Etiology of pleural effusions: analysis of more than 3,000 consecutive thoracenteses

Diagnostic Utility of Pleural C-Reactive Protein and Procalcitonin for Parapneumonic Pleural Effusion: A Head-to-Head Comparison Study

Introduction

The diagnostic utility of pleural fluid C-reactive protein (CRP) and procalcitonin (PCT) for parapneumonic pleural effusion (PPE) is a subject of ongoing investigation. There remains lack studies comparing their diagnostic accuracy in a head-to-head manner. Furthermore, the incremental diagnostic value of their combination over a single marker and the net benefit of them remains unknown.

Methods

This prospective study enrolled participants presenting with undiagnosed pleural effusion, subsequently measuring their pleural levels of CRP and PCT. A diagnostic model that integrated both biomarkers was constructed using logistic regression analysis. The diagnostic performance and net benefit of CRP, PCT, and the composite model were assessed through receiver-operating characteristic (ROC) curve analysis and decision curve analysis (DCA).

Results

The study included 32 PPE patients and 121 patients without PPE. The area under the ROC curve (AUC) for CRP was 0.73 (95% confidence interval [CI]: 0.63-0.83), with a sensitivity of 0.71 (95% CI: 0.55-0.87) and a specificity of 0.68 (95% CI: 0.59-0.77) at a threshold of 10 mg/L. In contrast, the AUC for PCT was 0.58 (95% CI: 0.46-0.69), with sensitivity and specificity rates of 0.50 (95% CI: 0.33-0.67) and 0.65 (95% CI: 0.56-0.74) at a threshold of 0.1 ng/mL, respectively. Notably, the AUC for the diagnostic model was comparable to that of CRP alone at 0.73 (95% CI: 0.63-0.82). DCA showed that applying CRP provided a net clinical benefit, while PCT did not.

Conclusion

Pleural fluid CRP possesses moderate diagnostic capability for PPE, while PCT exhibits limited diagnostic utility. Additionally, the combined application of CRP and PCT does not confer any significant enhancement in diagnostic accuracy over the use of CRP alone.

The diagnostic accuracy of HE4 in the differential diagnosis of pleural effusions

BACKGROUND

Pleural effusions are challenging to diagnose, with approximately 20-50% of malignant effusions not diagnosed by cytology. Human epididymal protein 4 (HE4) may be useful in the differential diagnosis of pleural effusions. In serum, this biomarker shows false-positive results in some benign diseases. The aim of this study was to evaluate the diagnostic utility of HE4 in this setting and to identify false positives.

METHODS

Concentrations of HE4, adenosine deaminase, % polynuclear cells, and C-reactive protein, were determined in 238 pleural fluid samples and the estimated glomerular filtration rate (eGFr) in serum.

RESULTS

HE4 values ​​differed significantly (p < 0.01) between malignant [median (IQR)] [1065 (2085)] pmol/L and benign effusions [699 (589)] pmol/L. HE4 concentrations in gynecological and pulmonary tumors were significantly higher than in other tumors. For a cut-off point of 3050 pmol/L, 22 % sensitivity and 100 % specificity were obtained. In patients with benign disease, significant increases in HE4 were identified only in those with eGFr < 30 mL/min/1.73 m2 [1050(596)] pmol/L, and not in those with eGFr > 30 mL/min/1.73 m2 [597(532)] pmol/L). Two cut-offs were established for maximum specificity, depending on the eGFr: 3050 pmol/L for eGFr < 30 mL/min/1.73 m2 and 1992 pmol/L for eGFr > 30 mL/min/1.73 m2. A sensitivity of 28.5 % was obtained for patients with eGFr > 30 mL/min/1.73 m2 and 36.3 % for patients with eGFr < 30 mL/min/1.73 m2. The sensitivity using a specific cut-off point was 29.7 %.

CONCLUSIONS

The determination of HE4 in pleural fluids demonstrates high specificity and low sensitivity. The use of specific cutoff points that are clinically adjusted improves sensitivity while maintaining maximum specificity.

Influences of age and sex on the diagnostic accuracy of human epididymis secretory protein 4 for malignant pleural effusion

Previous studies have suggested that the presence of human epididymal protein 4 (HE4) in pleural fluid can be used to diagnose malignant pleural effusion (MPE) with moderate accuracy. However, the factors that affect the diagnostic accuracy of HE4 remain unknown. This study aimed to examine how age and sex influence the diagnostic accuracy of HE4. Participants with undiagnosed pleural effusion were prospectively enrolled in two cohorts (Hohhot cohort and Changshu cohort), and the presence of HE4 in their pleural fluid upon admission was determined by an electrochemiluminescence immunoassay. A receiver operating characteristic (ROC) curve with its area under the curve (AUC) was utilized to assess the diagnostic value of HE4 for MPE. Additionally, we conducted subgroup analyses and used a resampling method with different upper age limits to investigate the impacts of age and sex on the diagnostic accuracy of HE4 for MPE. The Hohhot cohort included 86 patients with benign pleural effusions (BPEs) and 66 patients with MPE, whereas the Changshu cohort included 26 patients with MPE and 32 patients with BPE. The diagnostic accuracy of HE4 decreased as age increased in both cohorts. The diagnostic accuracy of HE4 in males did not differ significantly from that in females. Therefore, we conclude that age should be considered when using HE4 in pleural fluid to diagnose MPE.

American Association of Bronchology and Interventional Pulmonology Essential Knowledge in Interventional Pulmonology Series: Selected Topics in Malignant Pleural Disease

The goal of the American Association of Bronchology and Interventional Pulmonology Essential Knowledge in Interventional Pulmonology Series is to provide clinicians with concise, up-to-date reviews of important topics in the field of interventional pulmonology. This 3-year alternating rotation of primary topics will start with a focus on selected topics in malignant pleural disease. In this article, we update the reader on malignant pleural effusion in 3 parts: part 1-diagnosis, focusing on imaging and fluid biomarkers; part 2-management, with review of multimodal approaches, cost considerations, and evolving targeted therapies; and part 3-pleural mesothelioma. These reviews complement the Essential Knowledge in Interventional Pulmonology Lecture Series presented at the 2023 AABIP Annual Conference, available for viewing on the AABIP website (https://aabip.memberclicks.net/essential-knowledge-in-interventional-pulmonology-series).

The Use of "Cancer Ratio" in Differentiating Malignant and Tuberculous Pleural Effusions: Protocol for a Prospective Observational Study

BACKGROUND

Differentiating between tuberculosis and malignancy as the cause of an exudative lymphocyte predominant pleural effusion is difficult due to similarities in the cellular and biochemical characteristics of the pleural fluid in both conditions. Microbiological tests in tubercular pleural effusions have a poor diagnostic yield, and the long turnaround time for results prevents an early diagnosis. The diagnosis of malignant pleural effusion (MPE) is hampered by a variable yield of pleural fluid cytology and closed pleural biopsy and the fact that thoracoscopy may not be readily available or feasible in each patient. A key gap in the existing knowledge is the performance of the serum lactate dehydrogenase to pleural adenosine deaminase ratio (ie, "cancer ratio"; CR) in differentiating between tuberculous and MPE in a high tuberculosis prevalence country like India, although its use has been well established in Western literature. The CR may find a practical application in the community health care settings in low-income countries without ready access to biopsy.

OBJECTIVE

This study aimed to evaluate the CR as a test to differentiate tubercular and malignant etiology in patients with an exudative lymphocyte predominant pleural effusion. Secondary objectives to be assessed include a comparison of CR to pleural fluid carcinoembryonic antigen in MPE and the association of histologic type of lung carcinoma to the CR positivity.

METHODS

This hospital-based, prospective, observational study will include patients admitted with pleural effusion whose pleural fluid reports indicate a lymphocyte-predominant exudate. The ability of the CR to discriminate between tuberculous and MPE will be evaluated as a primary objective of this study. The performance of CR and pleural fluid carcinoembryonic antigen in the diagnosis of MPE will be compared using the receiver operating characteristics and area under the curve for both tests as a secondary objective. The association between a positive CR and histologic type of lung cancer will be analyzed as well.

RESULTS

Data collection began in June 2022. As of March 24, 2024, we have recruited 22 patients. Outcomes of the study are expected at the end of 2024.

CONCLUSIONS

The results of this study will provide an objective basis for the use of CR in differentiating between tuberculosis and malignancy as the cause of an exudative lymphocyte predominant pleural effusion.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56592.

ERS statement on benign pleural effusions in adults

The incidence of non-malignant pleural effusions far outweighs that of malignant pleural effusions and is estimated to be at least 3-fold higher. These so-called benign effusions do not follow a "benign course" in many cases, with mortality rates matching and sometimes exceeding those of malignant pleural effusions. In addition to the impact on patients, healthcare systems are also significantly affected, with recent US epidemiological data demonstrating that 75% of resource allocation for pleural effusion management is spent on non-malignant pleural effusions (excluding empyema). Despite this significant burden of disease, and by existing at the junction of multiple medical specialties, reflecting a heterogenous constellation of medical conditions, non-malignant pleural effusions are rarely the focus of research or the subject of management guidelines. With this European Respiratory Society Task Force, we assembled a multispecialty collaborative across 11 countries and three continents to provide a statement based on systematic searches of the medical literature to highlight evidence in the management of the following clinical areas: a diagnostic approach to transudative effusions, heart failure, hepatic hydrothorax, end-stage renal failure, benign asbestos-related pleural effusion, post-surgical effusion and nonspecific pleuritis.

The diagnostic value of pleural effusion/serum ratio of carcinoembryonic antigen and pleural effusion/serum ratio of interferon-γ in classification of pleural effusion

BACKGROUND

Distinguishing between different types of pleural effusions (PEs) is crucial for clinical diagnosis and treatment. This study evaluates the diagnostic value of carcinoembryonic antigen (CEA) and interferon-gamma (IFN-γ) levels in PE and serum, as well as the PE/serum ratios of these markers, in classifying PE.

METHODS

We retrospectively analyzed 99 patients with PE, categorizing them into malignant pleural effusion (MPE), tuberculous pleural effusion (TPE), and benign PE groups. Levels of CEA and IFN-γ in PE and serum were quantified and their ratios were calculated. Diagnostic performance was assessed using receiver operating characteristic analysis, focusing on the area under the curve (AUC) to determine the efficacy of these biomarkers.

RESULTS

Significantly elevated levels of CEA in PE and serum were observed in the MPE group compared to the benign and TPE groups, with the PE/serum CEA ratio offering substantial diagnostic value (AUCs: PE = 0.843, serum = 0.744). Conversely, IFN-γ levels in PE and serum were markedly higher in the TPE group, demonstrating notable diagnostic accuracy (AUCs: PE = 0.970, serum = 0.917).

CONCLUSION

Both CEA and IFN-γ demonstrate high clinical utility in differentiating between MPE and TPE. The PE/serum ratio of these biomarkers enhances diagnostic accuracy, potentially facilitating earlier and more accurate therapeutic interventions.

Biological and cytological-morphological assessment of tuberculous pleural effusions

AIM

Tuberculosis (TB) came back in the top of causes for infectious disease-related deaths and its pleural involvement is still in the top two extrapulmonary sites. The authors continued their studies on TB pleural effusions (Pl-Effs) with the assessment of biological and cytological variable of pleural fluid (PF), introducing in the investigation algorithm and testing a new tool, the computer-assisted evaluation of cell populations on PF smears.

PATIENTS, MATERIALS AND METHODS

A series of 85 patients with TB pleurisy (PLTB) were selected from a larger group of 322 patients with different types of Pl-Effs. The algorithm of investigation included. clinical variables, biological assays of PF, gross aspects including imagistic variables and PF cytology on May-Grünwald-Giemsa (MGG)-stained smears. All the data obtained were entered into and processed using Microsoft Excel module of the 2019 Microsoft Office Professional software along with the 2014 XLSTAT add-in program for MS Excel. The PF cellularity was assessed qualitatively by a cytologist and quantitatively with in-house software. Continuous variables were compared using Pearson's correlation test, while categorical variables were compared using χ² (chi-squared) test.

RESULTS

Our analysis showed that patients were usually males, aged between 25 and 44 years with Pl-Eff discovered at clinical imagistic examination, almost always one-sided and free in the pleural cavity. Its extension was either moderate or reduced. The PF had a serous citrine appearance in most of the cases, and biological characteristics pleaded for an exudate [high levels of proteins and lactate dehydrogenase (LDH)], with elevated adenosine deaminase (ADA) values and rich in lymphocytes (Ly). The attempt to identify the pathogen in PF was not of much help. Apart from Ly, neutrophils [polymorphonuclear neutrophils (PMNs)] were a rare presence and their amount had only a trend of direct correlation with Ly. The same situation was encountered in the case of mesothelial cells (MCs). The comparison between the qualitative and the quantitative, computer-assisted evaluations of cytological smears showed that the results of the two methods overlapped in less than one third of the cases, although the sensitivity and specificity values as well as the two calculated predictive values of the qualitative method were encouraging.

CONCLUSIONS

The assessment of biological variables and cell populations of the PF are basic tools in the diagnosis of pleural TB. The assessment of PF cell population could be improved by the use of computer-assisted quantitative analysis of the PF smears, which is simple to design, easy to introduce and handle and reliable.

Aetiology of Pleural Effusions in a Large Multicentre Cohort: Variation Between Outpatients and Inpatients

INTRODUCTION

This multi-centre retrospective cohort study aimed to determine whether the cause of an undiagnosed pleural effusion differed depending on if a patient presented as an outpatient or inpatient.

METHODS

A total of 1080 adult patients (556 inpatients and 524 outpatients) presenting primarily with an undiagnosed pleural effusion from 1 January 2021 to 31 December 2022 from four UK hospitals were included.

RESULTS

We found malignant effusions were more common in outpatients compared to inpatients (48.3% vs. 36.0% p < 0.0001). Infection was common in inpatients but uncommon in outpatients (36.2% vs. 5.0% p < 0.0001). Other causes in all patients included heart and/or renal failure (13.1%) and non-specific pleuritis (5.6%). No diagnosis was possible in 11.8% of patients referred.

CONCLUSION

Investigative pathways should vary depending on whether patients present as an inpatient or outpatient.

Apolipoprotein E in patients with undiagnosed pleural effusion: a prospective diagnostic test accuracy study

INTRODUCTION

Pleural effusion is common in clinical practice, and its differential diagnosis remains challenging for clinicians. This study investigates the diagnostic value of apolipoprotein E (apoE) in patients with undetermined pleural effusion.

METHODS

This prospective, double-blind study enrolled 152 patients with undiagnosed pleural effusion. Their pleural fluid apoE levels were measured, and a receiver operating characteristics (ROC) curve was used to evaluate the diagnostic accuracy of apoE. Decision curve analysis (DCA) was used to assess apoE's net benefit. Subgroup analyses were performed to investigate the effect of age on the diagnostic accuracy of apoE.

RESULTS

Among the included participants, 23 had heart failure (HF). HF patients had the lowest apoE level among pleural effusion patients. The area under the curve (AUC) of apoE for HF was 0.79 (95% CI: 0.69-0.89). At the threshold of 40 mg/L, the sensitivity and specificity of apoE were 0.96 (95% CI: 0.87-1.00) and 0.33 (95% CI: 0.25-0.42), respectively. The decision curve for apoE was above reference lines. The AUC of apoE decreased in older patients.

CONCLUSION

Pleural fluid apoE has moderate diagnostic value for HF and has net benefits in patients with undiagnosed pleural effusion. The diagnostic accuracy of apoE decreases with age.

Elusive Unilateral Pleural Effusion: Keys to Clinching the Diagnosis

Unilateral pleural effusions may sometimes be difficult to diagnose. The cause may vary widely, including congestive heart failure, chronic liver and kidney disease, various drugs, and underlying undiagnosed disorders of the lung and pleura. With advancements in chest imaging, new biomarkers, and less invasive methods for obtaining tissue samples, it may be possible to identify the cause of the unilateral pleural effusions whose etiology is unclear. Even reviewing patient history, re-examining pleural fluid, classifying effusions based on Light's criteria, and ruling out pseudoexudates can help understand the cause. We aim to discuss a case of unilateral pleural effusion and, on its backdrop, discuss an approach to elusive unilateral pleural effusion.

Image-Assısted Pleural Needle Biopsy or Medical Thoracoscopy: Which Method for Which Patient? A Randomızed Controlled Trial

BACKGROUND

Image-guided or assisted needle biopsies and the increasing use of medical thoracoscopy (MT) have increased the diagnostic accuracy of pleural diseases significantly. However, no consensus exists regarding which patients with pleural effusion should undergo MT and which patients should undergo image-guided or assisted needle biopsy as the first procedure to ensure greater diagnostic accuracy.

RESEARCH QUESTION

Which biopsy method is more appropriate for which patient to provide the highest diagnostic accuracy in the diagnosis of pleural effusion?

STUDY DESIGN AND METHODS

This prospective, randomized, parallel study included 228 patients with undiagnosed exudative pleural effusion. Patients were divided into two groups based on CT scan findings. Group 1 included patients with pleural effusion only. Group 2 included patients with pleural thickening or lesion in addition to pleural effusion. Patients in each group were assigned randomly to an image-assisted Abrams needle pleural biopsy (IA-ANPB) or MT arm. The diagnostic sensitivity, reliability, and safety were determined for both groups.

RESULTS

The false-negative rate was 30.3% for the IA-ANPB arm and 3.1% for the MT arm in group 1. The same rates were 11.9% for IA-ANPB and 4.7% for MT in group 2. In group 1, the sensitivity for the IA-ANPB arm was 69.7%, and the negative likelihood ratio was 0.30. The same rates for the MT arm were 96.9% and 0.03 (P = .009). In group 2, these values were 88.1% and 0.12 for the IA-ANPB arm and 95.4% and 0.05 for the MT arm (P = .207). The rate of complications between the two biopsy methods was not different (8.5% and 15.8%, respectively; P = .107).

INTERPRETATION

MT showed a high diagnostic success in all patients with pleural fluid. However, IA-ANPB showed similar diagnostic success as MT in patients with pleural effusion and associated pleural thickening or lesions. Therefore, in the latter case, IA-ANPB could be preferable to MT.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT05428891; URL: www.

CLINICALTRIALS

gov.

Diagnostic accuracy and cellular origin of pleural fluid CXCR3 ligands for tuberculous pleural effusion

BACKGROUND

Pleural biomarkers represent potential diagnostic tools for tuberculous pleural effusion (TPE) due to their advantages of low cost, short turnaround time, and less invasiveness. This study evaluated the diagnostic accuracy of two CXCR3 ligands, C-X-C motif chemokine ligand 9 (CXCL9) and CXCL11, for TPE. In addition, we investigated the cellular origins and biological roles of CXCL9 and CXCL11 in the development of TPE.

METHODS

This double-blind study prospectively enrolled patients with undiagnosed pleural effusion from two centers (Hohhot and Changshu) in China. Pleural fluid on admission was obtained and levels of CXCL9 and CXCL11 were measured by an enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate their diagnostic accuracy and net benefit, respectively. THP-1 cell-derived macrophages were treated with Bacillus Calmette-Guérin (BCG), and quantitative real-time PCR (qRT-PCR) and ELISA were used to determine the mRNA and protein levels of CXCL9 and CXCL11. The chemoattractant activities of CXCL9 and CXCL11 for T helper (Th) cells were analyzed by a transwell assay.

RESULTS

One hundred and fifty-three (20 TPEs and 133 non-TPEs) patients were enrolled in the Hohhot Center, and 58 (13 TPEs and 45 non-TPEs) were enrolled in the Changshu Center. In both centers, we observed increased CXCL9 and CXCL11 in TPE patients. The areas under the ROC curves (AUCs) of pleural CXCL9 and CXCL11 in the Hohhot Center were 0.70 (95 % CI: 0.55-0.85) and 0.68 (95 % CI: 0.52-0.84), respectively. In the Changshu Center, the AUCs of CXCL9 and CXCL11 were 0.96 (95 % CI: 0.92-1.00) and 0.97 (95 % CI: 0.94-1.00), respectively. The AUCs of CXCL9 and CXCL11 decreased with the advancement of age. The decision curves of CXCL9 and CXCL11 showed net benefits in both centers. CXCL9 and CXCL11 were upregulated in BCG-treated macrophages. Pleural fluid from TPE and conditioned medium from BCG-treated macrophages were chemotactic for Th cells. Anti-CXCL9 or CXCL11 neutralizing antibodies could partly block the chemotactic activity.

CONCLUSIONS

Pleural CXCL9 and CXCL11 are potential diagnostic markers for TPE, but their diagnostic accuracy is compromised in elderly patients. CXCL9 and CXCL11 can promote the migration of peripheral Th cells, thus representing a therapeutic target for the treatment of TPE.

Re-enforcing High-Risk Acute Pericarditis Requiring Hospital Admission: An Unusual Case of Critical Idiopathic Acute Pericarditis Presenting As Tamponade and Pleuro-Pericardial Complications in a Patient Presenting With Flu-Like Symptoms

Pericarditis is an inflammatory process that affects the pericardium, the fibrous sac surrounding the heart. Acute pericarditis accounts for approximately 0.1% of inpatient admissions and 5% of non-ischemic chest pain visits to the emergency departments (EDs). Most patients who present with acute pericarditis have a benign course and good prognosis. However, a rare percent of the patients develop complicated pericarditis. Examples of complications include pericardiac effusion, cardiac tamponade, constrictive pericarditis, effusive and constrictive pericarditis and, even more rarely, large pleural effusion The occurrence of complicated pericarditis can lead to high morbidity and mortality if not urgently managed in most patients. Our case presents a 60-year-old male that presented to the emergency room with flu-like symptoms. However, the viral panel test was negative. He initially got discharged with supportive care but was brought back to the ED by his wife in a critical, life-threatening state due to pericarditis symptoms complicated by tamponade and shock. His condition required urgent intervention and critical level of care. The patient's course was also complicated by myopericarditis and recurrent bilateral pleural effusions, which required therapeutic interventions. This unique case presents the patient group that develop multiple life-threatening complications of acute pericarditis, including cardiac tamponade and shock, affecting several end organs. This case also highlights clues to the predisposing factors to complications of acute pericarditis. Patients who present with high-risk signs and symptoms indicating poorer prognosis warrant further observation and admission. This will also add to the literature reviews regarding the risk factors associated with development of complicated acute pericarditis. This will also serve as a review of pathophysiology, etiology, current diagnosis and available novel treatment for such patients.

Malignant pleural effusion: current understanding and therapeutic approach

Malignant pleural effusion (MPE) is a common complication of thoracic and extrathoracic malignancies and is associated with high mortality and elevated costs to healthcare systems. Over the last decades the understanding of pathophysiology mechanisms, diagnostic techniques and optimal treatment intervention in MPE have been greatly advanced by recent high-quality research, leading to an ever less invasive diagnostic approach and more personalized management. Despite a number of management options, including talc pleurodesis, indwelling pleural catheters and combinations of the two, treatment for MPE remains symptom directed and centered around drainage strategy. In the next future, because of a better understanding of underlying tumor biology together with more sensitive molecular diagnostic techniques, it is likely that combined diagnostic and therapeutic procedures allowing near total outpatient management of MPE will become popular. This article provides a review of the current advances, new discoveries and future directions in the pathophysiology, diagnosis and management of MPE.

Lung cancer tumor markers in serous effusions and other body fluids

From its onset and during its progression, lung cancer may affect various extrapulmonary structures. These include the serous membranes, the pleura and pericardium, and less frequently the central nervous system, with leptomeningeal involvement. In these cases, fluid accumulates in the serous membranes which may contain substances secreted by the tumor. Measuring the concentrations of these substances can provide useful information for elucidating the origin of the fluid accumulation, either in pleural and pericardial effusions or in cerebrospinal fluid. This paper describes the histological types of lung cancer that most frequently affect the serosa and leptomeninges. It also reviews the literature on tumor markers in different fluids and makes recommendations for their interpretation.

Pleural fluid carbohydrate antigen 72-4 and malignant pleural effusion: a diagnostic test accuracy study

BACKGROUND

The prognosis of malignant pleural effusion (MPE) is poor. A timely and accurate diagnosis is the prerequisite for managing MPE patients. Carbohydrate antigen 72-4 (CA72-4) is a diagnostic tool for MPE.

OBJECTIVE

We aimed to evaluate the diagnostic accuracy of pleural fluid CA72-4 for MPE.

DESIGN

A prospective, preregistered, and double-blind diagnostic test accuracy study.

METHODS

We prospectively enrolled participants with undiagnosed pleural effusions from two centers in China (Hohhot and Changshu). CA72-4 concentration in pleural fluid was measured by electrochemiluminescence. Its diagnostic accuracy for MPE was evaluated by a receiver operating characteristic (ROC) curve. The net benefit of CA72-4 was determined by a decision curve analysis (DCA).

RESULTS

In all, 153 participants were enrolled in the Hohhot cohort, and 58 were enrolled in the Changshu cohort. In both cohorts, MPE patients had significantly higher CA72-4 levels than benign pleural effusion (BPE) patients. At a cutoff value of 8 U/mL, pleural fluid CA72-4 had a sensitivity, specificity, and area under the ROC curve (AUC) of 0.46, 1.00, and 0.79, respectively, in the Hohhot cohort. In the Changshu cohort, CA72-4 had a sensitivity, specificity, and AUC of 0.27, 0.94, and 0.86, respectively. DCA revealed the relatively high net benefit of CA72-4 determination. In patients with negative cytology, the AUC of CA72-4 was 0.67.

CONCLUSION

Pleural fluid CA72-4 helps differentiate MPE and BPE in patients with undiagnosed pleural effusions.

Development and validation of a radiomics nomogram for diagnosis of malignant pleural effusion

OBJECTIVE

We aimed to develop a radiomics nomogram based on computed tomography (CT) scan features and high-throughput radiomics features for diagnosis of malignant pleural effusion (MPE).

METHODS

In this study, 507 eligible patients with PE (207 malignant and 300 benign) were collected retrospectively. Patients were divided into training (n = 355) and validation cohorts (n = 152). Radiomics features were extracted from initial unenhanced CT images. CT scan features of PE were also collected. We used the variance threshold algorithm and least absolute shrinkage and selection operator (LASSO) to select optimal features to build a radiomics model for predicting the nature of PE. Univariate and multivariable logistic regression analyzes were used to identify significant independent factors associated with MPE, which were then included in the radiomics nomogram.

RESULTS

A total of four CT features were retained as significant independent factors, including massive PE, obstructive atelectasis or pneumonia, pleural thickening > 10 mm, and pulmonary nodules and/or masses. The radiomics nomogram constructed from 13 radiomics parameters and four CT features showed good predictive efficacy in training cohort [area under the curve (AUC) = 0.926, 95% CI 0.894, 0.951] and validation cohort (AUC = 0.916, 95% CI 0.860, 0.955). The calibration curve and decision curve analysis showed that the nomogram helped differentiate MPE from benign pleural effusion (BPE) in clinical practice.

CONCLUSION

This study presents a nomogram model incorporating CT scan features and radiomics features to help physicians differentiate MPE from BPE.

A PET-CT score for discriminating malignant from benign pleural effusions

BACKGROUND AND OBJECTIVES

The results of previous PET-CT studies are contradictory for discriminating malignant from benign pleural effusions. We purpose to develop a PET-CT score for differentiating between benign and malignant effusions.

PATIENTS AND METHODS

We conducted a prospective study of consecutive patients with pleural effusions undergoing PET-CT from October 2013 to October 2019 (referral cohort). PET-CT scan features evaluated using the SUV were: linear thickening; nodular thickening; nodules; masses; circumferential thickening; mediastinal and fissural pleural involvement; intrathoracic lymph nodes; pleural loculation; inflammatory consolidation; pleural calcification; cardiomegaly; pericardial effusion; bilateral effusion; lung mass; liver metastasis and other extra-pleural malignancy. The results were validated in an independent prospective cohort from November 2019 to June 2021.

RESULTS

One hundred and ninety-nine patients were enrolled in the referral cohort (91 with malignant effusions and 108 benign). The most useful parameters for the development of a PET-CT score were: nodular pleural thickening, pleural nodules with SUV>7.5, lung mass or extra pleural malignancy (10 points each), mammary lymph node with SUV>4.5 (5 points) and cardiomegaly (-1 point). With a cut-off value of >9 points in the referral cohort, the score established the diagnosis of malignant pleural effusion with sensitivity 87.9%, specificity 90.7%, positive predictive value 88.9%, negative predictive value 89.9%, positive likelihood ratio 7.81 and negative likelihood ratio 0.106. These results were validated in an independent prospective cohort of 75 patients.

CONCLUSIONS

PET-CT score was shown to provide relevant information for the identification of malignant pleural effusion.

Pleural Pustule-a Novel Thoracoscopic Appearance of Pleural Tuberculosis

BACKGROUND

Thoracoscopic pleural biopsy is the gold standard for diagnosing tubercular pleural effusion (TPE). Various thoracoscopic appearances like sago grain nodules, caseous necrosis, and adhesions have been described in TPE. However, none of these have high specificity for diagnosing TPE. In this study we evaluate a novel finding on thoracoscopy, the " Pleural Pustule."

METHODS

This is a retrospective analysis of patients who underwent thoracoscopy for undiagnosed pleural effusion. Visual inspection of the pleura was performed to identify abnormalities. Biopsies were obtained from those areas and sent for histopathology, acid fast bacillus (AFB) smear, culture, and Xpert MTB/Rif assay. Pleural pustule was defined as a pus filled nodule on the pleural surface.

RESULTS

Of the 259 patients included, 92 were diagnosed with TPE. Pleural pustule(s) were identified in 16 patients with TPE. Presence of pleural pustule had a sensitivity, specificity, positive predictive value, and negative predictive value of 17.4%, 100%, 100% and 68.7%, respectively, for diagnosing TPE. Histopathology of pleural pustule demonstrated necrotizing granulomas in all. In patients with pleural pustule, a microbiological diagnosis of tuberculosis was achieved in 93.7% patients (AFB smear, Xpert MTB/Rif assay, and MTB culture positive in 31.3%, 93.7%, and 43.7% cases, respectively). There is a strong association between pleural pustule and positive Xpert MTB/Rif assay ( P =0.002) and microbiologic confirmation of diagnosis ( P =0.017).

CONCLUSION

The presence of pleural pustule on thoracoscopy has a high positive predictive value for TPE. In tuberculosis-endemic countries, this can be considered suggestive for TPE. When identified, a biopsy from the pleural pustule should be performed as it will likely yield a positive microbiologic diagnosis.

Construction of a multi-classified decision tree model for identifying malignant pleural effusion and tuberculous pleural effusion

OBJECTIVE

Pleural effusion (PE) is a common clinical complication associated with various disorders. We aimed to utilize laboratory variables and their corresponding ratios in serum and PE for the differential diagnosis of multiple types of PE based on a decision tree (DT) algorithm.

METHODS

A total of 1435 untreated patients with PE admitted to The First Affiliated Hospital of Ningbo University were enrolled. The demographic and laboratory variables were collected and compared. The receiver operating characteristic curve was used to select important variables for diagnosing malignant pleural effusion (MPE) or tuberculous pleural effusion (TPE) and included in the DT model. The data were divided into the training set and the test set at a ratio of 7:3. The training data was used to develop the DT model, and the test data was for evaluating the model. Independent data was collected as external validation.

RESULTS

Three PE indicators (carcinoembryonic antigen, adenosine deaminase [ADA], and total protein), two serum indicators (neuron-specific enolase and cytokeratin 19 fragments), and two ratios [high-sensitivity C-reactive protein (hsCRP)/ PE lymphocyte and hsCRP/PE ADA] were used to construct the DT model. The area under the curve (AUC), sensitivity, and specificity for diagnosing MPE were 0.963, 84.0%, 91.6% in the training set, 0.976, 84.1%, 88.6% in the test set, and 0.955,83.3%, 86.7% in the external validation set. The AUC, sensitivity, and specificity of diagnosing TPE were 0.898, 86.8%, 92.3% in the training set, 0.888, 88.8%, 92.7% in the test set, and 0.778, 84.8%, 94.3% in the external validation set.

CONCLUSION

The DT model showed good diagnostic efficacy and could be applied for the differential diagnosis of MPE and TPE in clinical settings.

MicroRNAs Present in Malignant Pleural Fluid Increase the Migration of Normal Mesothelial Cells In Vitro and May Help Discriminate between Benign and Malignant Effusions

The sensitivity of pleural fluid (PF) analyses for the diagnosis of malignant pleural effusions (MPEs) is low to moderate. Knowledge about the pathobiology and molecular characteristics of this condition is limited. In this study, the crosstalk between stromal cells and tumor cells was investigated in vitro in order to reveal factors that are present in PF which can mediate MPE formation and aid in discriminating between benign and malignant etiologies. Eighteen PF samples, in different proportions, were exposed in vitro to mesothelial MeT-5A cells to determine the biological effects on these cells. Treatment of normal mesothelial MeT-5A cells with malignant PF increased cell viability, proliferation, and migration, and activated different survival-related signaling pathways. We identified differentially expressed miRNAs in PF samples that could be responsible for these changes. Consistently, bioinformatics analysis revealed an enrichment of the discovered miRNAs in migration-related processes. Notably, the abundance of three miRNAs (miR-141-3p, miR-203a-3, and miR-200c-3p) correctly classified MPEs with false-negative cytological examination results, indicating the potential of these molecules for improving diagnosis. Malignant PF produces phenotypic and functional changes in normal mesothelial cells. These changes are partly mediated by certain miRNAs, which, in turn, could serve to differentiate malignant from benign effusions.

Acquiring tissue for advanced lung cancer diagnosis and comprehensive biomarker testing: A National Lung Cancer Roundtable best-practice guide

Advances in biomarker-driven therapies for patients with nonsmall cell lung cancer (NSCLC) both provide opportunities to improve the treatment (and thus outcomes) for patients and pose new challenges for equitable care delivery. Over the last decade, the continuing development of new biomarker-driven therapies and evolving indications for their use have intensified the importance of interdisciplinary communication and coordination for patients with or suspected to have lung cancer. Multidisciplinary teams are challenged with completing comprehensive and timely biomarker testing and navigating the constantly evolving evidence base for a complex and time-sensitive disease. This guide provides context for the current state of comprehensive biomarker testing for NSCLC, reviews how biomarker testing integrates within the diagnostic continuum for patients, and illustrates best practices and common pitfalls that influence the success and timeliness of biomarker testing using a series of case scenarios.

Impact of thoracic tumor radiotherapy on survival in non-small-cell lung cancer with malignant pleural effusion treated with targeted therapy: Propensity score matching study

BACKGROUND

EGFR-mutant (EGFR-M) and ALK-positive (ALK-P)are common in malignant pleural effusion (MPE) with metastatic non-small-cell lung cancer (NSCLC) (MPE-NSCLC). The impact of thoracic tumor radiotherapy on survival in such patients remains unclear. We aimed to investigate whether thoracic tumor radiotherapy could improve overall survival (OS) in such patients.

METHODS

According to whether or not patients accepted thoracic tumor radiotherapy, 148 patients with EGFR-M or ALK-P MPE-NSCLC treated with targeted therapy were classified into two groups: DT group without thoracic tumor radiotherapy and DRT group with thoracic tumor radiotherapy. Propensity score matching (PSM) was performed to balance clinical baseline characteristics. Overall survival was analyzed by Kaplan-Meier, compared by log-rank test, and evaluated using Cox proportional hazards model.

RESULTS

Median survival time (MST) was 25 months versus 17 months in the DRT group and DT group. The OS rates at 1, 2, 3, 5 years in the DRT group and DT group were 75.0%, 52.8%, 26.8%, 11.1% and 64.5%, 28.4%, 9.2%, 1.8%, respectively (χ2  = 12.028, p = 0.001). Compared with DT group, the DRT group still had better survival after PSM (p = 0.007). Before and after PSM, factors associated with better OS through multivariable analysis were that thoracic tumor radiotherapy, radiotherapy, N0-2 , and ALK-TKIs. Grades 4-5 radiation toxicities were not observed in patients; 8 (11.6%) and 7 (10.1%) out of the DRT group suffered from Grade 3 radiation esophagitis and radiation pneumonitis, respectively.

CONCLUSION

Our results for EGFR-M or ALK-P MPE-NSCLC showed that thoracic tumor radiotherapy may be crucial factor in improving OS with acceptable toxicities. Potential biases should not be neglected: Further randomized controlled trials are necessary to confirm this result.

Age affects the diagnostic accuracy of the cancer ratio for malignant pleural effusion

BACKGROUND AND OBJECTIVE

Cancer ratio (CR), which is defined as serum lactate dehydrogenase (LDH) to pleural fluid adenosine deaminase (ADA) ratio, has been reported to be a useful diagnostic marker for malignant pleural effusion (MPE). Whether its diagnostic accuracy is affected by age remains unknown. This study aimed to investigate the effects of age on the diagnostic accuracy of CR.

METHODS

The participants in this study were from a prospective cohort (SIMPLE cohort, n = 199) and a retrospective cohort (BUFF cohort, n = 158). All participants were patients with undiagnosed pleural effusion (PE). We used receiver operating characteristic (ROC) curves to evaluate the diagnostic accuracy of CR. The effect of age on the diagnostic accuracy of CR was investigated by adjusting the upper limit of age for participant enrolment.

RESULTS

Eighty-eight MPE patients were verified in the SIMPLE cohort, and thirty-five MPE patients were verified in the BUFF cohort. The AUCs of CR in the SIMPLE and BUFF cohorts were 0.60 (95% CI: 0.52-0.68) and 0.63 (95% CI: 0.54-0.71), respectively. In both cohorts, the AUCs of CR decreased with the advancement of age.

CONCLUSION

Age can affect the diagnostic accuracy of CR for MPE. CR has limited diagnostic value in older patients.

KEY MESSAGE

Cancer ratio is a promising diagnostic marker for malignant pleural effusion. This study revealed that its diagnostic accuracy decreased in older patients. Its diagnostic accuracy is overestimated by previous studies using tuberculosis and pneumonia patients as controls.

Expert Review on Contemporary Management of Common Benign Pleural Effusions

Heart failure (HF) and cirrhosis are frequently associated with pleural effusions (PEs). Despite their apparently benign nature, both HF-related effusions and hepatic hydrothorax (HH) have poor prognosis because they represent an advanced stage of the disease. Optimization of medical therapy in these two entities involve not only the use of diuretics, but also other pharmacological therapies. For instance, all HF patients with reduced or mildly reduced left ventricular ejection fraction can benefit from angiotensin receptor-neprilysin inhibitors, beta blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter 2 inhibitors. Conversely, it is better for HH patients to avoid nonselective beta blockers. Refractory cardiac- and cirrhosis-related PEs are commonly managed by iterative therapeutic thoracentesis. When repeated aspirations are needed, thereby diminishing quality of life, the insertion of an indwelling pleural catheter (IPC) may be warranted. However, in selected HH patients who are diuretic-resistant or diuretic-intractable, placement of transjugular intrahepatic portosystemic shunts should be considered as a bridge to liver transplantation, whereas in transplant candidates the role of IPC is debatable. Another benign condition, pleural tuberculosis (TB) is a serious health problem in developing countries. Diagnostic certainty is still a concern due to the paucibacillary nature of the infection, although the use of more sensitive nucleic acid amplification tests is becoming more widespread. Its treatment is the same as that of pulmonary TB, but the potential drug interactions between antiretroviral and anti-TB drugs in HIV-coinfected patients as well as the current recommended guidelines for the different types of anti-TB drugs resistance should be followed.

Deep learning for diagnosis of malign pleural effusion on computed tomography images

BACKGROUND

The pleura is a serous membrane that surrounds the lungs. The visceral surface secretes fluid into the serous cavity and the parietal surface ensures a regular absorption of this fluid. If this balance is disturbed, fluid accumulation occurs in the pleural space called "Pleural Effusion". Today, accurate diagnosis of pleural diseases is becoming more critical, as advances in treatment protocols have contributed positively to prognosis. Our aim is to perform computer-aided numerical analysis of Computed Tomography (CT) images from patients showing pleural effusion images on CT and to examine the prediction of malignant/benign distinction using deep learning by comparing with the cytology results.

METHODS

The authors classified 408 CT images from 64 patients whose etiology of pleural effusion was investigated using the deep learning method. 378 of the images were used for the training of the system; 15 malignant and 15 benign CT images, which were not included in the training group, were used as the test.

RESULTS

Among the 30 test images evaluated in the system; 14 of 15 malignant patients and 13 of 15 benign patients were estimated with correct diagnosis (PPD: 93.3%, NPD: 86.67%, Sensitivity: 87.5%, Specificity: 92.86%).

CONCLUSION

Advances in computer-aided diagnostic analysis of CT images and obtaining a pre-diagnosis of pleural fluid may reduce the need for interventional procedures by guiding physicians about which patients may have malignancies. Thus, it is cost and time-saving in patient management, allowing earlier diagnosis and treatment.

TRPS1 outperforms GATA3 in pleural effusions with metastatic breast carcinoma versus mesothelioma

INTRODUCTION

In evaluating malignant pleural fluid cytology, metastatic adenocarcinomas and mesotheliomas are often differential diagnoses. GATA binding protein 3 (GATA3) has historically been used to confirm metastatic breast carcinomas; however, GATA3 has low specificity if mesothelioma is included in differential diagnoses. Trichorhinophalangeal syndrome type 1 (TRPS1) protein is expressed in all types of breast carcinomas, with reported high specificity and sensitivity. We investigated the performance of TRPS1 immunohistochemistry (IHC) and compared it to GATA3 in pleural fluids diagnosed with metastatic breast carcinoma and mesothelioma.

METHODS

Thirty-six consecutive ThinPrep pleural fluids and 4 pleural fine needle aspirations (FNAs) with diagnoses of metastatic breast carcinoma (21) and mesothelioma (19) were retrieved, and IHC with TRPS1 and GATA3 was performed on all. Immunoreactivity scores for TRPS1 were calculated by multiplying percentage of immunoreactive cells by staining intensity. Immunoreactivity scores were negative if 0 or 1, low positive if 2, intermediate positive if 3 or 4, or high positive if 6 or 9. Nuclear immunoreactivity of ≥10% with at least moderate intensity was judged GATA3 positive.

RESULTS

GATA3 showed immunoreactivity in all metastatic breast carcinomas and 84% of mesotheliomas. TRPS1 was immunoreactive in all breast carcinoma cases (18 with a score of 9 and 3 with a score of 6). TRPS1 showed low positivity in 5% of mesothelioma cases with all other cases being negative.

CONCLUSION

When cytomorphologic differential diagnoses of mesothelioma exist, TRPS1 is a more specific marker than GATA3 for confirmation of metastatic breast carcinoma in pleural fluid cytology.

mRNA markers associated with malignant pleural effusion

Malignant pleural effusions (MPE) commonly result from malignant tumors and represent advanced-stage cancers. Thus, in clinical practice, early recognition of MPE is valuable. However, the current diagnosis of MPE is based on pleural fluid cytology or histologic analysis of pleural biopsies with a low diagnostic rate. This research aimed to assess the diagnostic ability of eight previously identified Non-Small Cell Lung Cancer (NSCLC)-associated genes for MPE. In the study, eighty-two individuals with pleural effusion were recruited. There were thirty-three patients with MPE and forty-nine patients with benign transudate. mRNA was isolated from the pleural effusion and amplified by Quantitative real-time PCR. The logistic models were further applied to evaluate the diagnostic performance of those genes. Four significant MPE-associated genes were discovered in our study, including Dual-specificity phosphatase 6 (DUSP6), MDM2 proto-oncogene (MDM2), Ring finger protein 4 (RNF4), and WEE1 G2 Checkpoint Kinase (WEE1). Pleural effusion with higher expression levels of MDM2 and WEE1 and lower expression levels of RNF4 and DUSP6 had a higher possibility of being MPE. The four-gene model had an excellent performance distinguishing MPE and benign pleural effusion, especially for pathologically negative effusions. Therefore, the gene combination is a suitable candidate for MPE screening in patients with pleural effusion. We also identified three survival-associated genes, WEE1, Neurofibromin 1 (NF1), and DNA polymerase delta interacting protein 2 (POLDIP2), which could predict the overall survival of patients with MPE.

Age affects the diagnostic accuracy of serum N-terminal pro-B-type natriuretic peptide for heart failure in patients with pleural effusion

BACKGROUND

Serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a well-recognized diagnostic marker for heart failure (HF) in patients with dyspnea or pleural effusion (PE). The effects of age on the diagnostic accuracy of NT-proBNP in dyspneic patients are widely known; however, whether its diagnostic accuracy is affected by age in patients with PE remains unknown. This study aimed to investigate the influence of age on the diagnostic accuracy of serum NT-proBNP for HF in patients with PE.

METHODS

Patients with PE were recruited from the BUFF (Biomarkers for patients with Undiagnosed pleural eFFusion) cohort and the SIMPLE (a Study Investigating Markers in PLeural Effusion) cohort. Serum NT-proBNP on admission and final diagnosis were extracted from the participant's medical records. The diagnostic accuracy of serum NT-proBNP was evaluated by a operating characteristic (ROC) curve analysis. The influence of age on the diagnostic accuracy of NT-proBNP was investigated through subgroup analyses.

RESULTS

One hundred and four participants were enrolled from the BUFF cohorts (HF, 32; non-HF, 72). One hundred and sixteen participants were enrolled from the SIMPLE cohort (HF, 21; non-HF, 95). The area under the ROC curve (AUCs) of NT-proBNP in the pooled cohort was 0.78 (95 %CI: 0.71 - 0.85). The AUC of NT-proBNP decreased in older patients.

CONCLUSION

Serum NT-proBNP has moderate diagnostic accuracy for HF in old patients with PE. The diagnostic accuracy of serum NT-proBNP in these patients decreases with the advancement of age.

Pleural CEA, CA-15-3, CYFRA 21-1, CA-19-9, CA-125 discriminating malignant from benign pleural effusions: Diagnostic cancer biomarkers

INTRODUCTION

There is a need for a rapid, accurate, less-invasive approach to distinguishing malignant from benign pleural effusions. We investigated the diagnostic value of five pleural tumor markers in exudative pleural effusions.

METHODS

By immunochemiluminescence assay, we measured pleural concentrations of tumor markers. We used the receiver operating characteristic curve analysis to assess their diagnostic values.

RESULTS

A total of 281 patients were enrolled. All tumor markers were significantly higher in malignant pleural effusions than benign ones. The area under the curve of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 15-3, cytokeratin fragment 19 (CYFRA) 21-1, CA-19-9, and CA-125 were 0.81, 0.78, 0.75, 0.65, and 0.65, respectively. Combined markers of CEA + CA-15-3 and CEA + CA-15-3 + CYFRA 21-1 had a sensitivity of 87% and 94%, and specificity of 75% and 58%, respectively. We designed a diagnostic algorithm by combining pleural cytology with pleural tumor marker assay. CEA + CYFRA 21-1 + CA-19-9 + CA-15-3 was the best tumor markers panel detecting 96% of cytologically negative malignant pleural effusions, with a negative predictive value of 98%.

CONCLUSIONS

Although cytology is specific enough, it has less sensitivity in identifying malignant pleural fluids. As a result, the main gap is detecting malignant pleural effusions with negative cytology. CEA was the best single marker, followed by CA-15-3 and CYFRA 21-1. Through both cytology and suggested panels of tumor markers, malignant and benign pleural effusions could be truly diagnosed with an accuracy of about 98% without the need for more invasive procedures, except for the cohort with negative cytology and a positive tumor markers panel, which require more investigations.

Diagnostic value of soluble biomarkers for parapneumonic pleural effusion

Parapneumonic pleural effusion (PPE) is a common complication in patients with pneumonia. Timely and accurate diagnosis of PPE is of great value for its management. Measurement of biomarkers in circulating and pleural fluid have the advantages of easy accessibility, short turn-around time, objectiveness and low cost and thus have utility for PPE diagnosis and stratification. To date, many biomarkers have been reported to be of value for the management of PPE. Here, we review the values of pleural fluid and circulating biomarkers for the diagnosis and stratification PPE. The biomarkers discussed are C-reactive protein, procalcitonin, presepsin, soluble triggering receptor expressed on myeloid cells 1, lipopolysaccharide-binding protein, inflammatory markers, serum amyloid A, soluble urokinase plasminogen activator receptor, matrix metalloproteinases, pentraxin-3 and cell-free DNA. We found that none of the available biomarkers has adequate performance for diagnosing and stratifying PPE. Therefore, further work is needed to identify and validate novel biomarkers, and their combinations, for the management of PPE.

Value of human epididymis secretory protein 4 in differentiating malignant from benign pleural effusion: an analysis of two cohorts

BACKGROUND

Lung cancer is the most common cause of malignant pleural effusion (MPE). Serum human epididymis secretory protein 4 (HE4) is a useful diagnostic marker for lung cancer.

OBJECTIVE

This study aimed to evaluate the diagnostic accuracy of pleural fluid HE4 for MPE.

DESIGN

A prospective, double-blind diagnostic test accuracy study.

METHODS

Patients with undiagnosed pleural effusion were enrolled in two cohorts (Hohhot and Changshu). Electrochemiluminescence immunoassay was used to detect pleural fluid HE4. The diagnostic accuracy of HE4 was evaluated by a receiver operating characteristic (ROC) curve, and the net benefit of HE4 was assessed by a decision curve analysis (DCA).

RESULTS

A total of 66 MPEs and 86 benign pleural effusions (BPEs) were enrolled in the Hohhot cohort. In the Changshu cohort, 26 MPEs and 32 BPEs were enrolled. In both cohorts, MPEs had significantly higher pleural fluid HE4 than BPEs. The area under the ROC curve (AUC) of HE4 was 0.73 (95% CI: 0.64-0.81) in the Hohhot cohort and 0.79 (95% CI: 0.67-0.91) in the Changshu cohort. At a threshold of 1300 pmol/L, HE4 had sensitivities of 0.44 (95% CI: 0.33-0.56) in the Hohhot cohort and 0.54 (95% CI: 0.35-0.73) in the Changshu cohort. The corresponding specificities were 0.90 (95% CI: 0.83-0.95) in the Hohhot cohort and 0.94 (95% CI: 0.84-1.00) in the Changshu cohort. In subgroup analyses, HE4 had an AUC (95% CI) of 0.78 (0.71-0.85) in exudates and an AUC of 0.69 (0.57-0.81) in patients with negative effusion cytology. The DCA revealed that HE4 determination had a net benefit in both cohorts.

CONCLUSION

Pleural fluid HE4 has moderate diagnostic accuracy for MPE and has net benefit in pleural effusion patients with unknown etiology.

Diagnostic sensitivity of pleural fluid cytology in malignant pleural effusions: systematic review and meta-analysis

BACKGROUND

Pleural fluid cytology is an important diagnostic test used for the investigation of pleural effusions. There is considerable variability in the reported sensitivity for the diagnosis of malignant pleural effusions (MPE) in the literature.

OBJECTIVE

The purpose of this review is to determine the diagnostic sensitivity of pleural fluid cytology for MPE, both overall and by tumour type, to better inform the decision-making process when investigating pleural effusions.

DATA SOURCES

A literature search of EMBASE and MEDLINE was performed by four reviewers. Articles satisfying inclusion criteria were evaluated for bias using the QUADAS-2 tool.

DATA EXTRACTION

For quantitative analysis, we performed a metaanalysis using a binary random-effects model to determine pooled sensitivity. Subgroup analysis was performed based on primary cancer site and meta-regression by year of publication.

SYNTHESIS

Thirty-six studies with 6057 patients with MPE were included in the meta-analysis. The overall diagnostic sensitivity of pleural fluid cytology for MPE was 58.2% (95% CI 52.5% to 63.9%; range 20.5%-86.0%). There was substantial heterogeneity present among studies (I² 95.5%). For primary thoracic malignancies, sensitivity was highest in lung adenocarcinoma (83.6%; 95% CI 77.7% to 89.6%) and lowest in lung squamous cell carcinoma (24.2%; 95% CI 17.0% to 31.5%) and mesothelioma (28.9%; 95% CI 16.2% to 41.5%). For malignancies with extrathoracic origin, sensitivity was high for ovarian cancer (85.2%; 95% CI 74.2% to 96.1%) and modest for breast cancer (65.3%; 95% CI 49.8% to 80.8%).

CONCLUSIONS

Pleural fluid cytology has an overall sensitivity of 58.2% for the diagnosis of MPE. Clinicians should be aware of the high variability in diagnostic sensitivity by primary tumour type as well as the potential reasons for false-negative cytology results.PROSPERO registration numberCRD42021231473.

Diagnosis and Treatment of Pleural Effusion. Recommendations of the Spanish Society of Pulmonology and Thoracic Surgery. Update 2022

Pleural effusion (PE) is a common yet complex disease that requires specialized, multidisciplinary management. Recent advances, novel diagnostic techniques, and innovative patient-centered therapeutic proposals have prompted an update of the current guidelines. This document provides recommendations and protocols based on a critical review of the literature on the epidemiology, etiology, diagnosis, prognosis, and new therapeutic options in PE, and addresses some cost-effectiveness issues related to the main types of PE.

A comparative study of diagnostic accuracy in 3026 pleural biopsies and matched pleural effusion cytology with clinical correlation

BACKGROUND

Pleural effusion can be caused by a wide range of benign and malignant conditions. Pleural biopsy and effusion cytology represent two key methods of pathological diagnosis. To compare the performance these two methods, a large cohort of matched pleural biopsy and effusion cytology with clinical follow-up was reviewed.

METHODS

Pleural biopsies and effusion cytology specimens over a period of 18 years were retrieved. Cytology specimens collected within 7 days of pleural biopsy were matched. Reports were reviewed, and the cause for pleural effusion was determined by hospital disease coding and clinical data.

RESULTS

Totally, 3026 cases were included. The leading cause of benign effusion was tuberculosis (n = 650). Malignant pleural effusion (MPE) was more common in older females (p < 0.001) and mostly due to lung cancer (n = 959), breast cancer (n = 64), and mesothelioma (n = 48). The inadequate/insufficient (B1/C1) rate of biopsy was higher than cytology (15.6% vs. 0.3%) but the rates for other diagnostic categories were similar. Biopsy and cytology showed a correlation coefficient of 0.315, improving to 0.449 when inadequate/insufficient (B1/C1) cases were excluded. The ROM for benign cytology (C2) was lower than biopsy (B2) (p < 0.001). Compared with biopsy, the diagnostic accuracy was higher in cytology overall and for metastatic carcinomas (p < 0.001) but lower for hematolymphoid malignancies (p = 0.014) and mesotheliomas (p = 0.002).

CONCLUSIONS

These results suggest that effusion cytology may be better for confirming benignity and diagnosing carcinomatous MPE. In these cases, pleural biopsy may be withheld to reduce procedural risks. However, for suspected hematolymphoid malignancies and mesothelioma, biopsy should be considered.

Evaluation of Exudative Pleural Effusions: A Multicenter, Prospective, Observational Study

PURPOSE

The aim of this study is to determine the diagnostic performances of pleural procedures in undiagnosed exudative pleural effusions and to evaluate factors suggestive of benign or malignant pleural effusions in tertiary care centers.

METHODS

This was a multicenter prospective observational study conducted between January 1 and December 31, 2018. A total of 777 patients with undiagnosed exudative pleural effusion after the initial work-up were evaluated. The results of diagnostic procedures and the patients' diagnoses were prospectively recorded. Sensitivity, specificity, and accuracy estimates with 95% confidence intervals were used to examine the performance of pleural procedures to detect malignancy.

RESULTS

The mean age ± SD of the 777 patients was 62.0 ± 16.0 years, and 68.3% of them were male. The most common cause was malignancy (38.3%). Lung cancer was the leading cause of malignant pleural effusions (20.2%). The diagnostic sensitivity and accuracy of cytology were 59.5% and 84.3%, respectively. The diagnostic sensitivity of image-guided pleural biopsy was 86.4%. The addition of image-guided pleural biopsy to cytology increased diagnostic sensitivity to more than 90%. Thoracoscopic biopsy provided the highest diagnostic sensitivity (94.3%). The highest diagnostic sensitivity of cytology was determined in metastatic pleural effusion from breast cancer (86.7%).

CONCLUSION

The diagnostic performance increases considerably when cytology is combined with image-guided pleural biopsy in malignant pleural effusions. However, to avoid unnecessary interventions and complications, the development of criteria to distinguish patients with benign pleural effusions is as important as the identification of patients with malignant pleural effusions.

Diagnostic accuracy of pleural fluid lactate dehydrogenase to adenosine deaminase ratio for tuberculous pleural effusion: an analysis of two cohorts

Background

This study aimed to evaluate the diagnostic accuracy of pleural fluid (PF) lactate dehydrogenase (LDH) to adenosine deaminase (ADA) (LDH/ADA) ratio for tuberculous pleural effusion (TPE). Especially to explore whether the LDH/ADA ratio provides added diagnostic value to ADA.

Methods

The diagnostic accuracy of PF LDH/ADA ratio and ADA for TPE was evaluated in two cohorts, named the BUFF (Biomarkers for patients with Undiagnosed pleural eFFusion) cohort (62 with TPE and 194 with non-TPE) and the SIMPLE (a Study Investigating Markers in PLeural Effusion) cohort (33 with TPE and 177 with non-TPE). Receiver operating characteristic (ROC) curve and decision curve were used to measure the diagnostic accuracy of the PF LDH/ADA ratio. The added diagnostic value of the LDH/ADA ratio to ADA was evaluated with net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

Results

The area under the ROC curves (AUCs) of PF ADA and LDH/ADA ratio in the BUFF cohort were 0.76 and 0.74, respectively. In the SIMPLE cohort, the AUCs of PF ADA and LDH/ADA ratio were 0.80 and 0.85, respectively. The decision curves of PF LDH/ADA and ADA were close in both the BUFF and SIMPLE cohorts. The NRI and IDI analyses did not reveal any added diagnostic value of LDH/ADA to ADA.

Conclusions

PF LDH/ADA ratio has moderate diagnostic accuracy for TPE. It does not provide added diagnostic value beyond ADA. The current evidence does not support LDH/ADA ratio for diagnosing TPE.

Recommendations of the Spanish Society of Thoracic Surgery for the management of malignant pleural effusion

This article summarizes the clinical guidelines for the diagnosis and treatment of malignant pleural effusion (MPE) sponsored by the Spanish Society of Thoracic Surgery (SECT). Ten clinical controversies were elaborated under the methodology of PICO (Patient, Intervention, Comparison, Outcome) questions and the quality of the evidence and grading of the strength of the recommendations was based on the GRADE system. Immunocytochemical and molecular analyses of pleural fluid may avoid further invasive diagnostic procedures. Currently, the definitive control of MPE can be achieved either by pleurodesis (talc poudrage or slurry) or the insertion of a indwelling pleural catheter (IPC). It is likely that the combination of both techniques (i.e., thoracoscopy with talc poudrage and insertion of a IPC, or instillation of talc slurry through a IPC) will have a predominant role in the future therapeutic management.

Factores de riesgo y mortalidad de los derrames pleurales que precisan de una toracocentesis diagnóstica

Introduction

Occurrence of malignant pleural effusion (PE) is known to be associated with a poor prognosis, but the mortality of patients with non-malignant effusions has not been sufficiently studied. Our objective was to describe the clinical course and explore risk factors associated with all-cause mortality at 1, 5 and 10 years in patients who develop a PE.

Methods

Retrospective observational study of patients undergoing diagnostic thoracentesis during the decade 2008-2017 in a pulmonology service. Demographic, biochemical, pathological and evolutionary variables were evaluated. The etiology of the effusions was determined using standardized criteria.

Results

Pleural fluid samples from 358 patients with a mean age of 68.9 years (SD 15.1 years), 69.2% males, were analyzed. Malignant (29.4%), parapneumonic (19.8%) and secondary to heart failure (18.9%) effusions predominated. Patients with malignant and heart failure related PE had 1-year mortality rates of 60.0% and 30.8%, respectively, and 85% and 64.7% at 5 years. Male gender (hazard ratio [HR] 1.46; 95% CI: 1.03-2.07), positive cytology for malignancy (HR 1.66; 95% CI: 1.03-2.68) and effusion recurrence (HR 1.61; 95% CI: 1.17-2.21) were associated with a worse prognosis and 5-year mortality.

Conclusions

Patients undergoing thoracentesis for effusion have a high short and long-term mortality. In our series of hospitalized patients with PE, the factors associated with higher mortality at 1 and 5 years were age, male sex, recurrence of PE, and coexistence of malignancy.

Nonmalignant Pleural Effusions

Although the potential causes of nonmalignant pleural effusions are many, the management of a few, including complicated pleural infections and refractory heart failure and hepatic hydrothoraces, can be challenging and requires the assistance of interventional pulmonologists. A pragmatic approach to complicated parapneumonic effusions or empyemas is the insertion of a small-bore chest tube (e.g., 14-16 Fr) through which fibrinolytics (e.g., urokinase and alteplase) and DNase are administered in combination. Therapeutic thoracenteses are usually reserved for small to moderate effusions that are expected to be completely aspirated at a single time, whereas video-assisted thoracic surgery should be considered after failure of intrapleural enzyme therapy. Refractory cardiac and liver-induced pleural effusions portend a poor prognosis. In cases of heart failure-related effusions, therapeutic thoracentesis is the first-line palliative therapy. However, if it is frequently needed, an indwelling pleural catheter (IPC) is recommended. In patients with hepatic hydrothorax, repeated therapeutic thoracenteses are commonly performed while a multidisciplinary decision on the most appropriate definitive management is taken. The percutaneous creation of a portosystemic shunt may be used as a bridge to liver transplantation or as a potential definitive therapy in nontransplant candidates. In general, an IPC should be avoided because of the high risk of complications, particularly infections, that may jeopardize candidacy for liver transplantation. Even so, in noncandidates for liver transplant or surgical correction of diaphragmatic defects, IPC is a therapeutic option as valid as serial thoracenteses.

Pleural homocysteine for malignant pleural effusion: A prospective and double-blind diagnostic test accuracy study

OBJECTIVE

To assess the accuracy of pleural fluid homocysteine for discriminating malignant pleural effusion (MPE) and benign pleural effusion (BPE).

METHODS

A total of 194 patients from two cohorts (Hohhot and Changshu) with undiagnosed pleural effusion were prospectively enrolled. Their pleural homocysteine was measured, and its diagnostic accuracy and net benefit for MPE were analyzed by receiver operating characteristic (ROC) curve analysis and decision curve analysis, respectively.

RESULTS

In the Hohhot cohort (n = 136) and the Changshu cohort (n = 58), MPE patients had significantly higher homocysteine levels than BPE patients. The areas under the ROC curves of homocysteine for the diagnosis of MPE were 0.61 (p = 0.027) and 0.59 (p = 0.247), respectively. The decision curves of homocysteine were close to the reference line in both the Hohhot cohort and the Changshu cohort.

CONCLUSION

The diagnostic accuracy of pleural fluid homocysteine for MPE was low.

Comparison of clinical manifestation among Australian Indigenous and non-indigenous patients presenting with pleural effusion

BACKGROUND

There is sparse evidence in the literature in relation to the nature and causes of pleural effusion among Australian Indigenous population.

AIM

To investigate the clinical and demographic characteristics of adult indigenous patients presenting with pleural effusion in the Northern Territory of Australia.

METHODS

In this retrospective study, indigenous and non-indigenous adults diagnosed to have pleural effusion over a 2-year study period were included for comparative analysis.

RESULTS

Of the 314 patients, 205 (65%) were non-indigenous and 52% were male. In comparison with non-indigenous patients, the indigenous patients were younger (50 years (interquartile range (IQR) 39-60) vs 63 years (IQR 52-72); P < 0.001), female (61% vs 41%; P = 0.001), had a higher prevalence of renal and cardiovascular disease and tended to have exudative effusion (93% vs 76%; P = 0.032). Infections were judged to be the most common cause of effusion in both groups, more so among the indigenous cohort. Effusion secondary to renal disease was higher (13% vs 1%; P < 0.001) among Australian Indigenous patients, but in contrast, malignant effusions were higher (13% vs 4%; P = 0.004) among non-indigenous patients. Length of hospital stay was longer for indigenous patients (P = 0.001), and a greater proportion received renal dialysis (13% vs 1%; P < 0.001). Intensive care unit admission rates were higher with infective aetiology of pleural effusion (82% vs 53% indigenous and 44% vs 39% non-indigenous respectively). Re-presentations to hospital were higher among indigenous patients (46% vs 33%; P = 0.046) and were associated with renal and cardiac disease and malignancy in non-indigenous patients.

CONCLUSION

There are significant differences in the way pleural effusion manifests among Australian Indigenous patients. Understanding these differences might facilitate approaches to management and to implementation of strategies to reduce morbidity and mortality in this population.

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.

Management of Malignant Pleural Effusion: Where Are We Now?

Pleural malignancies are among the most common causes of pleural disease and form the basis of our daily pleural practice. There has been significant research and increase in both diagnostic and therapeutic management of malignant pleural diseases in the last decade. Good-quality data have led to a paradigm shift in the management options of pleural malignancies, and indwelling pleural catheter is now recommended and widely used as first-line intervention. Several trials compared different treatment modalities for pleural malignancies and continue to emphasize the need to reduce hospital length of stay and unnecessary pleural intervention, and the importance of patient choice in clinical decision making. This practical review aims to summarize the current knowledge for the management of pleural malignancies, and the understanding of the steps that we still have to climb to optimize management and reduce morbidity.

Diagnostic Value of Six Tumor Markers for Malignant Pleural Effusion in 1,230 Patients: A Single-Center Retrospective Study

Background: The diagnostic value of tumor markers in pleural effusion (PE) and serum for malignant pleural effusion (MPE) is still in debate. This study aimed to evaluate the diagnostic value of six tumor markers in PE, serum, and the corresponding PE/serum (PE/S) ratio in distinguishing MPE from benign pleural effusion (BPE).

Methods: A total of 1,230 patients with PE (452 MPEs and 778 BPEs) were retrospectively included in the study. PE and serum levels of carcinoembryonic antigen (CEA), carbohydrate antigen 15-3 (CA15-3), carbohydrate antigen 125 (CA125), carbohydrate antigen 19-9 (CA19-9), cytokeratin 19 fragment (CYFRA 21-1), and neuron-specific enolase (NSE) were measured. The area under the curve (AUC) was used to assess the single and combined diagnostic values of the six tumor markers for MPE.

Results: The levels of the six tumor markers in PE, serum, and PE/S were significantly higher in MPE than that in BPE, except for serum CA125. PE CEA showed the highest AUC [0.890 (0.871–0.907)] at a cut-off value of 3.7 ng/ml compared to any single tumor marker using receiver operating characteristic (ROC) analysis. The specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of PE CEA were 74.1%, 95.5%, 90.5%, 86.4%, 16.47, and 0.27, respectively. The combination of PE CEA and serum CYFRA21-1 showed the best diagnostic performance with an AUC of 0.934 (sensitivity, 79.9%; specificity, 95.7%, PPV, 90.5; PLR, 17.35) among all two or three combinations. Besides, serum CYFRA21-1 was the best diagnostic tumor marker in distinguishing cytology-negative MPE from BPE at a cut-off value of 3.0 ng/ml.

Conclusion: PE CEA was the best diagnostic tumor marker in distinguishing MPE from BPE. Serum CYFRA21-1 was the best diagnostic tumor marker in distinguishing cytology-negative MPE from BPE. The combination of PE CEA and serum CYFRA21-1 could increase the diagnostic performance in distinguishing MPE from BPE and cytology-negative MPE from BPE.

Pleural Effusions and Pericarditis: A Retrospective Cohort Study of Patients Undergoing Cardiac Magnetic Resonance Imaging

Background

Pleural effusions can occur due to acute pericarditis and can necessitate intervention. We sought to add to the evidence base by performing a retrospective review of patients presenting to the advanced cardiac imaging unit with pericarditis and pleural effusion to determine laterality, trends in pleural fluid analyses, and the need for pleural intervention. Local ethical (Caldicott) approval was obtained for this study.

Methodology

Descriptive statistical methodology was applied with continuous data presented as mean (standard deviation, SD; range) and categorical variables as frequencies or percentages.

Results

In 60 patients with pericarditis, 24 (39%) had pleural effusions on contemporaneous imaging. The mean age of the study population was 63.3 years (range: 20-83), and 17 patients were males. Diagnoses were viral (five), rheumatological (one), amyloidosis (one), listeria (one), and the rest idiopathic (17). Four effusions were only left-sided, one right-sided, and 20 bilateral. Ten pleural taps were performed, one for a unilateral effusion and nine for one side being bigger than the other. The mean pH was 7.46 (7.33-7.6), mean lactate dehydrogenase was 210 (74-393 U/L), mean fluid protein was 36.1 (19-56 g/L) (four effusions exudative/three transudative), mean glucose was 5.8 (4.8-6.8 mmol/L), and all cytologies were negative. Five patients underwent large volume aspirations for symptom control. Three indwelling pleural catheters (IPC) were placed for treatment refractory effusions. There was one pleural space infection in six months related to an IPC. There were three deaths at 12 months, with none related to pericarditis.

Conclusions

Pleural effusions associated with pericarditis are usually small, bilateral, and exudative. Treatment refractory cases require pleural intervention, with aspirations, drains, and IPCs being viable options. Further prospective studies are warranted.