for malignancy" (MAL). Studies performed exclusively in cancer hospitals showed higher pooled malignancy rates, compared with academic and community hospitals serving the general population, in the ND [40% (95% CI; 21%-62%) vs. 22% (95% CI; 11%-39%)], NFM [20% (95% CI; 13%-30%) vs. 9% (95% CI; 5%-17%)], and AUS categories [55% (95% CI; 47%-63%) vs. 46% (95% CI; 31%-62%)]. Notably, the difference was significant in the NFM category ( P =0.04). When both SFM and MAL cytology interpretations were considered as malignant outcomes, the pooled sensitivity and specificity were 68.74% (95% CI; 59.90%-76.39%) and 98.81% (95% CI; 98.18%-99.22%), respectively. In addition, the diagnostic odds ratio (DOR) was found to be 170.7 (95% CI; 96.2-303.3). Despite its strengths, our study also had some limitations. Therefore, future large-scale longitudinal studies could strengthen the findings of this review.

Multiple serous cavity effusion screening based on smear images using vision transformer

Serous cavity effusion is a prevalent pathological condition encountered in clinical settings. Fluid samples obtained from these effusions are vital for diagnostic and therapeutic purposes. Traditionally, cytological examination of smears is a common method for diagnosing serous cavity effusion, renowned for its convenience. However, this technique presents limitations that can compromise its efficiency and diagnostic accuracy. This study aims to overcome these challenges and introduce an improved method for the precise detection of malignant cells in serous cavity effusions. We have developed a transformer-based classification framework, specifically employing the vision transformer (ViT) model, to fulfill this objective. Our research involved collecting smear images and corresponding cytological reports from 161 patients who underwent serous cavity drainage. We meticulously annotated 4836 patches from these images, identifying regions with and without malignant cells, thus creating a unique dataset for smear image classification. The findings of our study reveal that deep learning models, particularly the ViT model, exhibit remarkable accuracy in classifying patches as malignant or non-malignant. The ViT model achieved an impressive area under the receiver operating characteristic curve (AUROC) of 0.99, surpassing the performance of the convolutional neural network (CNN) model, which recorded an AUROC of 0.86. Additionally, we validated our models using an external cohort of 127 patients. The ViT model sustained its high-level screening performance, achieving an AUROC of 0.98 at the patient level, compared to the CNN model's AUROC of 0.84. The visualization of our ViT models confirmed their capability to precisely identify regions containing malignant cells in multiple serous cavity effusion smear images. In summary, our study demonstrates the potential of deep learning models, particularly the ViT model, in automating the screening process for serous cavity effusions. These models offer significant assistance to cytologists in enhancing diagnostic accuracy and efficiency. The ViT model stands out for its advanced self-attention mechanism, making it exceptionally suitable for tasks that necessitate detailed analysis of small, sparsely distributed targets like cellular clusters in serous cavity effusions.

The spectrum of malignant diagnoses in cerebrospinal fluid cytology from an adult population: a multi-institutional retrospective review

INTRODUCTION

Limited updated literature exists about the prevalence and spectrum of malignancies involving cerebrospinal fluid (CSF). In this multi-institutional study, we review our experience with focus on first time malignancy diagnosis in CSF samples of adults.

MATERIALS AND METHODS

Institutional databases at 4 academic centers were queried retrospectively for CSFs over a 10-year period. The following data elements were collected: total # of CSFs, total # of CSFs with a malignant diagnosis; for each patient with a first time CSF diagnosis of malignancy: age, gender, diagnosis, prior history of malignancy, and ancillary studies.

RESULTS

Twenty-four thousand one hundred forty-two CSFs were collected with a positive for malignancy rate of 2.3% (n = 551). Out of 347 (1.4%) adults with a first-time diagnosis of CSF malignancy 182 (52%) were female (age range: 19-89/mean: 57) and 165 (48%) were male (age range: 20-95/mean: 60). Hematolymphoid malignancies (48%, n = 168) were overall the most common neoplasm. In women, metastatic carcinomas (63%, n = 114) were the leading malignancy, of which the majority were breast primaries. In men, lymphomas/leukemias (64%, n = 106) were the leading malignancy, of which the majority were B-cell lymphomas. Ancillary studies aided the final diagnosis in 110 (32%) cases. For 286 (82%) cases, a prior history of malignancy was available to correlate CSF findings.

CONCLUSIONS

A malignancy diagnosis in the CSF of adults is rare. The most common malignancies in females and males are metastatic breast carcinoma and hematolymphoid malignancies, respectively. Metastatic neoplasms account for the majority, with primary central nervous system neoplasms being quite uncommon. History of malignancy and ancillary tests can be helpful.

Optimal fluid volume for detecting malignancy in serous effusions: a single institution experience

INTRODUCTION

Detection of malignant cells in serous fluids is an indicator of advanced stage of malignancy and is critical in clinical management decisions and prompt treatment initiation. The minimum volume which is ideal for detecting malignancy in serous fluid is not well established. In this study, we aim to identify optimal volume that will be ideal for adequate cytopathological diagnosis.

MATERIALS AND METHODS

A total of 1597 samples of serous fluids from 1134 patients were included in the study. Samples were diagnosed based on International System for Reporting Serous Fluid Cytopathology (ISRSFC). Clinicopathologic results from different diagnostic groups were compared and statistically analyzed.

RESULTS

Pleural fluids comprised 890 (55.7%) specimens, followed by 456 (28.6%) peritoneal, 128 (8%) ascites, and 123 (7.7%) pericardial fluid specimens. The majority were negative for malignancy (1138, 71.3%), followed by malignant (376, 23.5%), atypical (59, 3.7%), and suspicious for malignancy (24, 1.5%). Malignancy was identified in sample with volumes from 5 mL to 5000 mL. Rate of detection of malignant cells increased significantly with higher sample volumes. For malignancy detection the optimal volume for overall serous fluid is 70 mL. Pericardial fluid is an exception, with lower mean volume and significantly lower proportion of cases with malignant diagnosis.

CONCLUSIONS

Our study indicates that higher fluid volumes have a higher rate of malignancy detection and a low false-negative rate. We recommend a minimum of 70 mL of serous fluid for optimal cytopathologic examination and malignancy detection. Pericardial fluid is an exception, with lower mean volume and thus lower requirement.

Discrepancies in Hormone Receptor and HER2 Expression between Malignant Serous Effusions and Paired Tissues from Primary or Recurrent Breast Cancers

INTRODUCTION

Immunohistochemistry (IHC) for the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) biomarkers has prognostic and therapeutic value in breast cancer. This study aimed to compare the expression of ER, PR, and HER2 between paired malignant effusions and tissue samples of breast cancer.

METHODS

Our electronic archive was searched for all effusions diagnosed as breast carcinomas within a pre-defined period (January 2018-October 2021). Next, their cell blocks (CBs) were subjected to ER, PR, HER2 IHC, or in situ hybridization, in addition to EGFR IHC. The expression of hormone receptors (HRs) and HER2 was subsequently compared between tissue and effusion cytology samples derived from the same patients.

RESULTS

Only 2/76 (2.6%) of the breast cancer patients analyzed showed a malignant effusion at their initial presentation. ER, PR, and HER2 discordance rates between paired malignant effusions and tissue samples obtained at initial diagnosis were 24.3% (17/73), 40.8% (29/71), and 9.1% (6/66), respectively. The HR-/HER2- status was found more often at effusions compared to paired tissue biopsies obtained at initial diagnosis (30/70 vs. 17/70; p < 0.001). In addition, the HR-/HER2- status was significantly associated with an earlier development of a malignant effusion, when found at initial diagnosis (p < 0.001; log-rank test), first recurrence/metastasis (either solid or effusion) (p = 0.012; log-rank test), effusion samples (p = 0.007; log-rank test), and any tumor sample obtained (p = 0.009; log-rank test). Lastly, EGFR overexpression in the HR-/HER2- effusion samples was significantly associated with a shorter post-effusion survival (p = 0.019; log-rank test).

CONCLUSION

Serous effusion cytology provides high-quality material for ancillary techniques, especially when CBs are prepared, reflecting cancer heterogeneity.

Deep Learning-Based Computational Cytopathologic Diagnosis of Metastatic Breast Carcinoma in Pleural Fluid

A Pleural effusion cytology is vital for treating metastatic breast cancer; however, concerns have arisen regarding the low accuracy and inter-observer variability in cytologic diagnosis. Although artificial intelligence-based image analysis has shown promise in cytopathology research, its application in diagnosing breast cancer in pleural fluid remains unexplored. To overcome these limitations, we evaluate the diagnostic accuracy of an artificial intelligence-based model using a large collection of cytopathological slides, to detect the malignant pleural effusion cytology associated with breast cancer. This study includes a total of 569 cytological slides of malignant pleural effusion of metastatic breast cancer from various institutions. We extracted 34,221 augmented image patches from whole-slide images and trained and validated a deep convolutional neural network model (DCNN) (Inception-ResNet-V2) with the images. Using this model, we classified 845 randomly selected patches, which were reviewed by three pathologists to compare their accuracy. The DCNN model outperforms the pathologists by demonstrating higher accuracy, sensitivity, and specificity compared to the pathologists (81.1% vs. 68.7%, 95.0% vs. 72.5%, and 98.6% vs. 88.9%, respectively). The pathologists reviewed the discordant cases of DCNN. After re-examination, the average accuracy, sensitivity, and specificity of the pathologists improved to 87.9, 80.2, and 95.7%, respectively. This study shows that DCNN can accurately diagnose malignant pleural effusion cytology in breast cancer and has the potential to support pathologists.

Malignant effusions secondary to metastatic thyroid carcinomas: A review of 15 cases

BACKGROUND

Malignant effusions secondary to thyroid carcinomas are rare, and publications on this topic are limited. This study presents a large cohort of thyroid carcinomas involving effusion cytology.

METHODS

A 20-year computerized search for fluid cytology diagnosed with thyroid malignancy was performed. The following data were collected: patients' demographics, clinical findings, and histologic diagnoses. The cytology slides and ancillary tests were reviewed.

RESULTS

Among 47,593 specimens, 15 thyroid carcinomas involving the pleural fluid from 11 patients were found. There were six males and five females with a mean age of 72 years. Ten patients with available follow-up died of their disease. Papillary thyroid carcinoma (PTC) was the only histologic type. Ten cytology cases were available for review. The cytologic findings common to all cases were nonspecific (clusters/three-dimensional architecture, enlarged irregular nuclei, and scant to abundant to vacuolated cytoplasm). The classic PTC features were not present in all cases (fine/powdery chromatin [80%], micronucleoli [70%], nuclear grooves [50%], papillary-like architecture [40%], psammoma bodies [40%], and pseudo-nuclear inclusions [20%; present on the cell block only]). In 11 of the 15 cases, the diagnosis was rendered with immunohistochemical stains performed on the cell block (paired box 8, thyroid transcription factor 1, and thyroglobulin). In four of the 15 cases, the cytologic diagnosis was made after a comparison with prior surgical pathology or fluid cytology.

CONCLUSIONS

PTC is the most common histologic type of thyroid malignancy involving pleural effusion. Because the cytologic findings are nonspecific and classic PTC features are not always present, the clinical history in conjunction with immunohistochemical stains is helpful in arriving at the correct diagnosis.

Diagnostic Accuracy of Cell Block and Immunohistochemistry in Effusion Cytology

Introduction Although the cytology of effusion fluids is considered a routine laboratory test, it has recently emerged as an essential tool in determining the primary site of origin of carcinoma of unknown primary. The sensitivity for diagnosing malignancy has enhanced with the inclusion of cytospin, cell block (CB), and immunohistochemistry (IHC) to effusion fluid cytology due to the improvement in morphological preservation and good cellular yield. The purpose of this study was to assess the diagnostic yield, sensitivity, specificity, positive predictive value, and negative predictive value of IHC and CB in effusion cytology. Methodology An institution-based cross-sectional study was conducted over a period of six months on 150 cases of effusion fluids submitted for diagnostic purposes. After the preparation of cytospin, the residual amount of centrifuged deposit was mixed with CytoLyt solution, thrombin, and plasma, and CBs were prepared. IHC was applied to the CB. Calretinin was used for mesothelial cells, and BerEP4, TTF-1, ER, WT-1, and CD-X2 were used for the confirmation and origin of malignant cells. Results The mean age of the patients was 51.75 ± 16.63 years. The male-to-female ratio was 1:1.24. Out of 150 cases, 78 were pleural effusions, 68 were peritoneal effusions, and four were pericardial effusions. Out of 150 cases, based on cytological examination alone, 66 (44%) were classified as benign, 27 (18%) as malignant, and 57 (38%) were suspicious for malignancy. When cytology was combined with CB and IHC, the diagnostic yield was increased to benign 95 (63.33%), malignant 48 (32%), and suspicious for malignancy 7 (4.67%). The most common cause of malignant pleural effusion was breast carcinoma in females and lung carcinoma in males. The most common primary tumor in malignant peritoneal effusion was ovarian carcinoma in females and colonic adenocarcinoma in males. The sensitivity and specificity of combined cytology with cell block and IHC were 92.31% and 98.95%, respectively. This combination produced significantly better results (p-value = 0.001) for detecting malignancy and reduced suspicious cases from 38% to 4%. Conclusion CB, in combination with IHC, increases the diagnostic yield and aids in detecting malignancy at an unknown primary site in effusion fluids. Both of these techniques can thus enhance the sensitivity and specificity of the diagnosis of effusion cytology. Hence, CB and IHC have advanced utility over cytological smears in effusion fluid cytological diagnosis.

Concomitant intravascular and extravascular obstructive shock: a case report of cardiac angiosarcoma presenting with pericardial tamponade

Atraumatic pericardial tamponade and intracardiac masses are both recognized etiologies of acute obstructive shock. Pericardial tamponade, is a cardiovascular emergency commonly considered by emergency physicians and, as a result, evaluation for this process has been incorporated into standardized point of care ultrasound algorithms for assessing hypotension. Obstructive shock secondary to intracardiac tumors is an atypical clinical presentation, and although it is evaluated by the same ultrasound imaging modality, it is generally not considered or evaluated for in the emergency department setting. The concomitant presentation of these two pathologic processes is an extremely rare oncologic emergency. Existing literature on the subject is found in a small number of case reports with nearly no prior descriptions in emergency medicine references. In the right clinical context this unique presentation should be considered and evaluated for in the emergency department via point of care ultrasound modality to help guide in the management of the resulting obstructive shock.

Reassessing the optimal volume for malignancy detection in serous fluid cytology

BACKGROUND

The international system for reporting serous fluid cytopathology (TIS) recommends submitting at least 50-75 mL of serous fluid to decrease false-negative results. However, prior studies did not agree on specific volume requirements or consensus adequacy criteria. Our study aims to assess whether fluid volume affects the adequacy rate and to assess the minimum volume necessary for optimal adequacy in pleural and peritoneal fluids.

METHODS

A total of 8530 serous fluid cytology cases were identified in the laboratory information system. Differences in mean fluid volume received in the laboratory were compared using an ANOVA Games-Howell test based on TIS category. The percentage of malignant diagnoses across the volume ranges of 0 to 5 mL, 5 to 10 mL, 10 to 25 mL, 25 to 50 mL, 50 to 75 mL, 75 to 100 mL, 100 to 150 mL, 150 to 250 mL, 250 to 500 mL, 500 to 2000 mL was compared in pleural and peritoneal fluids using a chi-square test, and a SiZer analysis was performed.

RESULTS

Mean fluid volume in inadequate, atypical, and negative cases was significantly lower compared to positive cases. A SiZer analysis showed a positive relationship between the malignancy fraction of pleural and peritoneal fluids and fluid volume. The percentage of malignant diagnoses in pleural and peritoneal fluid samples increased significantly up to a volume range of 75-100 mL.

CONCLUSIONS

There is a significant relationship between fluid volume, adequacy and detection of malignancy in serous effusion cytopathology. The malignancy fraction increases with larger fluid volumes but at least 75-100 mL of fluid should be submitted for optimal diagnosis of malignancy in pleural and peritoneal fluids.

Serous cavity metastasis: Evaluation of unknown primary

Malignant effusions can occur in patients with neoplasia. Once a metastatic diagnosis is confirmed, the primary site of origin of malignancy needs to be ascertained. This task can be challenging without a prior history of malignancy. In some patients their effusion may be the initial presentation of an underlying malignancy. Metastases usually present with a dual population of mesothelial and malignant cells. Combining cytomorphologic examination with ancillary testing such as immunocytochemistry can help identify the origin of the foreign malignant cell population. Helpful architectural clues include a single cell pattern, solid cell ball pattern, single file arrangement, papillary formation, psammoma bodies and background mucin. Useful cellular features include the presence of signet ring cells, small cells, pleomorphic and multinucleated giant cells, squamous cells, spindle cells and pigmentation. Rarely, despite an extensive work-up the primary site of origin for a malignant effusion may remain unresolved. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Cytopathologic Diagnosis of Serous Fluids.

Claudin-18 Immunohistochemical Staining Facilitates the Identification of Metastatic Carcinoma of Gastric or Pancreatic Origin in Effusion Specimens

Determining the primary origin of a malignant effusion remains a common challenge for cytopathologists. Although immunohistochemical (IHC) markers are available for most primary sites, ideal IHC markers for metastatic gastric adenocarcinoma and pancreatic ductal adenocarcinoma are lacking, and related interpretation is often hindered by mesothelial cells. We recently revealed that claudin-18 IHC staining is useful for identifying the stomach and pancreas as the primary sites of metastatic adenocarcinoma. Thus, we assessed the use of claudin-18 IHC staining in 111 cell blocks obtained from various metastatic cancers and specimens negative for malignancy. Positive membranous claudin-18 staining was noted in all 10 (100%) metastatic pancreatic ductal adenocarcinomas, 9 (90%) of 10 gastric adenocarcinomas, and 1 (9%) of 11 nonmucinous lung adenocarcinomas. The cases of metastatic mucinous carcinomas of lung origin (1 case) and ovarian origin (1 case) were also positive for claudin-18. The other remaining 89 cases showed variable cytoplasmic staining on some cells (73 cases) or complete absence of staining (16 cases). After normalization to the tumor frequency, the sensitivity and specificity for identifying the stomach or pancreas as primary tumor sites in ascites were 95% (confidence interval: 0.83-0.99) and 99% (confidence interval: 0.94-1), respectively. In conclusion, membranous claudin-18 staining is a useful marker for metastatic gastric adenocarcinoma and pancreatic ductal adenocarcinoma in effusion specimens.

Preliminary cytomorphologic diagnosis of hematolymphoid malignancies in effusions: A cyto-histo correlation with lessons on restraint

Background:

Effusions as part of hematologic neoplasms are rare and as a primary presentation, rarer. In standalone laboratories of developing countries, resorting to techniques such as flow cytometry or immunohisto/cytochemistry may not be possible. A near definitive diagnosis on cytomorphology would, therefore, be an ideal beginning. To that end, we compiled our cases of primary hematolymphoid effusions, devising reproducible reporting categories and looked at their concordance with the final histopathology.

Subjects and Methods:

Fifty-four cases of primary hematolymphoid effusions over 10 years with cytology-histopathology correlation were chosen. Post morphology assessment, the cases were organized into six categories: suspicious of hematolymphoid malignancy, non-Hodgkin lymphoma-high-grade (NHL-HG), low-grade NHL (NHL-LG), Burkitt lymphoma, acute leukemias, and plasma cell dyscrasias. Discordance with histology was assigned as major and minor based mainly on therapeutic implications.

Results:

Concordance was seen in a good number (81.5%) of cases. The NHL-HG and NHL-LG categories contributed to 33.3% each of major discordance. Tuberculosis and epithelial malignancies comprised the bulk of the major discordance. Overdiagnosis of a high-grade lymphoma for a histologically proven low-grade follicular lymphoma was the only case with minor discordance.

Conclusion:

The cytologic categories used are not foolproof for hematologic neoplasms but have a fairly good concordance. A scanty abnormal population should always be viewed with suspicion and definitive labels should be avoided. While morphologic examination is fraught with danger, a good assessment directs the judicious selection of ancillary methods, and hence cannot be supplanted.

Clinico-cytopathologic analysis of 574 Pericardial Effusion Specimens: Application of the international system for reporting serous fluid cytopathology (ISRSFC) and long-term clinical follow-up

INTRODUCTION

A pericardial effusion (PE) has a variable etiology and the primary role is diagnosis of metastatic malignancy. We analyzed the PE cytology in a large cohort in accordance with the international system for reporting serous fluid cytopathology (ISRSFC) and evaluated the long-term patient outcomes.

METHODS

PE specimens from 2010 to 2014 with an available clinical history, cytologic data, and pericardial biopsy results were collected.

RESULTS

A total of 574 PE specimens were obtained from 486 patients, representing 1.5% (574/38,589) of all body fluid specimens. Three hundred and eighty-two (66.6%) cases were "negative," 54 (9.4%) cases were "atypia of undetermined significance," 10 (1.7%) cases were "suspicious for malignancy," and 128 (22.3%) cases were "malignancy". The most common origin for malignant PE was the lung (82.1%), in both men (70.5%) and women (50.6%). Breast cancer (20%) in women and gastric cancer (4.9%) in men were the second most common malignant PE, respectively. The mean interval from the occurrence of malignant PE to death was 10.06 months (range; 0-116.03 months, median 3.5 months), and the 1-year survival rate was 16.7%. In addition, the 1-year survival rates after malignant PE onset were 0% for gastric cancer, 13.9% for lung cancer, 19.8% for breast cancer, and 21.1% for the other cancers (p = 0.011).

CONCLUSION

Our present study is the first to our knowledge to classify the pericardial fluid from 574 cases in accordance with the recently published ISRSFC, and to present the long-term outcomes of patients with malignant PE at the same time. Moreover, we report for the first time that it is gastric and not lung cancer patients that have the poorest prognosis after the occurrence of malignant PE.

A Clinico-Pathologic Approach to the Differential Diagnosis of Pericardial Tumors

PURPOSE OF REVIEW

Tumors of the pericardium are rare, but a wide variety of congenital, infectious, inflammatory, and neoplastic processes have been reported. Pericardial tumors can be categorized as non-neoplastic or neoplastic. Neoplastic lesions can be further divided into benign or malignant, with malignancies being either primary or secondary (metastatic). Clinical, radiographic, and pathologic features of the most common entities are discussed.

RECENT FINDINGS

Metastatic neoplasms involving the heart and pericardium are far more common than primary pericardial neoplasms. Of primary pericardial malignancies, mesothelioma is the most common; notably, cytology of effusion fluid is relatively insensitive to the diagnosis. The prognosis for most malignancies of the pericardium, primary or secondary, is poor. Increasingly, clinically recognized diseases that involve the pericardium include Erdheim-Chester and IgG4-related disease. This article provides a comprehensive review of the most recent literature to develop a structured framework to the differential diagnosis of pericardial tumors.

Bone and soft tissue sarcomas in cerebrospinal fluid and effusion: A 20-year review at our institution

BACKGROUND

The literature on bone and soft tissue sarcomas (BSTSs) involving effusions and cerebrospinal fluid (CSF) is very limited.

METHODS

A computerized search for fluid cytology with a sarcoma diagnosis from 2000 to 2020 was performed. All available cases, including the clinical follow-up, were reviewed.

RESULTS

A total of 57 fluids specimens from 36 BSTSs were identified (9 rhabdomyosarcomas, 6 angiosarcomas, 5 epithelioid hemangioendotheliomas, 3 dedifferentiated liposarcomas, 2 chondrosarcomas, 1 extraskeletal myxoid chondrosarcoma, 3 Ewing sarcomas, 2 undifferentiated sarcomas, 3 osteosarcomas, 1 synovial sarcoma, and 1 hybrid low-grade fibromyxoid sarcoma/sclerosing epithelioid fibrosarcoma). There were 22 males and 14 females. The age range was 4 to 82 years (median, 45 years). Sites of involvement included pleural fluid (n = 38), peritoneal fluid (n = 14), and CSF (n = 5). Twenty-four cytology cases were available for review. The cytologic features were nonspecific and ranged from dyshesive to clusters of round, epithelioid, pleomorphic, and occasionally spindle-shaped malignant cells that could easily mimic other non-BSTS malignant tumors. The diagnosis of BSTS was made by comparison with a prior specimen and/or ancillary studies (molecular or immunohistochemical stains). The prognosis was poor because 95% of the patients died of their disease.

CONCLUSIONS

The incidence of BSTS in fluid cytology is extremely rare, and it can have cytologic features similar to those of non-BSTS malignancies. Although, in most cases, a comparison with a prior known BSTS specimen may suffice, the use of ancillary studies is extremely helpful in arriving at the correct diagnosis. However, in cases with no known prior malignancy, including BSTS in the differential diagnosis is prudent for preventing misdiagnosis.

Immunocytochemistry for diagnostic cytopathology-A practical guide

Cytological specimens, which are obtained by minimally invasive methods, are an excellent source of diagnostic material. Sometimes they are the only material available for diagnosis as well as for prognostic/predictive markers. When cytomorphology is not straightforward, ancillary tests may be required for a definitive diagnosis to guide clinical management. Immunocytochemistry (ICC) is the most common and practical ancillary tool used to reach a diagnosis when cytomorphology is equivocal, to differentiate entities with overlapping morphological features, and to determine the cell lineage and the site of origin of a metastatic neoplasm. Numerous immunomarkers are available, and some are expressed in multiple neoplasms. To rule out entities within a differential diagnosis, the use of more than one marker, sometimes panels, is necessary. ICC panels for diagnostic purposes should be customised based on the clinical context and cytomorphology, and the markers should be used judiciously to preserve material for additional tests for targeted therapies in the appropriate setting. This review offers a practical guide for the use of ICC for diagnostic cytopathology, covering the most commonly encountered non-hematolymphoid diagnostic scenarios in various body sites.

Cytomorphology, Immunophenotype, and cytogenetic profile of leukemic serous effusions

BACKGROUND

Serous effusions (SE) in leukemic patients can be due to infections, therapy, volume overload, lymphatic obstruction or malignancy having implications on treatment and mortality. The objective of the present study is to highlight the spectrum of cytomorphology, immunophenotype, and cytogenetics in leukemic serous effusions (LSE).

MATERIALS

Present study is retrospective and descriptive. We reviewed all the SE, which were reported as suspicious or positive of leukemic infiltration from 2016 to 2019 for cytomorphological features. CSF and effusions involved by lymphomas were excluded. Cyto-diagnosis was compared with primary proven diagnosis (by ancillary techniques) and disconcordant cases were analyzed.

RESULTS

Out of total 9723 effusions, only 0.4% (n = 40) showed leukemic involvement and included nine cases of AML, three of B-ALL, 13 T-ALL, 2 MPAL, 6 CML, 5CLL, one each of chronic myelomonocytic leukemia and AML with myelodysplasia. The most common site of involvement was the pleural cavity (n = 30), followed by the peritoneal cavity (n = 7) and the pericardial cavity (n = 3). T -ALL (41.9%) was the most common leukemia involving pleural fluid followed by AML (23.3%). CML (42.8%) was the most common leukemia involving the ascitic fluid followed by B-ALL (28.6%). Accurate diagnosis was given on cytomorphology in 72.5% (29/40) cases and 15.0% (6/40) were reported as non-Hodgkin lymphoma.

CONCLUSION

Cytology is an effective tool available to make a diagnosis of LSE. Nuclear indentations in large atypical cells and cells with eosinophilic granular cytoplasm with sparse or abundant eosinophils in the background are an important clue in favor of leukemia over lymphoma.

Ber-EP4 staining in effusion cytology: A potential source of false positives

The distinction between reactive mesothelium and carcinoma in serous effusions can be very difficult. Immunocytochemistry (ICC) is the most widely used tool to improve the diagnostic accuracy of body fluid cytology, with several ICC markers being proposed. Ber-EP4 antibody has shown high sensitivity and specificity rates for diagnosing metastatic carcinoma. In our department, we have detected Ber-EP4 positivity in mesothelium in some cytological specimens. We reviewed all articles on Ber-EP4 staining in effusion cytology, summarized current findings and analyzed the staining pattern of all cases expressing Ber-EP4. Some cases showing Ber-EP4 positivity in mesothelium have been reported, most of which showed only weak Ber-EP4 staining or staining of less than 50% of mesothelial cells. However, some cases may show strong positivity both in cytological and histological specimens. Clinicians and pathologists should be aware of this source of misdiagnosis, and ICC results in mesothelium should be always interpreted cautiously and correlated with clinical tests, other ICC markers and patient's previous history.

Postoperative circulating tumor cells: An early predictor of extrahepatic metastases in patients with hepatocellular carcinoma undergoing curative surgical resection

BACKGROUND

Postoperative extrahepatic metastases (EHM) contribute to a grim outcome in patients with hepatocellular carcinoma (HCC) who are undergoing curative surgical resection. The current study investigated the clinical value of circulating tumor cells (CTCs) in predicting EHM after curative surgery.

METHODS

A total of 197 patients with HCC who were undergoing curative surgical resection were assigned to a retrospective training cohort (144 patients) or a prospective validation cohort (53 patients). The CELLSEARCH system was used for the detection of CTCs prior to surgical resection and 1 month thereafter. The cutoff value of CTCs was estimated using receiver operating characteristic analysis. Bonferroni correction was applied for multiple testing in a Cox proportional hazards regression model.

RESULTS

In the training cohort, EHM was found to be associated with a higher postoperative CTC burden compared with no EHM (mean: 4.33 vs 0.52; P < .001). Receiver operating characteristic analysis demonstrated a postoperative CTC count ≥3 as the optimal cutoff value for the prediction of EHM. Patients with a postoperative CTC count ≥3 experienced a higher EHM risk (56.3% vs 5.5%) and a shorter median overall survival (31.25 months vs not reached) (all P < .001). The prognostic significance of a postoperative CTC count ≥3 also applied to patient subgroups with a low EHM risk, such as those with an α-fetoprotein level ≤400 ng/mL, absence of vascular invasion, well differentiation, and early tumor stage, and its predictive value was retained in patients with a continuous normal α-fetoprotein level during postoperative follow-up (all P < .05). The results were confirmed in the validation cohort.

CONCLUSIONS

A postoperative CTC count ≥3 appears to be a surrogate marker for the prediction of EHM after curative surgical resection of HCC. More careful surveillance should be recommended to patients with a high CTC load to ensure the greater possibility of early interventions for postoperative EHM.

Diagnosis and categorization of malignant effusions: A 6-year review from a single academic institution

BACKGROUND

Cytologic detection of malignant cells in pleural, peritoneal, or pericardial effusion most likely indicates advanced stage of malignant disease. There are a few studies updating the categorization of malignant effusions.

METHODS

The electronic pathology database was searched to identify consecutive cases of malignant effusion during a 6-year period. Patient age and gender, origins of known malignancy, and cytologic diagnoses were recorded and summarized.

RESULTS

A total of 1059 specimens included 561 (53%) pleural, 441 (41.6%) peritoneal, and 57 (5.4%) pericardial fluids. Most of the pleural (516, 92.0%), peritoneal (418, 94.8%), and pericardial (53, 93.0%) specimens were derived from patients with a single known malignancy. More common origins involving pleural fluid were lung (152, 27.1%) followed by breast (103, 18.4%) and gastrointestinal tract (76, 13.5%). The most common etiology for women and men was breast (102, 30.8%) and lung (67, 36.2%), respectively. More common origins involving peritoneal fluid were gastrointestinal (158, 35.8%) and gynecologic (156, 35.4%) tracts, and breast (46, 10.4%). The most common etiology for women and men was Mullerian (156, 55.5%) and gastrointestinal tract (94, 68.6%), respectively. Most common origins involving the pericardial fluid were breast (20, 37.7%) and lung (17, 29.8%). Breast and lung were the most common etiology for women (20, 57.1%) and men (8, 44.4%), respectively.

CONCLUSIONS

Breast and lung remain to be the most common origin of both malignant pleural and pericardial effusion for women and men, respectively. The most common origin involving peritoneal effusion is Mullerian for women and gastrointestinal tract for men.