A comparative study of conventional cytology and cell block method in the diagnosis of pleural effusion

Rapid on-site evaluation and cell blocks: getting the most from the least invasive method in cytopathology

INTRODUCTION

Fine needle aspiration cytology (FNAC) sampling is a minimally invasive procedure done to identify the pathology behind superficial and deep-seated lesions. Rapid on-site evaluation (ROSE) can be an adjunct to the FNACs. Our study aimed to identify the role of ROSE in diagnostic adequacy and to check the benefit of cell block (CB)/cell buttons prepared from the ROSE samples.

MATERIAL AND METHODS

A prospective study was conducted where all patients referred for FNAC were included. ROSE using 1% aqueous toluidine blue stain and CB/cell button preparations were done for the identification of various cytological lesions.

RESULTS

Among 600 cases included in the study most common age group was third and fourth decades with a mean age of 41.6 years and M: F ratio of 1:1.7. Ultrasound-guided procedures were done in 20% of cases. CB preparation was available in 14% of cases. Most CBs were from the cases wherein ROSE was performed 81% (77 out of 86), with CB helping in making an accurate diagnosis in 17% of cases. Lymph nodes 26%, and thyroid 23% were the most common sites for sampling with the highest number of repeat procedures from non-ROSE cases (14%). The non-diagnostic rate for non-ROSE cases was 7.7% (23/300) even after the repeat procedures as compared to 1.3% (4/300) for ROSE. Three slides on average were consumed in ROSE-performed procedures, as compared to an average of 5 slides in non-ROSE. The average turnaround time was 1.7 days for non-ROSE cases and 1.05 for ROSE cases respectively. Cyto-histopathological correlation was available in 40% of cases with a sensitivity of 98.1%, specificity of 96.7%, positive predictive value of 90%, negative predictive value of 99.4%, and diagnostic accuracy of 97%. The correlation of CB, number of slides consumed, and turnaround time among the 2 groups were statistically significant (P value < 0.001).

CONCLUSIONS

ROSE is a method used to assess material aspirated at the time of FNAC procedures to determine the adequacy and to an extent to identify whether the lesion is neoplastic or non-neoplastic. CBs have helped in increasing diagnostic accuracy apart from the fact that the paraffin-embedded tissue material can be used for further studies.

Beyond diagnosis: a narrative review of the evolving therapeutic role of medical thoracoscopy in the management of pleural diseases

Background and Objective

Medical thoracoscopy (MT) is an endoscopic technique performed by interventional pulmonologists with a favorable safety profile and few contraindications, providing diagnostic and therapeutic intervention in a single sitting. This narrative review was designed to summarize the therapeutic role of MT based on the latest results from the available literature.

Methods

Pertinent literature published in English, relative to human studies, between 2010-2022 was searched in Medline/PubMed and Cochrane databases. Publications regarded as relevant were considered for inclusion in this review; additional references were added based on the authors' knowledge and judgment. The review considered population studies, meta-analyses, case series, and case reports.

Key Content and Findings

MT has mostly been described and is currently used globally in the diagnostic approach to exudative pleural effusion of undetermined origin. Carefully evaluating the literature, it is clear that there is initial evidence to support the use of MT in the therapeutic approach of malignant pleural effusion, pneumothorax, empyema, and less frequently hemothorax and foreign body retrieval.

Conclusions

MT is an effective procedure for treating the clinical entities presented in this document; it must be carried out in selected patients, managed in centers with high procedural expertise. Further evidence is needed to assess the optimal indications and appropriate patients' profiles for therapeutic MT. The endpoints of length of hospital stay, surgical referral, complications and mortality will have to be considered in future studies to validate it as a therapeutic intervention to be applied globally.

Diagnostic analysis of pleural fluid cell blocks using relevant immunohistochemical markers in clinically suspicious cases of malignancy

Objective

Thoracocentesis is a less invasive and expensive procedure than pleural biopsy, enabling sample collection for cytological evaluation. Cell blocks prepared from these samples provide histopathological diagnoses; further, immunohistochemistry (IHC) can be performed for subtyping malignancies, guiding the clinician in choosing the appropriate treatment modality for the patient. We aimed to determine the various histological subtypes of malignancies using cell block IHC and compare the cell block and conventional cytology methods for diagnosing malignant pleural effusion.

Material and Methods

All pleural fluid samples from the clinically suspicious cases of malignancy collected at the Department of Pathology, Government Medical College Kottayam, India, during 18 months, except duplicate and inadequate samples, were included in this prospective observational study. IHC was performed on cell blocks that were positive for malignancy.

Results

This study analyzed 630 samples, of which 121 cell blocks demonstrated the presence of malignancy. Overall, 80%, 13%, and 7% of cases were negative, suspicious, and positive for malignancy based on conventional cytology, and 81%, 0%, and 19% were negative, suspicious, and positive for malignancy based on cell blocks, respectively. Among all malignancies, adenocarcinomas from the lung (56%) were the most common, followed by adenocarcinomas from the breast (6%), squamous cell carcinomas (5%), and adenocarcinomas from the ovary (3%). Cell blocks helped detect more malignancies (19%) than conventional cytology (7%), despite a moderate agreement between both methods.

Conclusion

Adenocarcinomas were the most common cause of malignant pleural effusions, and the most frequent site of origin was the lungs. Cell blocks helped diagnose more malignancies than conventional cytology.

Quality of cell blocks prepared from residual pleural effusion and bronchial washing samples for immunocytochemistry

INTRODUCTION

Cell blocks (CBs) enable the long-term preservation of cytological samples. The aim of this study was to analyse the quality of CBs prepared from leftover fluid from lung adenocarcinoma pleural effusion samples and residual bronchial washing sediment for immunocytochemistry.

METHODS

The residual part of 455 lung adenocarcinoma pleural effusion samples and sediment from 384 bronchial washing samples were used to prepare CBs following the agarose method. The quality of CBs was evaluated based on the quantity of malignant cells in haematoxylin and eosin-stained slides and interpreted as optimal or insufficient for immunocytochemistry. Immunocytochemistry on CBs was performed using the Dako EnVision™ FLEX detection visualisation system. The CB results for TTF-1, ALK, and PD-L1 immunocytochemistry were compared with the corresponding cytological smears.

RESULTS

Among all CBs, 202 (44.4%) from leftover pleural effusion fluid and 85 (22.1%) from residual bronchial washing sediment had an optimal number of lung adenocarcinoma cells. Eight pleural effusion CBs were stained for TTF-1. Four pleural effusion and two bronchial washing CBs were stained for ALK and PD-L1. All tested pleural effusion CBs were confirmed positive for TTF-1 and negative for ALK. The PD-L1 tumour proportion score (TPS) was ≥ 50% in two pleural effusions. ALK was confirmed negative in bronchial washing CBs. One bronchial washing CB was interpreted as PD-L1-negative while the corresponding smear was positive (TPS ≥1%; 2%).

CONCLUSION

The CB results of TTF-1, ALK, and PD-L1 corresponded to the findings for the smears. The inclusion of CBs prepared from leftover fluid from pleural effusion samples and residual bronchial washing sediment in routine cytological practice could provide a source of high-quality material for immunocytochemistry in addition to smears and cytospins.

Sensitivity and complications of thoracentesis and thoracoscopy: a meta-analysis

BACKGROUND

Thoracentesis and thoracoscopy are used to diagnose malignant pleural effusions (MPE). Data on how sensitivity varies with tumour type is limited.

METHODS

Systematic review using PubMed was performed through August 2020 to determine the sensitivity of thoracentesis and thoracoscopy for MPE secondary to malignancy, by cancer type, and complication rates. Tests to identify sources of heterogeneity were performed. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 and National Institutes of Health quality assessment tools. Publication bias was tested using funnel plots.

RESULTS

Meta-analyses for sensitivity of thoracentesis for MPE secondary to malignancy, mesothelioma and lung and breast cancer included 29, eight, 12 and nine studies, respectively. Pooled sensitivities were 0.643 (95% CI 0.592-0.692), 0.451 (95% CI 0.249-0.661), 0.738 (95% CI 0.659-0.836) and 0.820 (95% CI 0.700-0.917), respectively. For sensitivity of thoracoscopy for MPE secondary to malignancy and mesothelioma, 41 and 15 studies were included, respectively. Pooled sensitivities were 0.929 (95% CI 0.905-0.95) and 0.915 (95% CI 0.871-0.952), respectively. Pooled complication rates of thoracentesis and thoracoscopy were 0.041 (95% CI 0.025-0.051) and 0.040 (95% CI 0.029-0.052), respectively. Heterogeneity was significant for all meta-analyses. Funnel plots were asymmetric.

INTERPRETATION

Sensitivity of thoracentesis varied significantly per cancer type. Pooled complication rates were low. Awareness of how sensitivity of thoracentesis changes across cancers can improve decision-making when MPE is suspected.

Handling and standardization of EBUS needle aspiration in NSCLC patients: The value of the cell block, a monoinstitutional experience

BACKGROUND

Lung cancer is the main cause of cancer-related death worldwide, and 85% of all lung tumors are non-small cell lung cancers (NSCLC). More than 60% of all lung tumors are diagnosed at an advanced stage, leading to poor prognosis. Given the growing demand for NSCLC profiling for selection of the most appropriate therapy, the acquisition of adequate tumor samples has become increasingly crucial, mostly in advanced NSCLC patients due to old age and/or comorbidities. Being a mini-invasive sampling technique, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) represents a valuable alternative to traditional transthoracic or surgical sampling in these patients, and perfoming cell block (CB) could be crucial to maximize the potential biological information. The aim of this study is to describe a monoinstitutional interprofessional experience in handling EBUS-TBNA and CB in 464 patients.

METHODS

We retrospectively collected all the consecutive CBs obtained from EBUS TBNA performed between 2014 and 2021 on the lung lesions or mediastinal lymph nodes. All the CBs were handled in a standardized method.

RESULTS

A total of 95.5% (448/464 samples) of adequacy for site and 92.6% (430/464) of adequacy for diagnosis were observed. Moreover, in the adenocarcinoma histotype, ALK, ROS1 and tumor proportion score (TPS) PD-L1 assessment by IHC was possible in 96% (140/146) of cases, and molecular profile was obtained in 93.8% (137/146) of cases. In the squamous cell carcinoma histotype, TPS PD-L1 assessment was possible in 81% (13/16) of cases. All four CB results obtained from carcinoma NOS were adequate for ALK, ROS1 and PD-L1 assessment and molecular profiling. All 39 metastatic samples from extra-pulmonary primary were adequate for immunohistochemical characterization and molecular profiling. Finally, reporting of the tumor sample adequacy to the clinicians took a median time of about 30 h (range: 24-80 h).

CONCLUSION

Careful cytological smear management together with the handling and standardization of CB obtained from EBUS-TBNA could represent an effective method to increase the adequacy of the tumor specimen for both diagnosis and molecular profile.

Malignant pleural disease: a pragmatic guide to diagnosis

PURPOSE OF REVIEW

The diagnosis of malignant pleural disease is important in the care of patients with cancer. However, a one-size-fits-all approach to diagnosis may lead to delays in care as the sensitivity of each biopsy modality varies and can be dependent on the tumor type. We review current literature on pleural biopsy techniques and propose a diagnostic algorithm for suspected malignant pleural disease.

RECENT FINDINGS

Recent literature has shown that the sensitivity of pleural fluid cytology varies based on tumor type resulting in a limited value of repeated thoracenteses in many cases. Furthermore, the ability to test for molecular biomarkers on pleural fluid samples has contributed to the recommendations to send large volumes of pleural fluid for analysis. Studies have also supported the consideration of medical thoracoscopy earlier in the diagnostic work-up of malignant pleural disease.

SUMMARY

The decision to repeat a diagnostic thoracentesis when suspecting malignant pleural effusions should take into account the primary tumor type. Open pleural biopsy with medical thoracoscopy has been shown to be a relatively safe diagnostic modality with high sensitivity and should be considered in patients with a nondiagnostic thoracentesis.

Echogenic swirling pattern, carcinoembryonic antigen, and lactate dehydrogenase in the diagnosis of malignant pleural effusion

The echogenic swirling pattern has a role in predicting malignant pleural effusion (MPE). However, its predictive ability is suboptimal, and its clinical utility remains to be defined. The aim of this study was to assess the diagnostic potential of the echogenic swirling pattern combined with pleural carcinoembryonic antigen (CEA) and routine laboratory tests of pleural effusion in MPE. The 80 consecutive patients with underlying malignancy and pleural effusions were recruited. All patients underwent one diagnostic thoracentesis with a cytologic examination of pleural fluid. Our study showed that the sensitivity of echogenic swirling patterns in MPE diagnosis was 67.7%, specificity was 72.2%, positive predictive value (PPV) was 89.4%, and negative predictive value (NPV) was 39.4%. Both CEA and lactate dehydrogenase (LDH) had acceptable sensitivity (71.0% and 60.7%) and specificity (72.2% and 77.8%). Combining the echogenic swirling pattern, pleural CEA, and pleural LDH, the highest sensitivity (95.2%) with a good PPV (86.8) was reached. In this clinical study, we found that combining the echogenic swirling pattern, pleural CEA, and pleural LDH had a higher sensitivity and a high positive predictive value for the diagnosis of MPE. This combination is a potentially suitable method for MPE screening in cancer patients with pleural effusions.

Development and Validation of a Scoring System for Early Diagnosis of Malignant Pleural Effusion Based on a Nomogram

Background

The diagnostic value of clinical and laboratory features to differentiate between malignant pleural effusion (MPE) and benign pleural effusion (BPE) has not yet been established.

Objectives

The present study aimed to develop and validate the diagnostic accuracy of a scoring system based on a nomogram to distinguish MPE from BPE.

Methods

A total of 1,239 eligible patients with PE were recruited in this study and randomly divided into a training set and an internal validation set at a ratio of 7:3. Logistic regression analysis was performed in the training set, and a nomogram was developed using selected predictors. The diagnostic accuracy of an innovative scoring system based on the nomogram was established and validated in the training, internal validation, and external validation sets (n = 217). The discriminatory power and the calibration and clinical values of the prediction model were evaluated.

Results

Seven variables [effusion carcinoembryonic antigen (CEA), effusion adenosine deaminase (ADA), erythrocyte sedimentation rate (ESR), PE/serum CEA ratio (CEA ratio), effusion carbohydrate antigen 19-9 (CA19-9), effusion cytokeratin 19 fragment (CYFRA 21-1), and serum lactate dehydrogenase (LDH)/effusion ADA ratio (cancer ratio, CR)] were validated and used to develop a nomogram. The prediction model showed both good discrimination and calibration capabilities for all sets. A scoring system was established based on the nomogram scores to distinguish MPE from BPE. The scoring system showed favorable diagnostic performance in the training set [area under the curve (AUC) = 0.955, 95% confidence interval (CI) = 0.942-0.968], the internal validation set (AUC = 0.952, 95% CI = 0.932-0.973), and the external validation set (AUC = 0.973, 95% CI = 0.956-0.990). In addition, the scoring system achieved satisfactory discriminative abilities at separating lung cancer-associated MPE from tuberculous pleurisy effusion (TPE) in the combined training and validation sets.

Conclusions

The present study developed and validated a scoring system based on seven parameters. The scoring system exhibited a reliable diagnostic performance in distinguishing MPE from BPE and might guide clinical decision-making.

Cytologic Investigations for the Diagnosis of Malignant Pleural Effusion in Non-small Cell Lung Cancer: State-of-the-art Review for Pulmonologists

Lung cancer is the current leading cause of cancer-related deaths worldwide, and malignant pleural effusion, an indicator of the advanced stage of this disease, portends a poor prognosis. Thus, making an accurate diagnosis of malignant pleural effusion is of paramount importance. During the past decade, the prognosis of patients with advanced non-small cell lung cancer has improved substantially, especially in those treated with targeted therapy and immunotherapy. The use of pleural fluid cytology should not only provide diagnoses but also aid in the selection of targeted therapies, especially when obtaining a histologic specimen is too difficult. In this evidence-based review, we address the importance of pleural fluid cytology in non-small cell lung cancer patients, from making the diagnosis to making treatment-related decisions when only pleural fluid is available.

ALDH1 and SALL4 Expression in Cell Block Samples from Patients with Lung Adenocarcinoma and Malignant Pleural Effusion

Malignant pleural effusion (MPE) can accompany advanced lung adenocarcinoma. Recent studies suggest that MPE could contain a heterogeneous subpopulation of cells with stem-like properties, such as tumorigenicity and self-renewal, indicating that they could be the source of metastasis. Although previous studies analyzed the correlation between cancer stem cell (CSC) marker expression and clinical outcomes using lung cancer tissues, investigations regarding the association of MPE with CSC marker expression are limited. We performed immunohistochemistry to examine the expression of aldehyde dehydrogenase 1 (ALDH1) and Sal-like 4 (SALL4) in 46 cell block samples of MPE from patients with lung adenocarcinoma. ALDH1-positive and SALL4-positive cancer cells in MPE were detected in 30 (65.2%) and 21 samples (45.7%), respectively. Cluster formation was detected in 26 samples (56.5%). The number of clusters was significantly higher in ALDH1-positive/SALL4-negative samples. SALL4 expression was inversely correlated with the cluster ratio (r = −0.356) and positively associated with the Ki-67 index (r = 0.326), suggesting that MPE cells with high SALL4 expression comprised the proliferative subpopulation. In conclusion, we demonstrated that MPE contains an ALDH1-positive/SALL4-negative subpopulation exhibiting cluster formation and a SALL4-positive proliferative subpopulation.

Architectural aspects of cell-blocks as small biopsies

Cell-block preparations have become an essential part of integrated cytology diagnosis. They are essentially microbiopsies that are formalin fixed and embedded in paraffin. This has become more prevalent with greater sample procurement due to the advent of newer biopsy techniques and needles. Cell-blocks allow retrieval of small tissue fragments from cytology specimens that sometimes cannot be processed by alternate cytologic techniques. They represent concentrated, cell-enriched preparations that provide cytologists with the opportunity to evaluate cellular architecture, as well as to perform ancillary testing. A cell-block compatible sample may thus obviate the need for a more invasive procedure such as a tissue biopsy. Microscopic examination of cell-blocks is quick, avoids obscuring material, permits cells to be evaluated in one focal plane, and allows the histologic architecture such as glandular differentiation, papillary formations, and sometimes invasion to be easily identified. This new era of “cytohistology” accordingly requires practicing cytologists to become more familiar with histopathology. This review article discusses the benefit of various architectural patterns identifiable in cell-blocks employed as an adjunct to Pap tests, exfoliative fluid specimens, and fine-needle aspirations.

Value of Cancer Ratio plus and Cancer Ratio Formulation in Distinguishing Malignant Pleural Effusion from Tuberculosis and Parapneumonic Effusion

Background

The aim of our study is to determine the clinical availability accessibility of cancer ratio and cancer ratio plus formulations, previously validated and reported to have clinical value in distinguishing malignant pleural effusion from tuberculosis pleurisy and parapneumonic effusion.

Materials and Methods

Retrospective study of patients hospitalized with Malignant Pleural Effusion (MPE), tuberculosis (TPE) and pararapneumonic effusion (PPE) between 2009 and 2018.

Results

Totally 232 patients, 101(43.5 %) having MPE, 86 (37.1 %) having PPE and 45 (19.4 %) TPE were examined. When compared with each other, "serum LDH / PS Lymphocyte %", "Cancer ratıo" and "Cancer ratıo plus" values were statistically different between the groups (p = 0.021, p <0.001 and p = 0.015, respectively). In multivariate logistic regression analysis, cancer ratio, serum LDH: pleural fluid lymphocyte count ratio was in positive correlation with MPE. The sensitivity and specificity of "cancer ratio", "cancer ratio plus" and "ratio of serum LDH: pleural fluid lymphocyte count" were 84.2 % (95% CI 75.6- 90.7) and 52.7 (95% CI 43.8- 61.5), and 82.2 % (95% CI 73.3- 89.1) and 45.8 (95%CI 37.1- 54.7), 53.5% (95% CI 43.3- 63.5) and 67.2% (95% CI 0.68-0.94) at the cut-off level of >14.25, >28.7, and >636, respectively. When considering only MPE and TPE patients, the specificity of cancer ratıo and cancer ratıo plus increased.

Conclusion

The cancer ratio plus rate (the ratio of "cancer ratio"formulation to the percentage of differential pleural lymphocyte count) was almost the same as the cancer ratio in separating the malignant pleural effusion from the TPE and PPE, while it has better specificity only in differentiating malignant effusions from tuberculosis effusions.

Role of cancer ratio and other new parameters in the differential diagnosis of malignant pleural effusion

OBJECTIVES

We compared the diagnostic potential of cancer ratio (CR, serum lactate dehydrogenase [LDH]/pleural fluid adenosine deaminase [pfADA]), cancer ratio plus (CR plus, cancer ratio/pleural lymphocyte percentage), and age/pfADA ratio with pfADA in malignant pleural effusion.

METHODS

Data from 100 patients with malignant pleural effusion (MPE) and 119 patients with tuberculous pleural effusion (TPE) were retrospectively collected. PfADA, age/pfADA ratio, CR, and CR plus were compared between patients with MPE and those with TPE in two age groups (≤50 and >50 years). The best cut-off value was determined, and the diagnostic performance was evaluated according to the receiver operating characteristic curve.

RESULTS

PfADA was statistically significantly lower while age/pfADA ratio, CR, and CR plus were significantly higher in the MPE group than in the TPE group in both age groups (p<0.05). For patients aged ≤50 years, the differential diagnostic value of pfADA for MPE was better than those of age/pfADA ratio, CR, and CR plus. At a cut-off value of 13.0 U/L, the sensitivity, specificity, and accuracy were 88.9%, 100.0%, and 98.9%, respectively. For patients aged >50 years, the diagnostic performance of CR plus was superior to those of pfADA, age/pfADA ratio, and CR. At a cut-off value of 22.6, the sensitivity, specificity, and accuracy of CR plus for the diagnosis of MPE were 86.8%, 84.6%, and 86.2%, respectively.

CONCLUSIONS

The best parameter for diagnosing MPE was different for patients aged ≤50 years and >50 years. For patients aged >50 years, CR plus was a good parameter for the differential diagnosis of MPE. For patients aged ≤50 years, pfADA was better.

Diagnosis of Hodgkin Lymphoma from Cell Block: A Reliable and Helpful Tool in "Selected" Diagnostic Practice

Background: The diagnosis of lymphoma requires surgical specimens to perform morphological evaluation, immunohistochemical and molecular analyses. Ultrasound-guided fine needle aspiration may represent an appropriate first approach to obtain cytological samples in impalpable lesions and/or in patients unsuitable for surgical procedures. Although cytology has intrinsic limitations, the cell block method may increase the possibility of achieving an accurate diagnosis. Methods: We retrospectively selected a total of 47 ultrasound-guided fine needle aspiration and drainage samples taken from patients with effusion and deep-seated lesions which are clinically suspicious in terms of malignancy. Results: In 27 cases, both cell block and conventional cytology were performed: 21/27 cell blocks were adequate for the diagnosis of lymphoma and suitable for immunocytochemistry and molecular analyses vs. 12/20 samples to which only conventional cytology was applied. Moreover, in five patients we were able to make a diagnosis of Hodgkin lymphoma with the cell block (CB) technique. Conclusions: Contrary to conventional cytology, the cell block method may allow immunocytochemistry and molecular studies providing useful information for the diagnosis and subtypization of lymphoma in patients unsuitable for surgical procedure or with deep-seated lesions or extra-nodal diseases; additionally, it is a daily, simple and helpful approach. Moreover, we describe the usefulness of cell blocks in the diagnosis of Hodgkin lymphoma.

Development and validation of a novel scoring system developed from a nomogram to identify malignant pleural effusion

BACKGROUND

This study aimed to establish and validate a novel scoring system based on a nomogram for the differential diagnosis of malignant pleural effusion (MPE) and benign pleural effusion (BPE).

METHODS

Patients with PE and confirmed aetiology who underwent diagnostic thoracentesis were included in this study. One retrospective set (N = 1261) was used to develop and internally validate the predictive model. The clinical, radiological and laboratory features were collected and subjected to logistic regression analyses. The primary predictive model was displayed as a nomogram and then modified into a novel scoring system, which was externally validated in an independent set (N = 172).

FINDINGS

The novel scoring system was composed of fever (3 points), erythrocyte sedimentation rate (4 points), effusion adenosine deaminase (7 points), serum carcinoembryonic antigen (CEA) (4 points), effusion CEA (10 points) and effusion/serum CEA (8 points). With a cutoff value of 15 points, the area under the curve, specificity and sensitivity for identifying MPE were 0.913, 89.10%, and 82.63%, respectively, in the training set, 0.922, 93.48%, 81.51%, respectively, in the internal validation set and 0.912, 87.61%, 81.36%, respectively, in the external validation set. Moreover, this scoring system was exclusively applied to distinguish lung cancer with PE from tuberculous pleurisy and showed a favourable diagnostic performance in the training and validation sets.

INTERPRETATION

This novel scoring system was developed from a retrospective study and externally validated in an independent set based on six easily accessible clinical variables, and it exhibited good diagnostic performance for identifying MPE.

FUNDING

NFSC grants (no. 81572942, no. 81800094).

Validation of Calprotectin As a Novel Biomarker For The Diagnosis of Pleural Effusion: a Multicentre Trial

Discriminating between malignant pleural effusion (MPE) and benign pleural effusion (BPE) remains difficult. Thus, novel and efficient biomarkers are required for the diagnosis of pleural effusion (PE). The aim of this study was to validate calprotectin as a diagnostic biomarker of PE in clinical settings. A total of 425 patients were recruited, and the pleural fluid samples collected had BPE in 223 cases (53.7%) or MPE in 137 patients (33%). The samples were all analysed following the same previously validated clinical laboratory protocols and methodology. Calprotectin levels ranged from 772.48 to 3,163.8 ng/mL (median: 1,939 ng/mL) in MPE, and 3,216-24,000 ng/mL in BPE (median: 9,209 ng/mL; p < 0.01), with an area under the curve of 0.848 [95% CI: 0.810-0.886]. For a cut-off value of ≤ 6,233.2 ng/mL, we found 96% sensitivity and 60% specificity, with a negative and positive predictive value, and negative and positive likelihood ratios of 96%, 57%, 0.06, and 2.4, respectively. Multivariate analysis showed that low calprotectin levels was a better discriminator of PE than any other variable [OR 28.76 (p < 0.0001)]. Our results confirm that calprotectin is a new and useful diagnostic biomarker in patients with PE of uncertain aetiology which has potential applications in clinical practice because it may be a good complement to cytological methods.

Micronucleus and Its Significance in Effusion Fluids

Background:

Micronucleus (MN) is an extranuclear body within the cell formed due to failure of incorporation of whole chromosomes or their fragments during cell division. MN scoring can be done to identify malignant effusions.

Aims:

This study aimed to score micronuclei to distinguish malignant effusion from benign effusions and to correlate MN score with type of malignant effusion.

Methods and Materials:

A retrospective study was conducted on 30 malignant and 30 benign effusions. The number of micronucleated cells per 1,000 cells was counted in effusion smears stained with Papanicolaou stain under oil immersion (1,000×).

Results:

The mean MN score in malignant effusions was 3.77 with standard deviation (SD) of 2.13. The mean MN score in benign effusions was 0.50 with SD of 0.57. The difference in MN score between malignant and benign effusions is statistically significant (P < 0.001). A cut-off MN score of 6.5 was seen to distinguish malignant and benign effusions with 100% specificity and 100% sensitivity in this study.

Conclusions:

MN score is higher in malignant effusions when compared with benign effusions. This can be used to differentiate malignant effusions from benign effusions in low resource setting.

Diagnostic accuracy of cancer ratio for malignant pleural effusion: a systematic review and meta-analysis

Background

Several studies have investigated the diagnostic accuracy of serum lactate dehydrogenase (LDH) to pleural fluid adenosine deaminase ratio (cancer ratio, CR) for malignant pleural effusion (MPE), but the results were various. Therefore, we performed this systematic review and meta-analysis to ascertain the diagnostic accuracy of CR for MPE.

Methods

The PubMed and EMBASE databases were searched up to 7 June, 2019 to identify publications concerning diagnostic accuracy of CR for MPE. The sensitivities and specificities of CR in included studies were pooled with a bivariate model. A summary receiver operating characteristic (sROC) curve was used to estimate the global diagnostic accuracy of CR. Quality of the included studies was assessed with the revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2).

Results

Finally, five studies with 596 MPE patients and 863 benign pleural effusion (BPE) patients were included in this systematic review and meta-analysis. The pooled sensitivity and specificity of CR were 0.97 (95% CI: 0.92-0.99) and 0.89 (0.69-0.97), respectively. The area under sROC curve was 0.98 (95% CI: 0.97-0.99). The major design weaknesses of the included studies were patients selection and partial verification bias.

Conclusions

CR has high diagnostic accuracy for MPE. Considering the design weaknesses of available studies, further studies with rigorous design are needed to further validate the findings of this meta-analysis.

A Study Investigating Markers in PLeural Effusion (SIMPLE): a prospective and double-blind diagnostic study

INTRODUCTION

Serum and fluid laboratory markers are valuable for exploring the aetiologies of pleural effusion (PE) because of their relative non-invasiveness, low cost, objective result and short turnaround time. The diagnostic accuracy of these potential markers needs to be rigorously evaluated before their widespread application in clinical practice. Here, we plan to perform a Study Investigating Markers in PLeural Effusion (SIMPLE).

METHODS AND ANALYSIS

This is a prospective and double-blind clinical trial which is being performed at the Affiliated Hospital of Inner Mongolia Medical University, China. Adult patients admitted for the evaluation of aetiology of PE from September 2018 to July 2021 will be enrolled after informed consent. Pleural fluid and serum specimens will be collected and stored at -80°C for the laboratory analysis. The final diagnosis will be concurred with further imaging, microbiology, cytology and biopsy if needed. The results of investigated laboratory markers will be unknown to the clinicians who will make diagnosis and the clinical diagnoses will be unknown to the laboratory technicians who will determine markers. The diagnostic accuracy of investigated markers will be assessed using receiver operating characteristics (ROC) curve analysis, multivariable logistic regression model, decision curve analysis (DCA), net reclassification index (NRI) and integrated discriminatory index (IDI).

ETHICS AND DISSEMINATION

The study is approved by the Ethic Committee of the Affiliated Hospital of Inner Mongolia Medical University (NO: 2018011). The results of SIMPLE will be submitted to international scientific peer-reviewed journals or conferences in laboratory medicine or respiratory medicine, thoracic diseases.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR1800017449); Pre-results.

Contribution of Cell Block Obtained by Thoracentesis in the Diagnosis of Malignant Pleural Effusion

Aim

The aim of this study wass to compare the cytological features of pleural exudative fluids by conventional smear (CS) method and cell block (CB) method and also to assess the utility of the combined approach for cytodiagnosis of these effusions.

Materials and Methods

In all, 113 pleural exudative fluid samples were subjected to evaluation by both CS and CB methods over a period of 2 years. Cellularity, architecture patterns, morphological features, and yield for malignancy were compared, using the two methods. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosis of malignancy were calculated for both the methods, using histology as a gold standard.

Results

CB method provided higher cellularity, better architectural patterns, and additional yield for malignancy when compared with CS method. For 22 (40%) patients, histologic subtype was determined with CB especially for adenocarcinoma. The sensitivity, specificity, positive, and negative predictive values of cytology and CB were 48%, 100%, 100%, 67.8% and 59.2%, 100%, 100%, 72.8%, respectively.

Conclusion

CB technique definitively increased detection of malignancy in pleural fluid effusion when used as an adjunct to CSs. Also, CB provides material suitable for molecular genetic analysis for targeted therapies especially in the treatment of adenocarcinoma.

An uncommon cause of pleural effusion

Pleural disease is a common respiratory condition affecting ∼3000 people per million population annually [1]. Pleural effusion has multiple underlying aetiological conditions and therefore requires a systematic assessment to reach a final diagnosis. Despite detailed evaluation, there may be situations, where the aetiology of a pleural effusion remains unknown [2]. Various experts have suggested a step-wise approach in the management of these undiagnosed pleural effusions [3]. The role of detailed history, proper clinical examination and appropriate investigations, including computed tomography (CT) of chest and pleural biopsy, in an attempt to establish the correct cause of pleural effusion cannot be overemphasised. We present an interesting case of pleural effusion that was managed at our institute.

Pleural effusions are associated with various aetiologies: systematic evaluation is needed to reach a correct diagnosis. In 20% of cases the aetiology of exudative pleural effusion is elusive and pleural biopsy is required to reach a diagnosis.http://bit.ly/2HyZGVZ

Investigating unilateral pleural effusions: the role of cytology

The vast majority of undiagnosed unilateral pleural effusions have fluid sent for cytological analysis. Despite widespread use, there is uncertainty about its sensitivity to diagnose malignant pleural effusions (MPEs). Our aim was to ascertain the utility of cytology using a large prospective cohort.Consecutive patients presenting with an undiagnosed unilateral pleural effusion were recruited to this UK-based study. All had pleural fluid sent for cytological analysis. Cytological sensitivity was based on the final diagnosis at 12 months, confirmed by two consultants.Over 8 years, 921 patients were recruited, of which 515 had a MPE. Overall sensitivity of fluid cytology to diagnose malignancy was 46% (95% CI 42-58%). There was variation in sensitivity depending on cancer primary, with mesothelioma (6%) and haematological malignancies (40%) being significantly lower than adenocarcinomas (79%). MPEs secondary to ovarian cancer had high pick-up rates (95%). In asbestos-exposed males with exudative effusions, the risk of MPE was 60%, but cytological sensitivity was 11%.This is the largest prospective study of pleural fluid cytology and informs discussions with patients about the likely requirement for investigations following thoracentesis. In patients presenting with a clinical suspicion of mesothelioma, cytological sensitivity is low, so more definitive investigations could be performed sooner.

Diagnostic benefits of the combined use of liquid-based cytology, cell block, and carcinoembryonic antigen immunocytochemistry in malignant pleural effusion

Background

Malignant pleural effusion (MPE) is a common complication of cancer cell metastasis to the pleura. Discrimination between MPE and benign pleural effusion is necessary to design treatment strategies. Cytology is important for the diagnosis of MPE. Carcinoembryonic antigen (CEA) is an epithelial biomarker with a strong staining pattern in adenocarcinomas. Here, the diagnostic performances of liquid-based cytology (LBC), cell block (CB) preparation, and CEA immunostaining for the detection of malignancy in effusion cytology were compared in a large case series.

Methods

In a single institution, 1,014 cytology samples from 862 patients were retrospectively collected and reviewed between January 2013 and November 2015. Ethanol-fixed, paraffin embedded CB of pleural effusions was analyzed by CEA immunostaining. Diagnostic values were compared among LBC, CB, CEA immunostaining, and the combination of two methods.

Results

The sensitivity and specificity of the CB preparation were 94.3% and 98.7%, respectively, compared with 81.3% and 99.4% for LBC preparations, respectively. Combination of LBC and CB increased sensitivity by 98.3%. Although the accuracy of CEA staining itself was moderate (sensitivity, 89.8%), the combined use of CB and CEA tumor marker increased the detection rate of malignancy (sensitivity, 100%; specificity, 100%), compared with that of cytology (LBC or CB) alone.

Conclusions

The sensitivity and specificity for the diagnosis of MPE could be improved by integrating the CB and CEA staining into LBC in routine clinical practice to improve diagnostic accuracy.

Lung cancer staging: a concise update

Diagnosis and clinical staging of lung cancer are fundamental to planning therapy. The techniques for clinical staging, i.e anatomic and metabolic imaging, endoscopies and minimally invasive surgical procedures, should be performed sequentially and with an increasing degree of invasiveness. Intraoperative staging, assessing the magnitude of the primary tumour, the involved structures, and the loco-regional lymphatic spread by means of systematic nodal dissection, is essential in order to achieve a complete resection. In resected tumours, pathological staging, with the systematic study of the resected specimens, is the strongest prognostic indicator and is essential to make further decisions on therapy. In the present decade, the guidelines on lung cancer staging of the American College of Chest Physicians and the European Society of Thoracic Surgeons are based on the best available evidence and are widely followed. Recent advances in the classification of the adenocarcinoma of the lung, with the definition of adenocarcinoma in situ, minimally invasive adenocarcinoma and lepidic predominant adenocarcinoma, and the publication of the eighth edition of the tumour, node and metastasis classification of lung cancer, have to be integrated into the staging process. The present review complements the latest guidelines on lung cancer staging by providing an update of all these issues.