Malignant pleural effusion: from bench to bedside

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.

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.

Amino Acid-Metabolizing Enzymes in Advanced High-Grade Serous Ovarian Cancer Patients: Value of Ascites as Biomarker Source and Role for IL4I1 and IDO1

The molecular mechanisms contributing to immune suppression in ovarian cancer are not well understood, hampering the successful application of immunotherapy. Amino acid-metabolizing enzymes are known to contribute to the immune-hostile environment of various tumors through depletion of amino acids and production of immunosuppressive metabolites. We aimed to collectively evaluate the activity of these enzymes in high-grade serous ovarian cancer patients by performing targeted metabolomics on plasma and ascites samples. Whereas no indication was found for enhanced l-arginine or l-glutamine metabolism by immunosuppressive enzymes in ovarian cancer patients, metabolism of l-tryptophan by indoleamine 2,3-dioxygenase 1 (IDO1) was significantly elevated compared to healthy controls. Moreover, high levels of l-phenylalanine- and l-tyrosine-derived metabolites associated with interleukin 4 induced 1 (IL4I1) activity were found in ovarian cancer ascites samples. While l-tryptophan is a major substrate of both IDO1 and IL4I1, only its enhanced conversion into l-kynurenine by IDO1 could be detected, despite the observed activity of IL4I1 on its other substrates. In ascites of ovarian cancer patients, metabolite levels were higher compared to those in plasma, demonstrating the value of utilizing this fluid for biomarker identification. Finally, elevated metabolism of l-phenylalanine and l-tyrosine by IL4I1 correlated with disease stage, pointing towards a potential role for IL4I1 in ovarian cancer progression.

Factors Affecting Rate of Pleural Fluid Accumulation in Patients with Malignant Pleural Effusions

Purpose of Review

Malignant pleural effusions (MPEs) are initially treated with thoracocentesis but usually reaccumulate. There is wide variation in the rate of recurrence. Those with rapid recurrence could benefit from early definitive treatment, whilst those with slower recurrences may not. Here, we discuss pleural fluid homeostasis, MPE pathophysiology, and factors associated with reaccumulation.

Recent Findings

Few studies have investigated markers of MPE reaccumulation. Suggested features of rapid reaccumulation include lactate dehydrogenase, effusion size, positive cytology, and dyspnoea. Vascular endothelial growth factor (VEGF) correlates with MPE size and treatment response, but its association with reaccumulation rate is unknown. Some anti-VEGF therapies have shown promise in MPE management.

Summary

Further work is needed to validate hypothesised biomarkers of rapid recurrence and to characterise other biomarkers, such as VEGF. The Reaccumulation rate of Malignant Pleural Effusions After Therapeutic Aspiration (REPEAT) study aims to address these gaps in the literature and is currently in recruitment.

DNA Methylation Analysis of the SHOX2 and RASSF1A Panel Using Cell-Free DNA in the Diagnosis of Malignant Pleural Effusion

Objectives

The differential diagnosis of pleural effusion (PE) is a common but major challenge in clinical practice. This study aimed to establish a strategy based on a PE-cell-free DNA (cfDNA) methylation detection system for the differential diagnosis of malignant pleural effusion (MPE) and benign pleural effusion (BPE).

Methods

A total of 104 patients with PE were enrolled in this study, among which 50 patients had MPE, 9 malignant tumor patients had PE of indefinite causes, and the other 45 patients were classified as benign controls. The methylation status of short stature homeobox 2 (SHOX2) and RAS association domain family 1, isoform A (RASSF1A) was detected using PE-cfDNA specimens by real-time fluorescence quantitative PCR. Total methylation (TM) was defined as the combination of the methylation levels of SHOX2 and RASSF1A. The electrochemiluminescence immunoassay was applied to evaluate the levels of multiple serum tumor markers.

Results

The PE-cfDNA methylation status of either SHOX2 or RASSF1A was much higher in MPE samples than in benign controls. The combination of SHOX2 and RASSF1A methylation in PE yielded a diagnostic sensitivity of 96% and a specificity of 100%, respectively. When compared with the corresponding serum tumor marker detection results, TM showed the highest diagnostic efficiency (AUC = 0.985). Furthermore, the combination of the SHOX2 and RASSF1A methylation panels using PE-cfDNA could apparently improve the differential diagnostic efficacy of BPE and MPE and could help compensate for the deficiency of cytology.

Conclusions

Our results indicated that SHOX2 and RASSF1A methylation panel detection could accurately classify BPE and MPE diseases and showed better diagnostic performance than traditional serum parameters. The SHOX2 and RASSF1A methylation detection of PE-cfDNA could be a potentially effective complementary tool for cytology in the process of differential diagnosis. In summary, PE-cfDNA could be used as a promising non-invasive analyte for the auxiliary diagnosis of MPE.

Therapeutic Monitoring of Orally Administered, Small-Molecule Anticancer Medications with Tumor-Specific Cellular Protein Targets in Peripheral Fluid Spaces-A Review

Orally administered, small-molecule anticancer drugs with tumor-specific cellular protein targets (OACD) have revolutionized oncological pharmacotherapy. Nevertheless, the differences in exposure to these drugs in the systemic circulation and extravascular fluid compartments have led to several cases of therapeutic failure, in addition to posing unknown risks of toxicity. The therapeutic drug monitoring (TDM) of OACDs in therapeutically relevant peripheral fluid compartments is therefore essential. In this work, the available knowledge regarding exposure to OACD concentrations in these fluid spaces is summarized. A review of the literature was conducted by searching Embase, PubMed, and Web of Science for clinical research articles and case reports published between 10 May 2001 and 31 August 2022. Results show that, to date, penetration into cerebrospinal fluid has been studied especially intensively, in addition to breast milk, leukocytes, peripheral blood mononuclear cells, peritoneal fluid, pleural fluid, saliva and semen. The typical clinical indications of peripheral fluid TDM of OACDs were (1) primary malignancy, (2) secondary malignancy, (3) mental disorder, and (4) the assessment of toxicity. Liquid chromatography-tandem mass spectrometry was most commonly applied for analysis. The TDM of OACDs in therapeutically relevant peripheral fluid spaces is often indispensable for efficient and safe treatments.

Malignant Pleural Effusion in Pediatrics: A Rare Presentation

Pleural effusion is the most common presentation of pleural diseases. It is relatively common in children with two predominant types: exudative and transudative effusions. In children, exudative types are the most common with bacterial infection being the most prevalent cause. In some cases, effusion could be difficult to confirm. We describe two patients with a similar age group who presented with respiratory distress in the form of fever, cough, and shortness of breath. They were managed clinically and radiologically as cases of parapneumonic effusion. Both were started on antibiotics with no improvement. After reviewing the cases, it was discovered that some crucial aspects of the history and physical examination that were essential to reach the correct diagnosis had not been taken into consideration. Parapneumonic effusion should be taken with caution, meticulous history and examination are warranted, and lymphocytic-predominant effusion is very alarming for potential malignancy in the absence of tuberculosis infection. If the antibiotic medication yields no significant improvement, earlier referral should be considered.

Development and validation of a machine learning model for differential diagnosis of malignant pleural effusion using routine laboratory data

BACKGROUND

The differential diagnosis of malignant pleural effusion (MPE) and benign pleural effusion (BPE) presents a clinical challenge. In recent years, the use of artificial intelligence (AI) machine learning models for disease diagnosis has increased.

OBJECTIVE

This study aimed to develop and validate a diagnostic model for early differentiation between MPE and BPE based on routine laboratory data.

DESIGN

This was a retrospective observational cohort study.

METHODS

A total of 2352 newly diagnosed patients with pleural effusion (PE), between January 2008 and March 2021, were eventually enrolled. Among them, 1435, 466, and 451 participants were randomly assigned to the training, validation, and testing cohorts in a ratio of 3:1:1. Clinical parameters, including age, sex, and laboratory parameters of PE patients, were abstracted for analysis. Based on 81 candidate laboratory variables, five machine learning models, namely extreme gradient boosting (XGBoost) model, logistic regression (LR) model, random forest (RF) model, support vector machine (SVM) model, and multilayer perceptron (MLP) model were developed. Their respective diagnostic performances for MPE were evaluated by receiver operating characteristic (ROC) curves.

RESULTS

Among the five models, the XGBoost model exhibited the best diagnostic performance for MPE (area under the curve (AUC): 0.903, 0.918, and 0.886 in the training, validation, and testing cohorts, respectively). Additionally, the XGBoost model outperformed carcinoembryonic antigen (CEA) levels in pleural fluid (PF), serum, and the PF/serum ratio (AUC: 0.726, 0.699, and 0.692 in the training cohort; 0.763, 0.695, and 0.731 in the validation cohort; and 0.722, 0.729, and 0.693 in the testing cohort, respectively). Furthermore, compared with CEA, the XGBoost model demonstrated greater diagnostic power and sensitivity in diagnosing lung cancer-induced MPE.

CONCLUSION

The development of a machine learning model utilizing routine laboratory biomarkers significantly enhances the diagnostic capability for distinguishing between MPE and BPE. The XGBoost model emerges as a valuable tool for the diagnosis of MPE.

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.

High-Throughput Separation and Enrichment of Rare Malignant Tumor Cells from Large-Volume Effusions by Inertial Microfluidics

Detection of malignant tumor cells (MTCs) in pleural effusions is essential for determining the malignancy. However, the sensitivity of MTC detection is significantly decreased due to the existence of a massive number of background blood cells in large-volume samples. Herein, we provide a method for on-chip separation and enrichment of MTCs from malignant pleural effusions (MPEs) by integrating an inertial microfluidic sorter with an inertial microfluidic concentrator. The designed sorter and concentrator are capable of focusing cells toward the specified equilibrium positions by inducing intrinsic hydrodynamic forces, enabling the size-based sorting of cells and the removal of cell-free fluids for cell enrichment. A 99.9% removal of background cells and a nearly 1400-fold ultrahigh enrichment of MTCs from large-volume MPEs can be achieved by this method. The concentrated high-purity MTC solution can be used directly for cytological examination by immunofluorescence staining, enhancing the accurate identification of MPEs. The proposed method can also be employed for the detection and count of rare cells in various clinical samples.

A Novel Clinical Prognostic Model for Breast Cancer Patients with Malignant Pleural Effusion: Avoiding Chemotherapy in Low-Risk Groups?

Purpose

Malignant pleural effusion (MPE) is a severe complication in patients with advanced cancer that is associated with a poor prognosis. Breast cancer is the second leading cause of MPE after lung cancer. We therefore aim to describe clinical characteristics of the patients with MPE combined with breast cancer and construct a machine learning-based model for predicting the prognosis of such patients.

Methods

This study is a retrospective and observational study. Least absolute shrinkage and selection operator (LASSO) and univariate Cox regression analyses were applied to identify eight key clinical variables, and a nomogram model was established. Model performance was evaluated by receiver operating characteristic (ROC) curve, calibration curve, and decision curve analyses.

Results

196 patients with both MPE and breast cancer (143 in the training group and 53 in the ex-ternal validation group) were analyzed in this study. The median overall survival in two cohorts was 16.20 months and 11.37 months. Based on the ROC curves for 3-, 6-, and 12-month survival, the areas under the curves were 0.824, 0.824, and 0.818 in the training set and 0.777, 0.790, and 0.715 in the validation set, respectively. In the follow-up analysis, both systemic and intrapleural chemotherapy significantly increased survival in the high-risk group compared to the low-risk group.

Conclusion

Collectively, MPE confers a poor prognosis in breast cancer patients. We have developed a first-ever survival prediction model for breast cancer patients with newly diagnosed MPE and validated the model using an independent cohort.

Malignant pleural effusion diagnosis and therapy

Malignant pleural effusion (MPE) is a serious complication of advanced tumor, with relatively high morbidity and mortality rates, and can severely affect the quality of life and survival of patients. The mechanisms of MPE development are not well defined, but much research has been conducted to gain a deeper understanding of this process. In recent decades, although great progress has been made in the management of MPE, the diagnosis and treatment of MPE are still major challenges for clinicians. In this article, we provide a review of the research advances in the mechanisms of MPE development, diagnosis and treatment approaches. We aim to offer clinicians an overview of the latest evidence on the management of MPE, which should be individualized to provide comprehensive interventions for patients in accordance with their wishes, health status, prognosis and other factors.

Effect of chemotherapy, immunotherapy, and targeted therapies on removal of indwelling pleural catheters in non-small cell lung cancer patients with malignant pleural effusions

BACKGROUND

Indwelling pleural catheters (IPCs) are a mainstay therapy for malignant pleural effusions (MPEs). Many patients treated with IPCs achieve pleurodesis. We aimed to identify the effect of systemic therapies for non-small cell lung cancer (NSCLC) on IPC removal in patients with associated MPEs.

METHODS

We completed a retrospective cohort study of adult IPC recipients with metastatic NSCLC at the pleural effusion clinic at the Royal Alexandra Hospital from 2009 to 2020. We used logistic regression to assess the rates of IPC removal and Cox regression to assess the time to IPC removal.

RESULTS

232 patients met inclusion criteria with 248 IPCs reviewed. The overall pleurodesis rate was 42.7% with a median time to pleurodesis of 68 (IQR 38-140) days. In univariate analysis, chemotherapy (OR 1.86, CI 0.99-3.49) and epidermal growth factor receptor (EGFR) targeted therapy (OR 3.81, CI 1.86-7.79) were associated with higher rates of pleurodesis. In multivariate analysis, increased rates of pleurodesis were associated with an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of ≤2 (OR 4.82, CI 2.24-10.37) and EGFR targeted therapy (OR 3.87, CI 1.80-8.32). Earlier IPC removal was associated with EGFR targeted therapy in both univariate (HR 1.84, CI 1.20-2.83) and multivariate analysis (HR 1.86, CI 1.19-2.92).

CONCLUSIONS

Treatment with EGFR targeted therapy is associated with increased rates and earlier removal of IPC in patients with NSCLC in our cohort. Further large cohort studies are required to determine if this relationship persists.

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.

Soluble HLA peptidome: A new resource for cancer biomarkers

Using circulating molecular biomarkers to screen for cancer and other debilitating disorders in a high-throughput and low-cost fashion is becoming increasingly attractive in medicine. One major limitation of investigating protein biomarkers in body fluids is that only one-fourth of the entire proteome can be routinely detected in these fluids. In contrast, Human Leukocyte Antigen (HLA) presents peptides from the entire proteome on the cell surface. While peptide-HLA complexes are predominantly membrane-bound, a fraction of HLA molecules is released into body fluids which is referred to as soluble HLAs (sHLAs). As such peptides bound by sHLA molecules represent the entire proteome of their cells/tissues of origin and more importantly, recent advances in mass spectrometry-based technologies have allowed for accurate determination of these peptides. In this perspective, we discuss the current understanding of sHLA-peptide complexes in the context of cancer, and their potential as a novel, relatively untapped repertoire for cancer biomarkers. We also review the currently available tools to detect and quantify these circulating biomarkers, and we discuss the challenges and future perspectives of implementing sHLA biomarkers in a clinical setting.

Transcriptomics indicate nuclear division and cell adhesion not recapitulated in MCF7 and MCF10A compared to luminal A breast tumours

Breast cancer (BC) cell lines are useful experimental models to understand cancer biology. Yet, their relevance to modelling cancer remains unclear. To better understand the tumour-modelling efficacy of cell lines, we performed RNA-seq analyses on a combined dataset of 2D and 3D cultures of tumourigenic MCF7 and non-tumourigenic MCF10A. To our knowledge, this was the first RNA-seq dataset comprising of 2D and 3D cultures of MCF7 and MCF10A within the same experiment, which facilitates the elucidation of differences between MCF7 and MCF10A across culture types. We compared the genes and gene sets distinguishing MCF7 from MCF10A against separate RNA-seq analyses of clinical luminal A (LumA) and normal samples from the TCGA-BRCA dataset. Among the 1031 cancer-related genes distinguishing LumA from normal samples, only 5.1% and 15.7% of these genes also distinguished MCF7 from MCF10A in 2D and 3D cultures respectively, suggesting that different genes drive cancer-related differences in cell lines compared to clinical BC. Unlike LumA tumours which showed increased nuclear division-related gene expression compared to normal tissue, nuclear division-related gene expression in MCF7 was similar to MCF10A. Moreover, although LumA tumours had similar cell adhesion-related gene expression compared to normal tissues, MCF7 showed reduced cell adhesion-related gene expression compared to MCF10A. These findings suggest that MCF7 and MCF10A cell lines were limited in their ability to model cancer-related processes in clinical LumA tumours.

Transthoracic sonographic scores in evaluating the success of different scelerosing modalities in patients with malignant pleural effusion

Background

Malignant pleural effusions (MPE) mostly arises from metastases to the pleura from other sites. Management of malignant effusions aims to palliate dyspnea and prevent the reaccumulation of pleural fluid to improve patients’ quality of life. Pleurodesis is the most common palliative treatment for patients with refractory MPE. This study was carried out to evaluate the performance of transthoracic sonographic (TUS) scores (pleural sliding and pleural adherence score) in predicting the success of pleurodesis by different modalities in patients with malignant pleural effusion. One hundred malignant pleural effusion patients were enrolled to an interventional clinical trial from September 2019 to April 2021 for palliative management of dyspnea. Pleurodesis for palliative treatment of dyspnea was done either spontaneously by the intercostal chest tube or by a sclerosing agent such as tetracycline solution or tetracycline poudrage or iodopovidine. Patients were randomly allocated to one of these four groups where each group included 25 patients. Transthoracic ultrasound was performed at baseline, and 1 month after pleurodesis and the lung sliding score and pleural adherence score were evaluated.

Results

Majority of patients (78%) had high baseline lung sliding score (7-8). Post pleurodesis only 11.4% had high scores (p<0.001), also the mean lung sliding score decreased significantly in comparison to the baseline values (p˂ 0.001) in the spontaneous, tetracycline solution, tetracycline poudrage, and iodopovidine groups (7.04 ± 1.02 vs. 4.85 ± 1.60, 7.28± 0.98 vs. 4.48± 1.75, 7.20±0.96 vs. 4.44 ± 1.45, 7.04±0.93 vs. 3.35±1.81, respectively). Iodopovidine pleurodesis group in comparison to the other modalities showed the highest pleural adherence score (12.64 ± 2.98) and absent lung sliding in 72.7% of cases and 70 % success rate. Pleural adherence score at cut off ≥ 12 showed 92.75% sensitivity, 89.47% specificity, 92.1 accuracy, and 0.911 area under the curve (AUC) for predicting successful pleurodesis.

Conclusion

TUS scores is a feasible, bedside, and accurate method to detect the outcome of pleurodesis. Iodopovidone was more effective than tetracycline solution, tetracycline poudrage, and spontaneous pleurodesis.

Trial registration

ClinicalTrials.gov. NCT04074902. Registered on 29 August 2019

Diagnosis of malignant pleural disease: Ultrasound as "a detective probe"

BACKGROUND

Malignant pleural mesothelioma (MPM) is an invasive, aggressive pleural tumor with a predominantly local spread. The objective of this study was to assess thoracic ultrasound (TUS) as an imaging modality with high sensitivity for the identification of malignant pleural involvement and in order to guide pleural biopsies.

METHODS

In this retrospective single-center study between January 2018 and June 2022, 51 consecutive patients with impassable circumferential pleural thickening underwent TUS at the Thoracic Surgery Unit of the Vanvitelli University of Naples. Pleural biopsies were performed, and then large and multiple samples were sent to the pathological anatomy for histological examination.

RESULTS

In all patients who underwent ultrasound examination, we chose the optimal point of entry to perform pleural biopsies and selected the areas of greater thickening without pleural effusion. No patient had any complications. No drainage tubes were placed after the pleural biopsies and no pneumothorax was present during the following days of hospitalization. The patients were discharged on the second postoperative day.

CONCLUSION

With TUS the precise pleural thickening localization, local infiltration, mass extent, its nature (solid, cystic or complex) and ultrasound features can be easily defined. Furthermore, ultrasound is more economical than computed tomography and avoids the risks associated with radiation. Thoracic ultrasound is an important component of the diagnostic procedure in detecting a safe entry site for biopsies of MPMs.

A PD-L1-targeting chimeric switch receptor enhances efficacy of CAR-T cell for pleural and peritoneal metastasis

Pleural and peritoneal metastasis accompanied by malignant pleural effusion (MPE) or malignant ascites (MA) is frequent in patients with advanced solid tumors that originate from the lung, breast, gastrointestinal tract and ovary. Regional delivery of CAR-T cells represents a new strategy to control tumor dissemination in serous cavities. However, malignant effusions constitute an immune-suppressive environment that potentially induces CAR-T cell dysfunction. Here, we demonstrated that the anti-tumor cytotoxicity of conventional 2nd-generation CAR-T cells was significantly inhibited by both the cellular and non-cellular components of MPE/MA, which was primarily attributed to impaired CAR-T cell proliferation and cytokine production in MPE/MA environment. Interestingly, we found that PD-L1 was widely expressed on freshly-isolated MPE/MA cells. Based on this feature, a novel PD-L1-targeting chimeric switch receptor (PD-L1.BB CSR) was designed, which can bind to PD-L1, switching the inhibitory signal into an additional 4-1BB signal. When co-expressed with a 2nd-generation CAR, PD-L1.BB CSR-modified CAR-T cells displayed superior fitness and enhanced functions in both culture medium and MPE/MA environment, causing rapid and durable eradication of pleural and peritoneal metastatic tumors in xenograft models. Further investigations revealed elevated expressions of T-cell activation, proliferation, and cytotoxicity-related genes, and we confirmed that PD-L1 scFv and 4-1BB intracellular domain, the two important components of PD-L1.BB CSR, were both necessary for the functional improvements of CAR-T cells. Overall, our study shed light on the clinical application of PD-L1.BB CSR-modified dual-targeting CAR-T cells. Based on this study, a phase I clinical trial was initiated in patients with pleural or peritoneal metastasis (NCT04684459).

Implementation of evidence on management of pleural diseases: insights from a territory-wide survey of clinicians in Hong Kong

BACKGROUND

Major advances in management of common pleural diseases have taken place in the past decade. However, pleural diseases are often managed by physicians of diverse training background and research on implementation of new knowledge is scanty. We aim to evaluate the practice pattern in pleural medicine among physicians in Hong Kong, for identification of possible gaps for clinical service improvement.

METHODS

The Hong Kong Thoracic Society undertook a cross-sectional questionnaire survey in 2019, targeting clinicians of various subspecialties in internal medicine and levels of experience (basic and higher trainees, specialists) from twelve regional hospitals of diverse service scopes throughout Hong Kong. Respondents were selected by non-probability quota sampling. The questionnaire tool consisted of 46 questions covering diagnostic and therapeutic aspects of common pleural diseases. The responses were anonymous, and analysed independently using SPSS statistics software.

RESULTS

The survey collected 129 responses, 47(36%) were from clinicians specialized in respiratory medicine. Majority of the respondents (98%) managed pleural diseases, including performing pleural procedures in their practice. Fifty-five percent of all the respondents had not received any formal training in transthoracic ultrasonography. A significant proportion of clinicians were unaware of pleuroscopy for investigation of exudative pleural effusion, indwelling pleural catheter for recurrent malignant pleural effusion, and combined intra-pleural Alteplase plus DNase for treatment of pleural infection (30%, 15% and 70% of non-respiratory clinicians respectively). Significant heterogeneity was found in the management of pleural infection, malignant pleural effusion and pneumothorax among respiratory versus non-respiratory clinicians. Contributing factors to the observed heterogeneity included lack of awareness or training, limited accessibility of drugs, devices, or dedicated service support.

CONCLUSION

Significant heterogeneity in management of pleural diseases was observed among medical clinicians in Hong Kong. Continuous medical education and training provision for both specialists and non-specialists has to be strengthened to enhance the implementation of advances, improve quality and equity of healthcare provision in pleural medicine.

Malignant Pleural Effusion: Presentation, Diagnosis, and Management

Malignant pleural effusions are common in patients with cancer. Most malignant pleural effusions are secondary to metastases to the pleura, most often from lung or breast cancer. The presence of malignant effusion indicates advanced disease and poor survival; in lung cancer, the presence of malignant effusion upstages the cancer to stage 4. Usually presenting as a large, unilateral exudative effusion, most patients with malignant pleural effusion experience dyspnea. Prior to intervention, diagnosis of malignant pleural effusion and exclusion of infection should be made. Thoracic imaging is typically performed, with computed tomography considered by many to be the gold standard. Thoracic ultrasound is also useful, particularly if diaphragmatic or pleural thickening and nodularity can be identified. Cytology should then be obtained; this is typically done via pleural fluid aspiration or pleural biopsy. Treatment focuses on palliation and relief of symptoms. Numerous interventions are available, ranging from drainage with thoracentesis or indwelling pleural catheter to more definitive, invasive options such as pleurodesis. There is no clear best approach, and a patient-centered approach should be taken.

Influence of Malignant Pleural Fluid from Lung Adenocarcinoma Patients on Neutrophil Response

Simple Summary

This study provides novel information about the role of neutrophils in malignant pleural effusion (MPE) and hallmarks their clinical relevance. Since these cells have emerged as important regulators of cancer, we characterized their phenotype and functions in MPE microenvironment. We found that neutrophil-derived products (degranulation molecules and neutrophil extracellular traps (NETs)) were increased in MPE. In addition, NETs were associated with a worse outcome in lung adenocarcinoma patients with MPE.

Abstract

Malignant pleural effusion (MPE) is a common severe complication of advanced lung adenocarcinoma (LAC). Neutrophils, an essential component of tumor infiltrates, contribute to tumor progression and their counts in MPE have been associated with worse outcome in LAC. This study aimed to evaluate phenotypical and functional changes of neutrophils induced by MPE to determine the influence of MPE immunomodulatory factors in neutrophil response and to find a possible association between neutrophil functions and clinical outcomes. Pleural fluid samples were collected from 47 LAC and 25 heart failure (HF) patients. We measured neutrophil degranulation products by ELISA, oxidative burst capacity and apoptosis by flow cytometry, and NETosis by fluorescence. The concentration of degranulation products was higher in MPE-LAC than in PE-HF. Functionally, neutrophils cultured with MPE-LAC had enhanced survival and neutrophil extracellular trap (NET) formation but had reduced oxidative burst capacity. In MPE, NETosis was positively associated with MMP-9, P-selectin, and sPD-L1 and clinically related to a worse outcome. This is the first study associating NETs with a worse outcome in MPE. Neutrophils likely contribute to tumor progression through the release of NETs, suggesting that they are a potential therapeutic target in LAC.

Deconvolution of malignant pleural effusions immune landscape unravels a novel macrophage signature associated with worse clinical outcome in lung adenocarcinoma patients

Background

Immune checkpoint inhibitors are still unable to provide clinical benefit to the large majority of non-small cell lung cancer (NSCLC) patients. A deeper characterization of the tumor immune microenvironment (TIME) is expected to shed light on the mechanisms of cancer immune evasion and resistance to immunotherapy. Here, we exploited malignant pleural effusions (MPEs) from lung adenocarcinoma (LUAD) patients as a model system to decipher TIME in metastatic NSCLC.

Methods

Mononuclear cells from MPEs (PEMC) and peripheral blood (PBMC), cell free pleural fluid and/or plasma were collected from a total of 24 LUAD patients and 12 healthy donors. Bulk-RNA sequencing was performed on total RNA extracted from PEMC and matched PBMC. The DEseq2 Bioconductor package was used to perform differential expression analysis and CIBERSORTx for the regression-based immune deconvolution of bulk gene expression data. Cytokinome analysis of cell-free pleural fluid and plasma samples was performed using a 48-Plex Assay panel. THP-1 monocytic cells were used to assess macrophage polarization. Survival analyses on NSCLC patients were performed using KM Plotter (LUAD, N=672; lung squamous cell carcinoma, N=271).

Results

Transcriptomic analysis of immune cells and cytokinome analysis of soluble factors in the pleural fluid depicted MPEs as a metastatic niche in which all the components required for an effective antitumor response are present, but conscripted in a wound-healing, proinflammatory and tumor-supportive mode. The bioinformatic deconvolution analysis revealed an immune landscape dominated by myeloid subsets with the prevalence of monocytes, protumoral macrophages and activated mast cells. Focusing on macrophages we identified an MPEs-distinctive signature associated with worse clinical outcome in LUAD patients.

Conclusions

Our study reports for the first time a wide characterization of MPEs LUAD microenvironment, highlighting the importance of specific components of the myeloid compartment and opens new perspectives for the rational design of new therapies for metastatic NSCLC.

Intrapleural Perfusion With Staphylococcal Enterotoxin C for Malignant Pleural Effusion: A Clustered Systematic Review and Meta-Analysis

Introduction

The staphylococcal enterotoxin C (SEC), a commercially available bio-product from Staphylococcus aureus (S. aureus), has been widely used to control MPE.

Objectives

We designed and performed a new systematic review (SR) and meta-analysis to clarify the perfusion protocols with SEC, determine their clinical effectiveness and safety, and reveal the indication and optimum usage for achieving the desired responses.

Methodology

All randomized controlled trials (RCTs) about SEC for MPE were collected from electronic databases (from inception until July 2021), and clustered into multiple logical topics. After evaluating their methodological quality, we pooled the data from each topic using the meta-analysis or descriptive analysis, and summarized the evidence quality using the grading of recommendation assessment, development, and evaluation (GRADE) approach.

Results

All 114 studies were clustered into SEC perfusion alone or plus chemical agents. The SEC alone showed a better complete response (CR), a lower pleurodesis failure, and adverse drug reactions (ADRs), and a higher fever than cisplatin (DDP) alone. The SEC and chemical agents developed 10 perfusion protocols. Among them, only SEC and DDP perfusion showed a better CR, a lower failure, disease progression and ADRs, and a higher fever than DDP alone. The SEC (100–200 ng per time, one time a week for one to four times) with DDP (30–40 mg, or 50–60 mg each time) significantly improved clinical responses for patients with moderate to large volume, Karnofsky performance status (KPS) scores ≥40, ≥50, or ≥60, and anticipated survival time (AST) ≥2 or 3 months. Most results were moderate to low quality.

Conclusion

Current pieces of evidence indicate that super-antigen SEC is a pleurodesis agent, which provides an attractive alternative to existing palliative modalities for patients with MPE. Among 10 protocols, the SEC and DDP perfusion is a most commonly used, which shows a significant improvement in clinical responses with low ADRs. These findings also provide a possible indication and optimal usage for SEC and DDP perfusion.

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.