Malignant pleural effusion: from bench to bedside

Pleural effusion as a sample matrix for laboratory analyses in cancer management: a perspective

Malignant effusions, pleural effusion or ascites, represent a common problem in cancer patients. Pleural effusion in a cancer patient may be caused also by non-neoplastic conditions, and the diagnosis of malignant pleural effusion is established by the demonstration of tumor cells in pleural fluid. Microscopical detection of tumor cells in pleural fluid often fails, and there is an unmet medical need for more sensitive methods. New approaches, including isolation using magnetic beads coated with monoclonal antibodies targeting antigens expressed on tumor cells not only increase the diagnostic sensitivity, but also provide material for the analysis of predictive biomarkers. The advent of new technologies illustrates the incremental role of laboratory medicine in the management of patients with malignant effusions.

Intrapleural Fibrinolytic Therapy for Loculated Malignant Pleural Effusion: A Systematic Review and Meta-analysis

BACKGROUND

Malignant pleural effusion (MPE) is a common complication in advanced malignancies, often presenting with dyspnea and impaired quality of life. Management can be challenging, particularly in cases with loculated effusions or non-expandable lungs. Intrapleural fibrinolytic therapy (IFT) has been proposed as a potential adjunctive treatment, although its efficacy for loculated MPE remains inconclusive METHODS: A systematic search was conducted across PubMed and Embase, and a meta-analysis was conducted to assess the efficacy and safety of IFT for MPE. Eligible studies included randomized controlled trials (RCTs) and retrospective studies comparing IFT with control interventions. The primary outcome was respiratory improvement; secondary outcomes included complication rates, treatment failure or clinical recurrence, hemorrhagic complications, and hospital length of stay.

RESULTS

Six studies (n = 653) were included, comprising three RCTs and three retrospective cohort studies. IFT was associated with significantly greater respiratory improvement (OR = 5.25, 95% CI: 3.54-7.80, p < 0.05), with consistent findings in both RCT and retrospective subgroups. There were no statistically significant differences in overall complication rates, treatment failure, hemorrhagic complications, or length of hospital stay. Subgroup analyses revealed a higher complication OR in retrospective studies (OR = 3.36) and a lower OR in RCTs (OR = 0.78), although both were statistically non-significant.

CONCLUSION

IFT is associated with favorable respiratory outcomes in patients with MPE with an acceptable safety profile, suggesting its potential role as an adjunct to standard therapies.

Malignant Cell Count in Pleural Effusion: A Potential Indicator of Mortality

BACKGROUND

The role of malignant cell count in pleural fluid as a potential predictor of survival remains under investigation. This study aims to assess the relationship between malignant cell count in pleural effusion and mortality in patients with malignant pleural effusion (MPE).

METHODS

This retrospective cohort study was conducted at a tertiary referral and research hospital, including treatment-naive patients diagnosed with MPE. Univariate and multivariate Cox regression analyses were employed to identify independent predictors of mortality.

RESULTS

A total of 63 patients were included in the analysis, with a male predominance (39 males, 61.9%) and a mean age of 65.7 ± 12.5 years. The majority (76.2%) of patients had NSCLC. Patients were stratified based on malignant cell count into two groups: those with <1700 cells/2mm² and those with ≥1700 cells/2mm². The two groups were similar in demographics, blood and pleural fluid parameters, and comorbidities. Multivariate Cox regression analysis revealed that male gender (HR: 4.14, 95% CI: 1.65-10.39), active smoking (HR: 2.99, 95% CI: 1.25-7.16), and malignant cell count (HR: 0.23, 95% CI: 0.09-0.56) were independent predictors of mortality.

CONCLUSION

Our findings indicate that a malignant cell count of <1700 cells/2mm², male gender and active smoking are independent prognostic factors associated with increased mortality in patients with MPE. Further large-scale prospective studies are necessary to confirm the clinical relevance of cytological malignant cell counts and to explore the viability and functional significance of these cells.

Novel bioengineered drugs with immunotherapies for malignant pleural effusion: Remodulate tumor immune microenvironment and activate immune system

Malignant pleural effusion (MPE) remains a clinical issue since it is associated with advanced-stage cancers and dismal survival, with immunosuppressive tumor microenvironment (TME) and ineffective drug delivery. Conventional therapies such as thoracentesis and pleurodesis are for symptom relief but palliative, without inducing immunity and prolonging survival. Emerging new bioengineered drugs, synergizing with immunotherapies, offer a new paradigm by dual-targeting TME remodeling and immune activation. These technologies leverage nanotechnology, gene editing, and biomaterials to offer precise spatiotemporal control. This review illustrates the molecular mechanism of the immunosuppressive TME in MPE. It examines the newest bioengineering platforms-such as cytokine-encapsulated nanoparticles and oncolytic viruses-that can reactivate immune mechanisms. We highlight preclinical and clinical evidence of the effectiveness of combinatorial strategies in overcoming local immune tolerance and potential risks in adverse events. While the clinical transformation challenge remains, future directions necessitate cross-disciplinary convergence to engineer intelligent delivery vehicles and predictive biomarkers for patient stratification. By integrating immunotherapy with bioengineering, this strategy not only restores antitumor immunity but also portends a new epoch of precision medicine for MPE.

Pleural Space Diseases and Their Management: What is the Role of Intrapleural Fibrinolytic Therapy?

Pleural space diseases are a significant cause of morbidity in the United States with a reported 25% mortality rate within a year of diagnosis. Pleural space diseases, including intrapleural infections, retained hemothorax (RH), and malignant pleural effusions (MPE), often indicate advanced disease. Despite options like video-assisted thoracoscopy (VATS), tube thoracostomy, and intrapleural fibrinolytic therapy (IPFT), treatment remains a significant clinical challenge. IPFT, which describes a combination of administrating tissue plasminogen activator (tPA) and DNase through a chest tube, has shown effectiveness in improving fluid drainage and reducing surgery frequency in a large, randomized control trial and is widely used. However, the success of IPFT varies based on infection severity, patient health, and treatment timing, with a failure rate around 20-25%. This highlights the need for further research to enhance the therapy's efficacy, investigating both disease mechanisms and optimizing treatment protocols. This review seeks to provide a comprehensive overview of IPFT, highlighting recent advancements, current trends, and existing research gaps.

Predictors of Survival in Metastatic Malignant Pleural Effusions: The GASENT Score

OBJECTIVE

The therapeutic approach for metastatic malignant pleural effusion depends on the patient's life expectancy. Can survival be accurately estimated in these patients using a risk-prediction model?

METHODS

A prospective, single-center study was conducted to examine the prognostic value of pre-established variables (multivariate Cox model). Subsequently, a prognostic score was developed and validated. The inclusion period was 11 years long. Follow-up was conducted until death or for a minimum of 12 months.

RESULTS

The derivation and validation cohorts included 475 and 205 patients, respectively. The prognostic score GASENT (Galicia, Age, Sex, ECOG-PS, Neutrophil/lymphocyte ratio, and Tumor type) was derived from the multivariate analysis of survival. Categorization of patients in the derivation cohort into low-, moderate-, or high-risk yielded median survival times of 477 days (377-665; n=159), 108 days (83-156; n=158), and 35 days (27-47; n=158), respectively. Survival rates at 1, 3, and 6 months were 92%, 83%, and 72%, respectively, for the low-risk group; 80%, 55%, and 36%, respectively, for the moderate-risk group; and 55%, 23%, and 13%, respectively, for the high-risk group. The analysis of areas under the curve revealed that the GASENT model was superior to the LENT score as a survival predictive model at 1 (0.777 vs. 0.737; p=0.009), 3 (0.810 vs. 0.778; p=0.009), and 6 months (0.812 vs. 0.780; p=0.007).

CONCLUSIONS

The GASENT predictive model estimates survival in patients with metastatic malignant effusions with significantly greater accuracy than the scores categorizing patients by risk groups.

Development and validation of a machine learning-based nomogram for predicting prognosis in lung cancer patients with malignant pleural effusion

Malignant pleural effusion (MPE) is a common complication in patients with advanced lung cancer, significantly impacting their survival rates and quality of life. Effective tools for assessing the prognosis of these patients are urgently needed to enable early intervention. This study retrospectively analyzed patient data from the Affiliated Hospital of North Sichuan Medical College from 2013 to 2021, which served as the training cohort and internal testing cohort. Additionally, three external testing cohorts were introduced: data from Guang'an People's Hospital as cohort 1, data from Dazhou Central Hospital as cohort 2, and data from the Affiliated Hospital of North Sichuan Medical College from January 1, 2023, to December 31, 2023, constituting the temporal external testing cohort. Univariate logistic regression (LR) analysis of clinical variables (P < 0.05) was performed, followed by multivariate LR to identify independent predictors for inclusion in nine machine learning models: Decision Tree (DT), Random Forest (RF), Extreme Gradient Boosting (XGBoost), Elastic Net (Enet), Radial Support Vector Machine (rSVM), Multilayer Perceptron (MLP), LR, Light Gradient Boosting Machine (LightGBM), and K-Nearest Neighbors (KNN). The best-performing model was used to develop a nomogram for patient risk stratification. Three variables-treatment regimen, presence of pericardial effusion, and total pleural effusion volume-were identified as significant predictors in the study. The LR model demonstrated the best performance, achieving area under the curve (AUC) values of 0.885 in the training cohort, 0.954 in the internal testing cohort, and 0.920 in external testing cohort 1. To further validate the model's robustness, the nomogram developed from the LR model was evaluated in two additional validation cohorts: external testing cohort 2 and a temporal external testing cohort. The nomogram achieved AUCs of 0.962 in external testing cohort 2 and 0.949 in the temporal external testing cohort, demonstrating strong predictive accuracy. Calibration curves confirmed excellent model-reality concordance across all cohorts, and decision curve analysis (DCA) revealed superior clinical utility. The nomogram enabled individualized risk quantification and showed significant survival differences between high-risk/very high-risk groups and low-risk/medium-risk groups. This study evaluated nine machine learning models for prognostic prediction in lung cancer patients with MPE, finding that the LR-based model offered the best performance. A nomogram based on this model can effectively stratify patients for prognostic assessment and early intervention.

Exploring prognostic precision: a nomogram approach for malignant pleural effusion in lung cancer

BACKGROUND

Patients with lung cancer and malignant pleural effusion (MPE) often have poor prognoses. Accurate prognostic tools are needed to guide interventions and improve outcomes.

METHODS

We retrospectively analyzed clinical and imaging data from MPE patients at two medical centers. A nomogram was developed and externally validated. Clinical and imaging features were refined using least absolute shrinkage and selection operator (LASSO), and independent predictors were identified via multivariate logistic regression. Predictors were integrated into the nomogram, whose predictive performance, calibration, and clinical utility were evaluated using statistical analyses, including receiver operating characteristic (ROC) curves, calibration curves, Hosmer-Lemeshow tests, and decision curve analysis (DCA). Survival curves illustrated prognostic differences among risk groups.

RESULTS

The final nomogram included five variables: Lactate Dehydrogenase (LDH) levels in pleural fluid, clarity of pleural effusion, treatment regimen, presence of pericardial effusion, and total volume of pleural effusion. In both cohorts, the nomogram demonstrated strong predictive accuracy (Area Under the Curve (AUC): 0.929 and 0.941, respectively) and excellent calibration (Hosmer-Lemeshow test p-values: 0.944 and 0.425, respectively). DCA confirmed the nomogram's clinical utility. Risk stratification revealed significant survival disparities among patients.

CONCLUSION

Our nomogram accurately predicts the prognosis of lung cancer patients with MPE at initial diagnosis, incorporating key variables such as LDH levels in pleural fluid, clarity of pleural effusion, treatment regimen, pericardial effusion, and total volume of pleural effusion. Its robust predictive performance, calibration, and clinical utility support its use in guiding clinical decision-making for this patient population.

β-receptor blocker enhances anti-tumor immunity via inhibiting lactate-induced norepinephrine metabolism of macrophages during malignant pleural effusion

INTRODUCTION

Malignant pleural effusion (MPE) is associated with poor quality of life and mortality in patients with tumors. In clinical practice, we observed that patients with malignant pleural effusion (MPE) and concurrent heart disease exhibited a decrease in MPE volumes following treatment with β-receptor blockers for heart disease. Immunosuppressive tumor microenvironment was found to play a substantial role in the progression of MPE, and mainly attributed to tumor-associated macrophages (TAMs). However, whether β-receptor blockers improve MPE through affecting the immune microenvironment especially TAMs and the potential mechanism behind remains unclear.

METHODS

In this study, we collected the MPE samples from MPE and heart disease patients treated with propranolol, and performed flow cytometry experiment to evaluate the effect of propranolol on MPE immune microenvironment. Then, the mechanism that how propranolol effectively reprogrammed the immunosuppressive microenvironment of MPE was conducted by the experiments of mass spectrometry, RNA-seq, flow cytometry, immunofluorescence, western blotting, etc. Lastly, to further evaluate the effect of propranolol on MPE therapy in vivo, we developed a mouse model of MPE. We administrated propranolol into MPE-bearing mice to investigate the therapy efficacy and the changes of MPE microenvironment by the experiments of computed tomography (CT) scanning, flow cytometry, etc.

RESULTS

We observed that propranolol treatment in MPE patients with heart disease decreased TAM frequency and immunosuppression and enhanced anti-tumor immunity. Macrophages in MPE exhibited an immunosuppressive phenotype via the activation of norepinephrine metabolism. Subsequently, we found that lactate was increased in MPE and may contribute to an increase in TAM frequency and inhibition of anti-tumor immunity by macrophages. Additionally, lactate triggered phenylalanine/norepinephrine signaling and further induced macrophage immunosuppression in an ERK-depended way. Lastly, in the MPE mouse model, propranolol inhibited MPE development and reversed the immune microenvironment of MPE.

DISCUSSION

Here, we reveal the mechanism by which lactate induces macrophage immunosuppression via activating phenylalanine/norepinephrine signaling. Our findings highlight that blocking norepinephrine signaling by β-receptor blockers is an attractive therapeutic strategy to enhance anti-tumor immunity in the context of MPE.

A potential target for the future treatment of malignant pleural effusion: Monocyte chemoattractant protein-1 (MCP-1)

Background and Aim: Malignant pleural effusion (MPE) is a common clinical problem. Management options are mainly pleurodesis and drainage, and have remained unchanged for years. Novel therapies that target the molecules responsible for fluid formation are needed to reduce the need for invasive procedures. The aim of this study is to investigate the potential role of MCP-1 in the development of MPE in patients with metastatic pleural malignancies. Methods: Pleural effusion samples (8-10 ml) were collected from 100 patients who were divided into three groups: Group 1 (MPE, n = 56), Group 2 (benign exudate, n = 27) and Group 3 (transudate, n = 17). The collected effusions were promptly centrifuged at 4°C, and the supernatants were stored at -80°C. MCP-1 levels were determined by ELISA kit (USCN, Wuhan). Results: Median MCP-1 levels were found to be significantly different between the three groups (Group 1: 1303 pg/ml, Group 2: 926 pg/ml, Group 3: 211 pg/ml) (p < 0.001). MCP-1 levels were markedly higher but similar in Group 1 and Group 2, as compared to Group 3. When patients from Group 1 and Group 2 were combined, a positive correlation was observed between pleural fluid MCP-1 and LDH levels (r = 0.38; p = 0.001). Additionally, MCP-1 levels were observed to increase significantly as the volume of pleural fluid increased (p = 0.007). Conclusion: MCP-1 levels were found to be similarly high in both Group 1 (MPE) and Group 2 (Benign exudate), indicating that inflammation accompanying the tumor could play a role in the formation of pleural effusion. This suggests that the development of biological therapies targeting MCP-1 could be a promising approach in the future management of MPE.

Effects of patient pleural effusion fluids on the BBSome components expression of human benign mesothelial cells

Malignant pleural mesothelial cells are affected by the extracellular milieu although such data on benign cells are scarce. Benign cells sense the extracellular environment with the primary cilium (PC) and its molecular complex, the Bardet-Biedl syndrome family of proteins (BBSome), is critical for this process. Here we aimed to assess the changes in BBSome gene expression in ordinary two-dimensional (2-D) and spheroid three-dimensional (3-D) cell cultures after incubation with pleural effusion fluids (PFs) of several etiologies. The benign human mesothelial cells (MeT-5A) were incubated with PF from patients with mesothelioma (Meso-PF), breast cancer (BrCa-PF), hemothorax (Hemo-PF), and congestive heart failure (CHF-PF). Gene expression of BBS1, 2, 4, 5, 7, 9, and 18 was assessed by quantitative real-time PCR (qRT-PCR) to monitor PF-induced gene expression changes. MeT-5A cell migration using the PC-modulating drugs ammonium sulfate (AS) and lithium chloride (LC) during PF incubation was also determined. BBSome gene expression upon influence of BrCa-PF and Hemo-PF was more pronounced in 2-D compared with 3-D, inducing global changes in 2-D. CHF-PF and Meso-PF also induced changes in 2-D but not as many, while in all cases, MeT-5A grown in 3-D were more resistant to the effects of the PF. Meso-PF decreased 2-D cell migration, while the disturbance of PC in all PF cases resulted in decreased cell migration. These data suggest distinct BBSome molecular profile changes in benign mesothelial cells exposed to malignant and benign PF that is different in each case, in both 2-D and 3-D. Cell migration is sensitive to drug disturbance with PC modulators in PF-exposed cells.NEW & NOTEWORTHY Studying mesothelial PC in pleural physiology and pathophysiology is at an early stage. Previously, we have highlighted the role of the PC in mesothelial cell phenotypes as well as the role of BBSome components in the context of benign and malignant mesothelial cell physiology. Here we extended our contributions by providing evidence on the BBSome changes induced in benign mesothelial cells by their exposure to different etiology PFs.

What You Need to Know About: The Management of Malignant Pleural Effusion

Malignant pleural effusion (MPE) is a common complication of malignancy and is regularly seen on the general medicine take. Diagnosis of MPE is indicative of advanced or metastatic disease and carries a poor prognosis, with median survival ranging from 3 to 12 months. Despite recent advancements in systemic anti-cancer treatment, the goal of management in MPE remains the palliation of symptoms. This article reviews the current guidelines and evidence on the assessment and management of MPE. Assessment involves imaging techniques such chest X-ray and computed tomography (CT) scans, whilst thoracic ultrasound has a crucial role in guiding diagnostic procedures. Diagnostic pleural aspiration remains a cornerstone for establishing a tissue diagnosis, although its yield is variable depending on tumour type. Emergence of targeted immunotherapy has necessitated the need for large tissue samples for molecular testing, driving the need for pleural biopsies in relevant cases. Management encompasses therapeutic aspiration, chemical pleurodesis and indwelling pleural catheter insertion, each offering distinct benefits and considerations. Recent developments in equipment and combined approaches have enhanced patient outcomes and quality of life. The complexity of MPE requires a patient-centred approach to assessment and management and where possible patients should be managed with specialists in pleural disease on an outpatient basis.

Simultaneous detection of 10 cancer-associated amino acids and polyamines by high-performance liquid chromatography-high resolution mass spectrometry in pleural effusion cells obtained from lung adenocarcinoma patients

The deregulation of amino acid and polyamine metabolism is a hallmark of malignancy that regulates cancer cell proliferation, angiogenesis, and invasion. A sensitive mass spectrometry method was developed to simultaneously quantify 10 cancer-associated metabolites in pleural effusion cells for the diagnosis of malignancy and to complement conventional pleural cytology. Analytes were detected by high-performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) using C8-reversed-phase HPLC for separation and sequential window acquisition of all theoretical fragment ion spectra (SWATH) acquisition for obtaining high-resolution quantitative MS/MS chromatograms. This method was validated and applied to pleural effusion cells from patients with lung adenocarcinoma (LUAD, n = 48) and those from benign controls (n = 23). The range of the above metabolites was 2-200 ng/mL for proline, aspartate, ornithine, creatine, glutamine, glutamate, arginine, citrulline, and spermine and 10-1000 ng/mL for putrescine. The intra-assay and inter-assay coefficient of variation was below 13.70 % for all analytes. The joint detection of these metabolites in pleural effusion cells achieved a clinical sensitivity of 75.0 % and specificity of 95.7 % differentiating LUAD patients from benign controls. This assay enabled the detection of 10 cancer-associated metabolites in pleural effusion cells, and the increased concentration of these metabolites was correlated with the presence of LUAD.

Application of the international system for reporting serous fluid cytopathology on pleural effusion cytology with paired pleural biopsy: A new insight and novel approach on risk of malignancy

INTRODUCTION

The risk of malignancy (ROM) remains an area of interest for further evaluation in reporting systems including in International System for reporting serous fluid cytopathology (TIS), which is a standardized system for reporting effusion cytology. Herein, we report our findings in further investigation of ROM in TIS by studying on paired pleural effusion specimens and corresponding pleural biopsies with emphasis on negative for malignancy, and atypia of undetermined significance categories.

MATERIALS AND METHODS

The  Johns Hopkins Hospital pathology database was retrospectively searched for patients with a pleural biopsy (PBX) and a paired pleural effusion (PF) cytology specimens over a 4-year period. We employed the TIS categories. The following statistical parameters were evaluated: sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and ROM.

RESULTS

A total of 223 patient cases were included. Effusions TIS reclassification and ROM were as follows: 1.8% non-diagnostic (ROM 75%), 75.8% negative for malignancy (ROM 23%), 4.9% atypical cells of undetermined significance (ROM 45%), 2.2% suspicious for malignancy (ROM 80%), and 15.2% malignant (ROM 100%). Overall accuracy, sensitivity, specificity, PPV and NPV were calculated and were 79.4%, 45%, 97.7%, 91.2% and 77%, respectively. Among, discordant cases diagnosed negative for malignancy on PF and positive for malignancy on PBX, there were significant number of lymphomas, mesotheliomas, and sarcomas. Lung cancer was the most common carcinoma; however, rare types of carcinomas were noted. Cells blocks and immunohistochemistry (IHC) studies were utilized to confirm either malignant conditions or rule out malignancy in both cell blocks and histology biopsies.

CONCLUSION

This study demonstrates the high specificity and ROM for 'malignant' and 'suspicious for malignancy' categories in the TIS reporting system and highlights the modest negative predictive value for the 'negative for malignancy' category. Although Tissue biopsies are usually considered as 'gold standard', any definitive diagnosis of malignancy of body fluid should be considered positive for malignancy in further clinical decision-making.

Enhancing Intrapleural Hyperthermic Chemotherapy for Lung Cancer: Insights from 3D and PDX Models

Background/Objectives: Malignant pleural effusion (MPE) in lung cancer indicates systemically disseminated advanced lung cancer and is associated with poor survival. Intrapleural hyperthermic chemotherapy (IPHC) is a promising treatment for MPE; however, its biological basis is not fully understood. IPHC can enhance anticancer drug efficacy, particularly in drug-resistant cancers. This study investigated the effects of hyperthermia on cisplatin cytotoxicity in lung cancer cell lines, patient-derived tumor cells, and a patient-derived xenograft (PDX) model. Methods: Lung cancer cell lines (A549 and H2170) and patient-derived tumor cells were cultured in 2D/3D systems and treated with cisplatin under varying temperatures (37 °C, 43 °C, and 45 °C) and exposure times (5, 15, and 30 min). Antiproliferative effects were evaluated using LDH and CCK-8 assays. Optimal conditions identified in cell culture experiments were validated using a PDX model; tumor growth inhibition, delay, and protein expression were analyzed post-treatment. Results: Hyperthermia significantly enhanced the antitumor efficacy of cisplatin at 43 °C and 45 °C, with comparable effects under 15 and 30 min exposure. In the PDX model, IPHC showed increased tumor inhibition and necrosis and delayed tumor regrowth, particularly at higher cisplatin doses. Protein expression analysis revealed that hyperthermia decreased EGFR expression and increased levels of apoptosis-related proteins, including cleaved PARP and caspase-3. Conclusions: IPHC with cisplatin demonstrated enhanced antitumor efficacy in vitro models, particularly in drug-resistant lung cancer, indicating its potential as a valuable adjunct to existing treatment regimens for lung cancer and for improving patient outcomes in advanced lung cancer with MPE or pleural metastasis.

Malignant Pleural Effusion: A Multidisciplinary Approach

Malignant pleural effusion (MPE) has become an increasingly prevalent complication in oncological patients, negatively impacting their quality of life and casting a shadow over their prognosis. Owing to the pathophysiological mechanisms involved and the heterogeneous nature of the underlying disease, this entity is both a diagnostic and therapeutic challenge. Advances in the understanding of MPE have led to a shift in the treatment paradigm towards a more personalized approach. This article provides a comprehensive review and update on the pathophysiology of MPE and describes the diagnostic tools and the latest advances in the treatment of this complex clinical entity.

Can some inflammatory parameters predict the survival of patients with malignant pleural effusion?

Background

This study aimed to investigate whether there is a correlation between some serum inflammatory markers and the survival of patients with malignant pleural effusions (MPEs).

Methods

The prospective study included 125 patients (67 males, 58 females; median age: 62 years; range, 40 to 92 years) who underwent thoracentesis for pleural effusion between January 2020 and December 2021. An overall survival analysis was performed, and survival differences between the groups were investigated. The cutoff value of the inflammatory parameters associated with mortality was determined by receiver operating characteristic analysis.

Results

Median survival after detection of MPE was six months, and three- and five-year overall survivals were 16% and 4%, respectively. There was a significant correlation between the ECOG (Eastern Cooperative Oncology Group) score of the patients and the median survival. Serum C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), fluid albumin, and serum lactate dehydrogenase (LDH)-to-pleural LDH ratio and survival had a statistically significant relationship in receiver operating characteristic analysis. Threshold values were determined accordingly. Poor prognostic factors that were found to be statistically significant were high CRP (p=0.001), high NLR (p=0.001), high PLR (p=0.02), and high serum LDH-to-pleural LDH ratio (p=0.04).

Conclusion

Some serum inflammatory markers, including high CRP, high NLR, high PLR, and high serum LDH-to-pleural LDH ratio, can be a simple and inexpensive method in predicting prognosis in patients with MPE.

Evaluation of PD-1 and interleukin-10-receptor expression by T lymphocytes in malignant and benign pleural effusions

PD-1 (programmed cell death protein-1)/PD-L1 (programmed cell death ligand 1) as well as IL-10 (interleukin-10)/IL-10R (interleukin-10 receptor) interactions play a major role in tumor immune evasion in various malignancies. Several studies investigated the expression of PD-1 on T lymphocytes in pleural effusions (PE) in patients with malignant diseases. However, results in malignant pleural effusions (MPE) compared to benign PE (BPE) are underreported. In this prospective study, 51 patients (median age 66 years, IQR 54-78, 47% male) with PE of malignant or benign origin at the Medical University of Vienna between March 2021 and November 2022 were enrolled and divided into three groups according to the cytological results (group 1: MPE [n = 24, 47%]; group 2: BPE in malignant disease [n = 22, 43%]; group 3: BPE in benign disease [n = 5, 10%]). In the cytological samples, T cells were analyzed for the expression of PD-1 and IL-10R via flow cytometry. In MPE, the proportion of PD-1+ T lymphocytes on CD4+ cells was significantly lower than in BPE (40.1 vs. 56.3 in group 1 vs. 3, p = 0.019). Moreover, a significantly lower expression of PD-1+ IL-10R+ CD8+ (9.6 vs. 35.2 in group 1 vs. 2, p = 0.016; 9.6 vs. 25.0 in group 1 vs. 3, p = 0.032) and a significantly higher expression of PD-1-IL-10R-CD8+ T lymphocytes (43.7 vs. 14.0 in group1 vs. 2, p = 0.045; 43.7 vs. 23.3 in group 1 vs. 3, p = 0.032) were observed in MPE when compared to BPE. The frequency of T cells expressing PD-1 and IL-10R on CD8+ T cells is significantly lower in MPE compared to BPE regardless of the underlying disease indicating a different microenvironment in PE driven by the presence of tumor cells. Our observation spotlights the possible involvement of PD-1 and IL-10R in MPE.

Characterization of mesothelin gene expression in dogs and overexpression in canine mesotheliomas

Introduction

Canine mesotheliomas are uncommon malignant tumors typically detected late. Minimally invasive diagnostic biomarkers would facilitate diagnosis at earlier stages, thereby improving clinical outcomes. We hypothesized that mesothelin could be used as a reliable diagnostic biomarker for canine mesotheliomas since it has been used as a cancer biomarker for human mesothelioma. We aimed to explore and characterize mesothelin gene expression in dogs and assess its use as a diagnostic biomarker for canine mesotheliomas.

Materials and methods

We quantified expressed canine mesothelin transcripts via reverse transcription polymerase chain reaction (RT-PCR) and sequenced them using ribonucleic acid (RNA) extracted from a canine mesothelioma cell line. After confirming mesothelin expression, we assessed its levels in major organ tissues and compared them with those in the mesothelioma tissues using quantitative PCR (qPCR). Mesothelin overexpression in mesotheliomas was detected, and we further compared its levels using qPCR between mesotheliomas and non-mesotheliomas using tumor tissues and clinical sample effusions, confirming its significance as a diagnostic biomarker for canine mesothelioma.

Results

Mesothelin complementary deoxyribonucleic acid (cDNA) was amplified via RT-PCR, yielding a single band of expected upon DNA electrophoresis. Sequence analyses confirmed it as a predicted canine mesothelin transcript from the genome sequence database. Comparative sequence analysis of the deduced amino acid sequence of the expressed canine mesothelin demonstrated molecular signature similarities with the human mesothelin. However, the pre-sequence of canine mesothelin lacks the mature megakaryocyte potentiating factor (MPF) portion, which is typically cleaved post-translationally with furin. Mesothelin expression was quantified via qPCR revealing low levels in the mesothelial and lung tissues, with negligible expression in the other major organs. Canine mesothelin exhibited significantly higher expression in the canine mesotheliomas than in the noncancerous tissues. Moreover, analysis of clinical samples using qPCR demonstrated markedly elevated mesothelin expression in canine mesotheliomas compared to non-mesothelioma cases.

Discussion and conclusion

Canine mesothelin exhibits molecular and biological characteristics akin to human mesothelin. It could serve as a vital biomarker for diagnosing canine mesotheliomas, applicable to both tissue- and effusion-based samples.

The role of day-case thoracoscopy at a district general hospital: A real world observational study

Objective

To assess the feasibility and safety of talc pleurodesis performed as part of day-case medical thoracoscopy.

Methods

A Richard Wolf® 5 mm mini thoracoscope through a 5.5 mm port was used with eligible cases having talc poudrage followed by insertion of indwelling pleural catheter (IPC). District nurses drain the IPC daily for the first 5 days. Once the drain output is <150 mL, the frequency is progressively reduced to once weekly. The drain is removed after two consecutive dry taps 1 week apart.

Results

Overall, 51 patients underwent day-case thoracoscopy. Median time to removal of IPC for our day-case protocol was 14 days. There were seven deaths within 70 days among 41 patients with malignant pleural effusion in the day-case cohort, compared to eight deaths in the 33 conventional thoracoscopy controls. Overall, the day-case cohort observed a statistically significant reduction in all-cause mortality at 180 days compared to the conventional cohort (log rank p = 0.024). The average cost per patient of the day-case and inpatient cohort was £1,328.0 ± 106.0 and £1,835.0 ± 295.0 (p = 0.961).

Conclusion

This study suggests that thoracoscopy and talc poudrage can be performed safely as a day-case procedure. Further data are needed to ascertain long-term outcomes.

Talc slurry versus thoracoscopic talc insufflation for malignant pleural effusion: a systematic review and meta-analysis

OBJECTIVE

Talc pleurodesis is a widely used treatment option for malignant pleural effusion (MPE). However, the optimal form of administration remains controversial. Thus, we performed a systematic review and meta-analysis to assess the effectiveness of talc slurry (TS) in comparison with thoracoscopic talc insufflation/poudrage (TTI) for MPE treatment.

METHODS

We searched PubMed, EMBASE, and Cochrane Library databases for studies that compared TS with TTI in patients with MPE. We used a random-effects model with a 95% CI to pool the data. Heterogeneity was assessed with I2 statistics.

RESULTS

We included eight studies involving 1,163 patients, 584 of whom (50.21%) underwent TS. Pleurodesis failure rates were similar between the procedures (OR = 1.07; 95% CI: 0.56-2.06; p = 0.83; I2 = 62%); and 68% of patients (95% CI: 0.31-1.47; p = 0.33; I2 = 58%) had postoperative complications, which were lower in patients in the TS group than in the TTI group. In a subgroup analysis considering only randomized clinical trials, the failure rate was significantly lower in the TS treatment group (OR = 0.62; 95% CI: 0.42-0.90; p = 0.01; I2 = 0%). Similarly, dyspnea was less common in the TS group (OR = 0.74; 95% CI: 0.41-1.34; p = 0.32; I2 = 55%). Adverse effects were reported in 86 patients, and no significant difference was seen between the TS and TTI groups: empyema (OR = 1.43; 95% CI: 0.36-5.64; p = 0.86; I2 = 0%), pain (OR = 1.22 (95% CI: 0.67-2.21; p = 0.51; I2 = 38%), and pneumonia (OR = 1.15; 95% CI: 0.30-4.46; p = 0.86; I2 = 27%).

CONCLUSIONS

Our findings suggest that TS is an effective treatment for MPE, with no significant increase in adverse events. Results suggest equivalent efficacy and safety for both procedures.

The value of computed tomography-based radiomics for predicting malignant pleural effusions

Background

Malignant pleural effusion (MPE) is a common clinical problem that requires cytological and/or histological confirmation obtained by invasive examination to establish a definitive diagnosis. Radiomics is rapidly evolving and can provide a non-invasive tool to identify MPE.

Objectives

We aimed to develop a model based on radiomic features extracted from unenhanced chest computed tomography (CT) images and investigate its value in predicting MPE.

Method

This retrospective study included patients with pleural effusions between January 2016 and June 2020. All patients underwent a chest CT scanning and medical thoracoscopy after artificial pneumothorax. Cases were divided into a training cohort and a test cohort for modelling and verifying respectively. The Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) were applied to determine the optimal features. We built a radiomics model based on support vector machines (SVM) and evaluated its performance using ROC and calibration curve analysis.

Results

Twenty-nine patients with MPE and fifty-two patients with non-MPE were enrolled. A total of 944 radiomic features were quantitatively extracted from each sample and reduced to 14 features for modeling after selection. The AUC of the radiomics model was 0.96 (95% CI: 0.912-0.999) and 0.86 (95% CI: 0.657~1.000) in the training and test cohorts, respectively. The calibration curves for model were in good agreement between predicted and actual data.

Conclusions

The radiomics model based on unenhanced chest CT has good performance for predicting MPE and may provide a powerful tool for doctors in clinical decision-making.

CCL11/CCR3-dependent eosinophilia alleviates malignant pleural effusions and improves prognosis

Malignant pleural effusion (MPE) is a common occurrence in advanced cancer and is often linked with a poor prognosis. Eosinophils were reported to involve in the development of MPE. However, the role of eosinophils in MPE remains unclear. To investigate this, we conducted studies using both human samples and mouse models. Increased eosinophil counts were observed in patients with MPE, indicating that the higher the number of eosinophils is, the lower the LENT score is. In our animal models, eosinophils were found to migrate to pleural cavity actively upon exposure to tumor cells. Intriguingly, we discovered that a deficiency in eosinophils exacerbated MPE, possibly due to their anti-tumor effects generated by modifying the microenvironment of MPE. Furthermore, our experiments explored the role of the C-C motif chemokine ligand 11 (CCL11) and its receptor C-C motif chemokine receptor 3 (CCR3) in MPE pathology. As a conclusion, our study underscores the protective potential of eosinophils against the development of MPE, and that an increase in eosinophils through adoptive transfer of eosinophils or increasing their numbers improved MPE.

Development of a diagnostic algorithm to ascertain malignant pleural effusion utilizing clinical indicators and serum metal concentrations

Background

Malignant pleural effusion (MPE) is prevalent among cancer patients, indicating pleural metastasis and predicting poor prognosis. However, accurately identifying MPE in clinical settings is challenging. The aim of this study was to establish an innovative nomogram-derived model based on clinical indicators and serum metal ion levels to identify MPE.

Methods

From July 2020 to May 2022, 428 patients diagnosed with pleural effusion (PE) were consecutively recruited. Comprehensive demographic details, clinical symptoms, imaging data, pathological information, and laboratory results, including serum metal ion levels, were systematically collected. The nomogram was created by incorporating the most significant predictors identified through LASSO and multivariate logistic regression analysis. The predictors were assigned weighted points based on their respective regression coefficients, allowing for the calculation of a total score that corresponds to the probability of MPE. Internal validation using bootstrapping techniques assessed the nomogram's performance, including calibration, discrimination, and clinical applicability.

Results

Seven key variables were identified using LASSO regression and multiple regression analysis, including dyspnea, fever, X-ray/CT compatible with malignancy, pleural carcinoembryonic antigen(pCEA), serum neuron-specific enolase(sNSE), serum carcinoembryonic antigen(sCEA), and pleural lactate dehydrogenase(pLDH). Internal validation underscored the superior performance of our model (AUC=0.940). Decision curve analysis (DCA) analysis demonstrated substantial net benefit across a probability threshold range > 1%. Additionally, serum calcium and copper levels were significantly higher, while serum zinc levels were significantly lower in MPE patients compared to benign pleural effusion (BPE) patients.

Conclusion

This study effectively developed a user-friendly and reliable MPE identification model incorporating seven markers, aiding in the classification of PE subtypes in clinical settings. Furthermore, our study highlights the clinical value of serum metal ions in distinguishing malignant pleural effusion from BPE. This significant advancement provides essential tools for physicians to accurately diagnose and treat patients with MPE.

Establishing mesothelioma patient-derived organoid models from malignant pleural effusions

OBJECTIVES

Pleural mesothelioma is a cancer arising in the cells that line the lungs and chest wall with poor survival and poor response to first-line therapy. Organoid models of cancer can faithfully recapitulate the genetic and histopathological characteristics of individualized tumors and have potential to be used for precision medicine, however methods of establishing patient-derived mesothelioma organoids have not been well established in the published literature.

MATERIALS AND METHODS

Long-term mesothelioma patient-derived organoids were established from ten malignant pleural effusion fluids. Mesothelioma patient-derived organoids were compared to the corresponding biopsy tissue specimens using immunohistochemistry labelling for select diagnostic markers and the TruSight Oncology-500 sequencing assay. Cell viability in response to the chemotherapeutic drug cisplatin was assessed.

RESULTS

We established five mesothelioma patient-derived organoid cultures from ten malignant pleural effusion fluids collected from nine individuals with pleural mesothelioma. Mesothelioma patient-derived organoids typically reflected the histopathological and genomic features of patients' matched biopsy specimens and displayed cytotoxic sensitivity to cisplatin in vitro.

CONCLUSION

This is the first study of its kind to establish long-term mesothelioma organoid cultures from malignant pleural effusions and report on their utility to test individuals' chemotherapeutic sensitivities ex vivo.

A systematic review of patient-derived tumor organoids generation from malignant effusions

This review assesses the possibility of utilizing malignant effusions (MEs) for generating patient-derived tumor organoids (PDTOs). Obtained through minimally invasive procedures MEs broaden the spectrum of organoid sources beyond resection specimens and tissue biopsies. A systematic search yielded 11 articles, detailing the successful generation of 190 ME-PDTOs (122 pleural effusions, 54 malignant ascites). Success rates ranged from 33% to 100%, with an average of 84% and median of 92%. A broad and easily applicable array of techniques can be employed, encompassing diverse collection methods, variable centrifugation speeds, and the inclusion of approaches like RBC lysis buffer or centrifuged ME supernatants supplementation, enhancing the versatility and accessibility of the methodology. ME-PDTOs were found to recapitulate primary tumor characteristics and were primarily used for drug screening applications. Thus, MEs are a reliable source for developing PDTOs, emphasizing the need for further research to maximize their potential, validate usage, and refine culturing processes.

Expression of cytokines in pleural effusions and corresponding cell lines of small cell lung cancer

Background

Small cell lung cancer (SCLC) is a neuroendocrine aggressive tumor with a dismal prognosis due to the lack of curative therapeutic modalities. Approximately 11% of these patients show a malignant pleural effusion (MPE) that increase in frequency with progression of the disease. In MPE, fluid accumulates due to leaky vessels and mesothelial surfaces as well as impaired removal of fluid due to impaired drainage.

Methods

For this investigation, three SCLC MPE samples and supernatants of the corresponding isolated cell lines were analyzed for the content of 105 cytokines, chemokines, and growth factors. Overexpressed pathways including these cytokines were identified using Reactome analysis tools.

Results

A large range of cytokines, including vascular endothelial growth factor A (VEGFA), were found to be expressed in the MPEs and conditioned media of the corresponding cell line. These mediators are involved in pathways such as interleukin (IL) signaling, growth factor stimulation, modulation of cell adhesion molecules and proliferative cell signaling. Cytokine expression by the corresponding SCLC cell lines revealed the specific contributions of the tumor cells and included high expression of VEGFA, tumor-promoting factors and mediators exerting immunosuppressive and protumor effects. MPEs used here showed marked stimulation of the proliferation of four permanent SCLC cell lines.

Conclusions

MPEs comprise a large number of cytokines with mixed activities on tumor cells and the invading SCLC cells release a number of protumor mediators and induce an immunosuppressive pleural environment.

C5a enhances inflammation and chemotaxis of γδ T cells in malignant pleural effusion

BACKGROUND

The inhibitory effect of γδT17 cells on the formation of murine malignant pleural effusions (MPE) has been established. However, there is limited understanding regarding the phenotypic characterization of γδ T cells in MPE patients and their recruitment to the pleural cavity.

METHODS

We quantified γδ T cell prevalence in pleural effusions and corresponding peripheral blood from malignant and benign patients using immunohistochemistry and flow cytometry. The expression of effector memory phenotype, stimulatory/inhibitory/chemokine receptors and cytokines on γδ T cells in MPE was analyzed using multicolor flow cytometry. The infiltration of γδ T cells in MPE was assessed through immunofluorescence, ELISA, flow cytometry and transwell migration assay.

RESULTS

We observed a significant infiltration of γδ T cells in MPE, surpassing the levels found in blood and benign pleural effusion. γδ T cells in MPE exhibited heightened expression of CD56 and an effector memory phenotype, while displaying lower levels of PD-1. Furthermore, γδ T cells in MPE showed higher levels of cytokines (IFN-γ, IL-17A and IL-22) and chemokine receptors (CCR2, CCR5 and CCR6). CCR2 expression was notably higher in the Vδ2 subtype compared to Vδ1 cells. Moreover, the complement C5a enhanced cytokine release by γδ T cells, upregulated CCR2 expression in Vδ2 subsets, and stimulated the production of chemokines (CCL2, CCL7 and CCL20) in MPE. In vitro utilizing CCR2 neutralising and C5aR antagonist significantly reduced the recruitment of γδ T cells.

CONCLUSIONS

γδ T cells infiltrate MPE by overexpressing CCR2 and exhibit hightened inflammation, which is further augmented by C5a.

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.

Ultrasound in the Diagnosis of Non-Expandable Lung: A Prospective Observational Study of M-Mode, B-Mode, and 2D-Shear Wave Elastography

BACKGROUND

Non-expandable lung (NEL) has severe implications for patient symptoms and impaired lung function, as well as crucial implications for the management of malignant pleural effusion (MPE). Indwelling pleural catheters have shown good symptom relief for patients with NEL; hence, identifying patients early in their disease is vital. With the inability of the lung to achieve pleural apposition following thoracentesis and the formation of a hydropneumothorax, traditionally, chest X-ray and clinical symptoms have been used to make the diagnosis following thoracentesis. It is our aim to investigate whether ultrasound measurement of lung movement during respiration can predict NEL before thoracentesis, thereby aiding clinicians in their planning for the optimal treatment of affected patients.

METHODS

A total of 49 patients were consecutively included in a single-centre trial performed at a pleural clinic. Patients underwent protocolled ultrasound assessment pre-thoracentesis with measurements of lung and diaphragm movement and shear wave elastography measurements of the pleura and pleural effusion at the planned site of thoracentesis.

RESULTS

M-mode measurements of lung movement provided the best diagnostic ROC-curve results, with an AUC of 0.81. Internal validity showed good results utilising the calibration belt test and Brier test.

CONCLUSION

M-mode measurement of lung movement shows promise in diagnosing NEL before thoracentesis in patients with known or suspected MPE. A validation cohort is needed to confirm the results.

[Treatment of malignant effusion]

Malignant effusion complicates more than 15% of all cancers in delayed stages of progression. The most common causes of metastatic pleuritis are lung cancer, breast cancer, ovarian cancer, lymphoproliferative diseases or dissemination of gastrointestinal tumors. Malignant effusion is associated with negative prognosis for overall survival regardless of etiology of tumor, significantly complicates the course of the underlying disease, impairs life quality and complicates treatment. Despite various methods for pleural cavity obliteration in recurrent metastatic pleuritis, there is still no a uniform approach to choosing the optimal treatment strategy. We analyzed the main methods of conservative and surgical treatment of recurrent metastatic pleuritic regarding efficacy, risk of recurrence and reproducibility.

Malignant pleural disease

Malignant pleural disease represents a growing healthcare burden. Malignant pleural effusion affects approximately 1 million people globally per year, causes disabling breathlessness and indicates a shortened life expectancy. Timely diagnosis is imperative to relieve symptoms and optimise quality of life, and should give consideration to individual patient factors. This review aims to provide an overview of epidemiology, pathogenesis and suggested diagnostic pathways in malignant pleural disease, to outline management options for malignant pleural effusion and malignant pleural mesothelioma, highlighting the need for a holistic approach, and to discuss potential challenges including non-expandable lung and septated effusions.

Chemosensitivity of three patient-derived primary cultures of canine pericardial mesothelioma by single-agent and combination treatment

INTRODUCTION

Canine mesothelioma is a rare malignant tumor that mostly affects body cavities, such as the pericardial and pleural cavities. Chemotherapy plays a crucial role in the treatment of canine mesotheliomas. We aimed to compare the antitumor effects of single-agent and combination chemotherapeutic agents on patient-derived primary cultures of canine pericardial mesothelioma established in this study. We planned to generate xenograft models for future studies.

MATERIAL AND METHODS

Effusion samples were collected from three dogs with histologically diagnosed pericardial mesothelioma and used for primary culture. Cultured cells were characterized by immunostaining for pan-cytokeratin AE1/AE3, vimentin, Wilms' tumor suppressor gene 1 (WT1), and cytokeratin 5 (CK5). To assess the tumorigenic properties of cells in the effusion and generate a xenograft model, the cell suspension was injected into a severe combined immunodeficient (SCID) mouse either subcutaneously (SC) or intraperitoneally (IP). Lastly, chemosensitivity of established primary cultures against four drugs, doxorubicin, vinorelbine, carboplatin, and gemcitabine, by single-agent treatment as well as combination treatment of carboplatin at a fixed concentration, either 10 or 100 μM, and gemcitabine at different concentrations ranging from 0-1000 μM was assessed by cell viability assay.

RESULTS

Primary cultures were successfully generated and characterized by dual positivity for AE1/AE3 and vimentin and positive staining for WT-1 and CK5, confirming the mesothelial origin of the cells. In the xenograft models, SC mouse developed a subcutaneous mass, whereas IP mouse developed multiple intraperitoneal nodules. The masses were histopathologically consistent with mesotheliomas. The chemosensitivity assay revealed that carboplatin had the highest anti-tumor effects among the four tested single-agent treatments. Furthermore, carboplatin at 100 μM combined with gemcitabine at clinically relevant doses demonstrated the augmented anti-tumor effects compared to single-agent treatment.

DISCUSSION AND CONCLUSION

Primary cultures and xenograft models generated in this study could be useful tools for in vitro and in vivo studies of canine mesothelioma. Carboplatin is a highly effective chemotherapeutic agent against canine mesothelioma when used as a sole agent and in combination with gemcitabine.

Cost Comparison of Treatment Alternatives for Pleural Effusion and Ascites from a Payer Perspective: Are There Cost Savings from Indwelling Catheters?

Background: The presence of pleural effusions and ascites in patients is often considered a marker of illness severity and a poor prognostic indicator. This study aims to compare inpatient and outpatient costs of alternative invasive treatments for ascites and pleural effusions. Methods: The retrospective single-institution study included inpatient cases treated for pleural effusion (J90 and J91) or ascites (R18) at the University Hospital Cologne (UHC) in Germany between January 01, 2020, and December 31, 2021. Costs for punctures and indwelling catheter systems (ICSs) as well as pleurodesis were analyzed in different comparator treatment pathways. Real-world data from the UHC tertiary care center were based on diagnosis-related group fees from 2020 to 2021. A simulation of outpatient expenses was carried out to compare inpatient and outpatient costs for each pathway from a payer perspective. Results: A total of 4323 cases (3396 pleural effusions and 1302 ascites) were analyzed. For ascites, inpatient implantation with home care drainage was found to be the most expensive option, with total costs of €1,918.58 per procedure, whereas outpatient puncture was the least expensive option at €60.02. For pleural effusions, the most expensive treatment pathway was pleurodesis at €8,867.84 compared with the least costly option of outpatient puncture resulting in total costs per procedure of €70.03. A break-even analysis showed that outpatient puncture remains the most inexpensive treatment option, and the ICS comprises a cost-saving potential. Longevity of several months with the use of ICSs results in both enhanced quality of life for patients and increased cost savings.

Clinical importance of serum and pleural fluid prominin-1 and hypoxia-inducible factor-1α concentration in the evaluation of lymph node involvement in patients with malignant pleural effusion

Introduction

Malignant pleural effusion (MPE) and lymph node metastasis (LNM) presence are poor prognostic factors that have importance for cancer patients. The study objective was to determine whether hypoxia-inducible factor-1α (HIF-1α) and prominin-1 (CD133) in pleural fluid (P) and serum (S) could be used as biomarkers for diagnosis of lymph node involvement in patients with MPE.

Materials and methods

Fifty-six patients with MPE and 30 healthy control subjects were included. Computerized tomography (CT) and positron emission tomography (PET) were used to diagnose pleural effusion. Patients with malignant cells in pleural fluid cytological examination were included in the MPE group. Thirty-five patients with lymph node metastases on CT were included in the LNM-positive MPE group. Serum and pleural fluid HIF-1α and CD-133 concentrations were measured manually via enzyme-linked immunosorbent assay (ELISA).

Results

Serum concentrations of HIF-1α and CD133 were higher in MPE patients. It was found that CD133/HIF-1α (S) ratio was higher in the malignant patient group with positive lymph node involvement than in the negative group, while concentrations of HIF-1α (P) were lower. Pleural fluid HIF-1α and CD133/HIF-1α (S) ratio had sufficient performance in diagnosing lymphatic metastases in patients with MPE (AUC = 0.90 and 0.83, respectively).

Conclusions

In conclusion, serum HIF-1α and CD133 concentrations were higher in patients with MPE, consistent with our hypothesis. Concentrations of HIF-1α (P) and CD133/HIF-1α (S) ratio can be used as biomarkers in diagnosing lymph node involvement in MPE patients, according to this experiment.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

The International System for Reporting Serous Fluid Cytopathology: An Institutional Experience on its Implication and Assessment of Risk of Malignancy in Effusion Cytology

Background

The "international system for reporting serous fluid cytopathology"(TIS) consists of five diagnostic categories: nondiagnostic (ND), negative for malignancy (NFM), atypia of undetermined significance (AUS), suspicious for malignancy (SFM), and malignant (MAL). The study was conducted to reclassify effusion cytology samples according to the newly proposed TIS to calculate the risk of malignancy (ROM) for each category and to conduct performance analysis.

Materials and Methods

The study was a retrospective observational study conducted at a tertiary care institution in North India. Clinical data of the cases from June 2013 to July 2021 were retrieved and the cases were reviewed by two cytopathologists. All cases were reclassified according to the proposed TIS system into five categories.

Results

A total of 2318 patients were included in the study over a time span of 8 years, and 1614 (69.6%) cases of pleural effusion cytology, 612 (26.4%) cases of peritoneal effusion cytology, and 92 (3.9%) cases of pericardial effusion cytology were included. All effusion cytology smears were recategorized as per TIS guidelines into ND, NFM, AUS, SFM, and MAL with 4 (0.17%), 1756 (75.75%), 12 (0.51%), 57 (2.46%), and 489 (21.11%) cases, respectively, and ROM was 25%, 17.9%, 66.7%, 75.4%, and 96.5%, respectively, for the categories.

Conclusion

Besides being a simple, easy, and user-friendly system, TIS has the benefit of risk stratification and ROM for each category. The TIS system proposed a tiered scheme, which places the effusion cytology into well-defined categories, and therefore has lesser chances of false-positive and false-negative cases.

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.

Immunoassay with Novel Paired Antibodies for Detection of Lipoarabinomannan in the Pleural Fluid and Plasma of Patients with Tuberculous Pleurisy

Tuberculous pleurisy (TP) is one of the most common forms of extrapulmonary tuberculosis, but its diagnosis is challenging. Lipoarabinomannan (LAM) antigen is a biomarker for Mycobacterium tuberculosis (Mtb) infection. LAM detection has potential as an auxiliary diagnostic method for TP. We have successfully generated five rabbit anti-LAM monoclonal antibodies (BJRbL01, BJRbL03, BJRbL20, BJRbL52, and BJRbL76). Here, anti-LAM antibodies were tested to detect LAM in the pleural fluid and plasma of patients with TP by sandwich enzyme-linked immunosorbent assays (ELISAs). The results revealed that all of the anti-LAM antibodies were successfully used as capture and detection antibodies in sandwich ELISAs. The BJRbL01/BJRbL01-Bio pair showed better performance than the other antibody pairs for detecting mycobacterial clinical isolates and had a limit of detection of 62.5 pg/mL for purified LAM. LAM levels were significantly higher in the pleural fluid and plasma of patients with TP than in those of patients with malignant pleural effusion or the plasma of non-TB, and LAM levels in the pleural fluid and plasma were positively correlated. Moreover, LAM levels in the pleural fluid sample were significantly higher in confirmed TP patients than in clinically diagnosed TP patients. Our studies provide novel LAM detection choices in the pleural fluid and plasma of TP patients and indicate that LAM detection assay has an auxiliary diagnostic value for TP, which may help to improve the diagnosis of TP.

Small Cell Lung Cancer and Pleural Effusion: An Analysis from a District General Hospital

INTRODUCTION

The incidence of malignant pleural effusion (MPE) in patients with small cell lung cancer (SCLC) in an American population is approximately 11%, and overall survival in that group is 3 months (compared to 7 months without an effusion. To our knowledge, no study has been done in the United Kindgom and we thus sought to determine the characteristics of the local population.

METHOD

All patients coded as having small cell lung cancer from Somerset register from January 2012-September 2021 were reviewed. We excluded those with indeterminate pathology reports, carcinoid or large cell neuroendocrine cancers. Basic demographics, presence of an MPE and any interventions and outcomes were collected for descriptive analysis. Continuous variables are presented as mean (±) range, median (± IQR) when outliers were present and categorical variables as percentages where appropriate. Caldicott reference C3905.

RESULTS

Four hundred one patients with SCLC were identified (11% of all patients, median time to death from presentation 208 days, IQR 304 [many outliers); 224 (55.9%) were female, 177 male [median age 75 years, IQR 13]. One hundred seven (27%) presented with an effusion: 23 were sampled, 10 had positive cytology, all were exudates, 8 required chest drainage, the mean performance status (PS) was 2 (range 1-4) and the median time to death 142 days, IQR 45. Of the 294 with no initial effusions, 70 (24%) developed a pleural effusion with progressive disease (mean PS 1, median age 71.5 years, IQR 14, median to death 327 days, IQR 395, 1 outlier); 224 patients never had a MPE with a median time to death of 212 days, IQR 305, multiple outliers and, when compared to those with a MPE at any point, median time to death was 211 days, IQR 295.5 (multiple outliers).

CONCLUSION

Meaningful analysis was difficult because of the presence of multiple outliers in values collected and not correcting for stage at presentation or treatment modalities and previous studies did not correct for those either. Those presenting with an MPE had a poorer prognosis, probably signifying advanced disease and the presence of MPE in our SCLC cohort seems higher. Large prospective databases for this are required.

Single-cell RNA sequencing captures patient-level heterogeneity and associated molecular phenotypes in breast cancer pleural effusions

BACKGROUND

Malignant pleural effusions (MPEs) are a common complication of advanced cancers, particularly those adjacent to the pleura, such as lung and breast cancer. The pathophysiology of MPE formation remains poorly understood, and although MPEs are routinely used for the diagnosis of breast cancer patients, their composition and biology are poorly understood. It is difficult to distinguish invading malignant cells from resident mesothelial cells and to identify the directionality of interactions between these populations in the pleura. There is a need to characterize the phenotypic diversity of breast cancer cell populations in the pleural microenvironment, and investigate how this varies across patients.

METHODS

Here, we used single-cell RNA-sequencing to study the heterogeneity of 10 MPEs from seven metastatic breast cancer patients, including three Miltenyi-enriched samples using a negative selection approach. This dataset of almost 65 000 cells was analysed using integrative approaches to compare heterogeneous cell populations and phenotypes.

RESULTS

We identified substantial inter-patient heterogeneity in the composition of cell types (including malignant, mesothelial and immune cell populations), in expression of subtype-specific gene signatures and in copy number aberration patterns, that captured variability across breast cancer cell populations. Within individual MPEs, we distinguished mesothelial cell populations from malignant cells using key markers, the presence of breast cancer subtype expression patterns and copy number aberration patterns. We also identified pleural mesothelial cells expressing a cancer-associated fibroblast-like transcriptomic program that may support cancer growth.

CONCLUSIONS

Our dataset presents the first unbiased assessment of breast cancer-associated MPEs at a single cell resolution, providing the community with a valuable resource for the study of MPEs. Our work highlights the molecular and cellular diversity captured in MPEs and motivates the potential use of these clinically relevant biopsies in the development of targeted therapeutics for patients with advanced breast cancer.

Characterization of the pleural microenvironment niche and cancer transition using single-cell RNA sequencing in EGFR-mutated lung cancer

Background: Lung cancer is associated with a high mortality rate and often complicated with malignant pleural effusion (MPE), which has a very poor clinical outcome with a short life expectancy. However, our understanding of cell-specific mechanisms underlying the pathobiology of pleural metastasis remains incomplete. Methods: We analyzed single-cell transcriptomes of cells in pleural effusion collected from patients with lung cancer and congestive heart failure (as a control), respectively. Soluble and complement factors were measured using a multiplex cytokine bead assay. The role of ferroptosis was evaluated by GPX4 small interfering RNA (siRNA) transfection and overexpression. Results: We found that the mesothelial-mesenchymal transition (MesoMT) of the pleural mesothelial cells contributed to pleural metastasis, which was validated by lung cancer/mesothelial cell co-culture experiments. The ferroptosis resistance that protected cancer from death which was secondary to extracellular matrix detachment was critical for pleural metastasis. We found a universal presence of immune-suppressive lipid-associated tumor-associated macrophages (LA-TAMs) with complement cascade alteration in the MPE of the lung cancer patients. Specifically, upregulated complement factors were also found in the MPE, and C5 was associated with poor overall survival in the lung cancer patients with epidermal growth factor receptor mutation. Plasmacytoid dendritic cells (pDCs) exhibited a dysfunctional phenotype and pro-tumorigenic feature in the primary cancer. High expression of the gene set extracted from pDCs was associated with a poor prognosis in the lung cancer patients. Receptor-ligand interaction analysis revealed that the pleural metastatic niche was aggravated by cross-talk between mesothelial cells-cancer cells/immune cells via TNC and ICAM1. Conclusions: Taken together, our results highlight cell-specific mechanisms involved in the pathobiological development of pleural metastasis in lung cancer. These results provide a large-scale and high-dimensional characterization of the pleural microenvironment and offer a useful resource for the future development of therapeutic drugs in lung cancer.

Comparison between different treatment regimens of vascular targeting drug to malignant pleural effusion in patients with lung cancer: A Bayesian network meta-analysis

BACKGROUND

The presence of malignant pleural effusion in lung cancer patients often suggests a poor prognosis. We plan to investigate which regimen of vascular targeting drug is preferable to control the malignant pleural effusion in such patients.

METHODS

Two investigators dependently searched and screened for randomized controlled trials in PubMed, Embase, Web of Science and China National Knowledge Infrastructure from the database inception to August 2022. R software was applied to build a network model in Bayesian method. Objective response rate of malignant pleural effusion is the primary outcome measure. Besides, the incidence of 3 adverse events were compared, including gastrointestinal reaction, leukopenia and hypertension. Due to the disconnection of network, we analysis and discuss the short-term treatment (3-4 weeks) and long-term treatment (6-12 weeks) respectively.

RESULTS

31 studies with 2093 patients were identified. Four targeting drugs contain bevacizumab (Bev), anlotinib, apatinib and Endostar. Two administration routes include intracavity perfusion (icp) and intravenous injection. Based on the current evidence, for short-term treatments, compared with single-agent chemotherapy (CT), Bev_icp + CT, anlotinib + CT, Bev_icp and anlotinib + endorstar_icp present better objective response, and no statistical significance was found in objective response between Bev_icp + CT, anlotinib + CT and Bev_icp. For long-term treatments, compared with doublet or triplet chemotherapy (2CT or 3CT), Bev_icp + 2CT, apatinib + 2CT, Bev_icp + 3CT, and Bev_intravenous injection + 2CT are more effective option, but no statistical significance was found in objective response between the 4 combination regimens with chemotherapy.

CONCLUSION

Our findings suggest that no statistical significance between above vascular targeting regimens. Pathological type of lung cancer may affect the effect of bevacizumab intracavity infusion plus chemotherapy. The influence of different administration routes of vascular targeting drugs on efficacy remains to be investigated. There are some concerns with the quality of the studies, and some limitations should be considered when interpreting these results, which includes limited geographical region and sample size of studies. Despite these limitations, this study may inform vascular targeting therapy choice in such a patient population.

Do interventions for malignant pleural effusions impact on patient reported fatigue levels?

BACKGROUND

Malignant pleural effusions (MPEs) are common. They are associated with a poor prognosis and high symptom burden. Previous studies have focused primarily on breathlessness.

AIM

To evaluate whether interventions to treat MPEs impact on fatigue levels and to test the feasibility of the methodology.

METHODS

A prospective pilot study was conducted at a single Trust's adult pleural service over a 7 month period. It used a validated outcome measure, Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) to assess fatigue levels pre-intervention for MPE, which was repeated at 7, 14 and 30 days intervals. Data were gathered on patient demographics and potential confounding factors. The feasibility of the methodology was assessed. Recruitment targets had to be revised due to the COVID-19 pandemic.

RESULTS

Mean age was 73 years (range 44 to 88), with a predominance of lung cancer and mesothelioma (n=16/25). Patients were willing to participate and the methodology appeared acceptable. High attrition rate was due to deteriorating participant health, rather than unacceptability of study design. For those who completed 30-day follow up (n=11/25), there was an improvement in fatigue scores. The majority of patients screened were recruited to the trial.

CONCLUSION

This study met its aims in confirming the acceptability of the study protocol and suggested that intervention for MPE improved fatigue levels. However, the sample size was small and a further larger statistically powered study should be undertaken before conclusions can be drawn to influence clinical practice.

Outcomes for Malignant Pleural Effusions Because of Melanoma Treated With Indwelling Pleural Catheters

BACKGROUND

Indwelling pleural catheters (IPCs) reduce dyspnea and improve quality of life in patients with malignant pleural effusions (MPEs). Data on outcomes of MPEs secondary to metastatic melanoma managed with IPCs are scarce. We aimed to evaluate outcomes of patients receiving IPCs for MPEs secondary to melanoma compared with other malignancies.

METHODS

We identified patients from our prospectively collected database of all patients who had an IPC insertion for MPEs at our tertiary care center for melanoma between May 2006 and November 2018 and for nonmelanoma between May 2006 and June 2013. Chart reviews were conducted to obtain patient demographics, catheter complications, time of IPC removal or death, x-ray imaging, and pleural fluid characteristics.

RESULTS

We identified 27 MPEs because of melanoma and 1114 because of nonmelanoma malignancies treated with IPC. The most frequent complication was pleural fluid loculation requiring fibrinolytics which was significantly higher in the melanoma (14.8%) compared with the nonmelanoma group (3.8%; P =0.02). Cumulative incidence functions for catheter removal ( P =0.8) or death with catheter in situ ( P =0.3) were not significant between melanoma and nonmelanoma groups in competing risk analysis. Baseline radiographic pleural effusion scores were similar, but became significantly higher (increased pleural opacity) in the melanoma group at time points following IPC insertion ( P <0.05).

CONCLUSION

MPEs because of melanoma had a higher rate of loculations requiring fibrinolytics and less radiographic improvement after IPC insertion suggesting this patient subgroup has a more complicated pleural space which may be less responsive to drainage.

Clinical predictors and outcomes of non-expandable lung following percutaneous catheter drainage in lung cancer patients with malignant pleural effusion

Non-expandable lung (NEL) often occurs during pleural fluid drainage in patients with malignant pleural effusion (MPE). However, data regarding the predictors and prognostic impact of NEL on primary lung cancer patients with MPE receiving pleural fluid drainage, compared to malignant pleural mesothelioma (MPM), are limited. This study was aimed to investigate the clinical characteristics of lung cancer patients with MPE developing NEL following ultrasonography (USG)-guided percutaneous catheter drainage (PCD) and compare the clinical outcomes between those with and without NEL. Clinical, laboratory, pleural fluid, and radiologic data and survival outcomes of lung cancer patients with MPE undergoing USG-guided PCD were retrospectively reviewed and compared between those with and without NEL. Among 121 primary lung cancer patients with MPE undergoing PCD, NEL occurred in 25 (21%). Higher pleural fluid lactate dehydrogenase (LDH) levels and presence of endobronchial lesions were associated with development of NEL. The median time to catheter removal was significantly extended in those with NEL compared to those without (P = .014). NEL was significantly associated with poor survival outcome in lung cancer patients with MPE undergoing PCD, along with poor Eastern Cooperative Oncology Group (ECOG) performance status (PS), the presence of distant metastasis, higher serum C-reactive protein (CRP) levels, and not receiving chemotherapy. NEL developed in one-fifth of lung cancer patients undergoing PCD for MPE and was associated with high pleural fluid LDH levels and the presence of endobronchial lesions. NEL may negatively affect overall survival in lung cancer patients with MPE receiving PCD.

Arsenic Inhibits Proliferation and Induces Autophagy of Tumor Cells in Pleural Effusion of Patients with Non-Small Cell Lung Cancer Expressing EGFR with or without Mutations via PI3K/AKT/mTOR Pathway

To clarify whether arsenic could exert inhibitory effects on tumor cells in pleural effusions of patients with non-small cell lung cancer (NSCLC), 36 NSCLC pleural effusion samples were collected from Changzheng Hospital and Ruijin Hospital, from 2019 to 2022. The genotype of epidermal growth factor receptor (EGFR) was identified. Tumor cells were isolated and treated with arsenic trioxide (ATO) or/and gefitinib. Additionally, six patients were intrapleurally administrated with ATO. Results showed that 25 samples bore EGFR wild type (WT) and 11 harbored EGFR mutations, including 6 with L858R, 3 with ΔE746-A750, and 2 with T790M. ATO diminished the number of tumor cells from patients with WT and mutant EGFR, down-regulated the expression or phosphorylation of EGFR, pmTOR, PI3K, PTEN, and p4E-BP1, and up-regulated the expression of LC3. Immunofluorescent experiments showed that ATO enhanced LC3 and P62. By contrast, gefitinib was only effective in those harboring EGFR sensitizing mutations. Notably, in patients with intrapleural ATO injection, the pleural effusion underwent a bloody to pale yellow color change, the volume of the pleural effusion was reduced, and the number of the tumor cells was significantly reduced. In conclusion, arsenic is effective against NSCLC with various EGFR genotypes in vitro and in vivo, and potentially circumvents gefitinib resistance.

Resectability in bronchogenic carcinoma: A single‑center experience

Bronchogenic carcinoma comprises >90% of primary lung tumors. The present study aimed to estimate the profile of patients with bronchogenic carcinoma and assess the cancer resectability in newly diagnosed patients. This is a single-center retrospective review conducted over a period of 5 years. A total of 800 patients with bronchogenic carcinoma were included. The diagnoses were mostly proven with either cytological examination or histopathological diagnosis. Sputum analysis, cytological examination of pleural effusion and bronchoscopic examination were performed. Lymph node biopsy, minimally invasive procedures (mediastinoscopy and video-assisted thoracoscopic surgery), tru-cut biopsy or fine-needle aspiration was used to obtain the samples for diagnosis. The masses were removed by lobectomy and pneumonectomy. The age range was between 22 and 87 years, with a mean age of 62.95 years. Males represented the predominant sex. Most of the patients were smokers or ex-smokers. The most common symptom was a cough, followed by dyspnea. Chest radiography revealed abnormal findings in 699 patients. A bronchoscopic evaluation was performed for the majority of patients (n=633). Endobronchial masses and other suggestive malignancy findings were present in 473 patients (83.1%) of the 569 who underwent fiberoptic bronchoscopy. Cytological and/or histopathological samples of 581 patients (91.8%) were positive. Small cell lung cancer (SCLC) occurred in 38 patients (4.75%) and non-SCLC was detected in 762 patients (95.25%). Lobectomy was the main surgical procedure, followed by pneumonectomy. A total of 5 patients developed postoperative complications without any mortality. In conclusion, bronchogenic carcinoma is rapidly increasing without a predilection for sex in the Iraqi population. Advanced preoperative staging and investigation tools are required to determine the rate of resectability.

Impact of a Dedicated Pleural Clinic on Indwelling Pleural Catheter Related Outcomes: A Retrospective Single Center Experience

BACKGROUND

Recurrent pleural effusions are a major cause of morbidity and frequently lead to hospitalization. Indwelling pleural catheters (IPCs) are tunneled catheters that allow ambulatory intermittent drainage of pleural fluid without repeated thoracentesis. Despite the efficacy and safety of IPCs, data supporting postplacement follow-up is limited and variable. Our study aims to characterize the impact of a dedicated pleural clinic (PC) on patient outcomes as they relate to IPCs.

METHODS

Patients who underwent IPC placement between 2015 and 2021 were included in this retrospective study. Differences in outcomes were analyzed between patients with an IPC placed and managed by Interventional Pulmonology (IP) through the PC and those placed by non-IP services (non-PC providers) before and after the PC implementation.

RESULTS

In total, 371 patients received IPCs. Since the implementation of the PC, there was an increase in ambulatory IPC placement (31/133 pre-PC vs. 96/238 post-PC; P =0.001). There were fewer admissions before IPC placement (18/103 vs. 43/133; P =0.01), and fewer thoracenteses per patient (2.7±2.5 in PC cohort vs. 4±5.1 in non-PC cohort; P <0.01). The frequency of pleurodesis was higher in the PC cohort (40/103 vs. 41/268; P <0.001). A Fine and Gray competing risks model indicated higher likelihood of pleurodesis in the PC cohort (adjusted subhazard ratio 3.8, 95% CI: 2.5-5.87).

CONCLUSION

Our experience suggests that the implementation of a dedicated PC can lead to improved patient outcomes including fewer procedures and admissions before IPC placement, and increased rates of pleurodesis with IPC removal.