Malignant pleural effusion: medical approaches for diagnosis and management

Diagnostic value of CEACAM6 and HE4 in pleural fluid for malignant pleural effusion

OBJECTIVE

This study aimed to assess the diagnostic performance of carcinoembryonic antigen-related adhesion molecule 6 (CEACAM6) and human epididymis protein 4 (HE4) in pleural fluid for the detection of malignant pleural effusion (MPE).

MATERIALS AND METHODS

In this prospective study, pleural levels of CEACAM6 and HE4 were measured in two independent cohorts. The test cohort included 182 patients with exudative pleural effusions (123 malignant and 59 benign), and the validation cohort comprised 117 patients with exudative pleural effusions (65 malignant and 52 benign). Receiver operating characteristic (ROC) curves were used to assess the diagnostic performance of CEACAM6 and HE4 for MPE.

RESULTS

Both CEACAM6 and HE4 levels were significantly elevated in MPE compared to benign pleural effusion (BPE) in both cohorts (p < .001). In the test cohort, CEACAM6 and HE4 demonstrated areas under the curve (AUC) values of 0.862 and 0.826, respectively. The combination of CEACAM6 and HE4 yielded a higher AUC of 0.938 compared to either marker alone. In the validation cohort, both CEACAM6 (AUC = 0.811) and HE4 (AUC = 0.721), along with their combination (AUC = 0.834), exhibited strong diagnostic performance for MPE. Notably, in cytology-negative cases, the combination of CEACAM6 and HE4 also demonstrated a favourable diagnostic efficacy, with an AUC of 0.800. The addition of CEA to the CEACAM6/HE4 combination further improved the AUC to 0.819 (p = .04).

CONCLUSIONS

Pleural CEACAM6 and HE4 are promising biomarkers for distinguishing MPE from BPE. Their combination improves diagnostic accuracy, offering a valuable tool for MPE diagnosis, especially in challenging cases with cytology-negative pleural effusion.

The Diagnosis of Malignant Pleural Effusion Using Tumor-Marker Combinations: A Cost-Effectiveness Analysis Based on a Stacking Model

PURPOSE

By incorporating the cost of multiple tumor-marker tests, this work aims to comprehensively evaluate the financial burden of patients and the accuracy of machine learning models in diagnosing malignant pleural effusion (MPE) using tumor-marker combinations.

METHODS

Carcinoembryonic antigen (CEA), carbohydrate antigen (CA)19-9, CA125, and CA15-3 were collected from pleural effusion (PE) and peripheral blood (PB) of 319 patients with pleural effusion. A stacked ensemble (stacking) model based on five machine learning models was utilized to evaluate the diagnostic accuracy of tumor markers. We evaluated the discriminatory accuracy of various tumor-marker combinations using the area under the curve (AUC), sensitivity, and specificity. To evaluate the cost-effectiveness of different tumor-marker combinations, a comprehensive score (C-score) with a tuning parameter w was proposed.

RESULTS

In most scenarios, the stacking model outperformed the five individual machine learning models in terms of AUC. Among the eight tumor markers, the CEA in PE (PE.CEA) showed the best AUC of 0.902. Among all tumor-marker combinations, the PE.CA19-9 + PE.CA15-3 + PE.CEA + PB.CEA combination (C9 combination) achieved the highest AUC of 0.946. When w puts more weight on the cost, the highest C-score was achieved with the single PE.CEA marker. As w puts over 0.8 weight on AUC, the C-score favored diagnostic models with more expensive tumor-marker combinations. Specifically, when w was set to 0.99, the C9 combination achieved the best C-score.

CONCLUSION

The stacking diagnostic model using PE.CEA is a relatively accurate and affordable choice in diagnosing MPE for patients without medical insurance or in a low economic level. The stacking model using the combination PE.CA19-9 + PE.CA15-3 + PE.CEA + PB.CEA is the most accurate diagnostic model and the best choice for patients without an economic burden. From a cost-effectiveness perspective, the stacking diagnostic model with PE.CA19-9 + PE.CA15-3 + PE.CEA combination is particularly recommended, as it gains the best trade-off between the low cost and high effectiveness.

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.

Application of the International System for Reporting Serous Fluid Cytopathology to pericardial fluid: Root cause analysis of indeterminate diagnoses, cytohistological correlation, and assessment of malignancy risk

BACKGROUND

This study investigates the utility of the International System for Reporting Serous Fluid Cytopathology (ISRSFC) in the categorization of pericardial fluid and assesses the diagnostic performance and risk of malignancy (ROM) for each of the diagnostic categories.

METHODS

All pericardial fluid cases at the Yale School of Medicine between January 1, 2017, and December 31, 2020, were reviewed. The diagnoses were reclassified into five categories according to the ISRSFC: nondiagnostic (ND), negative for malignancy (NFM), atypia of uncertain significance (AUS), suspicious for malignancy (SFM), and malignant (MAL). ROM and performance parameters of each category were calculated.

RESULTS

After reclassification, the distribution of 465 pericardial fluid cases in each category was as follows: ND, 19 (4.1%); NFM, 332 (71.4%); AUS, 21 (4.5%); SFM, 11 (2.4%); and MAL, 82 (17.6%). Confirmatory follow-ups were available for 16 ND (66.7%), 299 NFM (90%), 15 AUS (71%), 5 SFM (45.5%), and 30 MAL cases (36.6%). The ROM was 0% for ND, 1.3% for NFM (4 of 332), 20% for AUS (3 of 15), and 100% for both SFM (5 of 5) and MAL (27 of 27). The diagnostic performance was as follows: sensitivity, 87% (27 of 31); specificity, 100% (292 of 292); positive predictive value (PPV), 100% (27 of 27); negative predictive value (NPV), 98.6% (292 of 296); and diagnostic accuracy, 98.8% (319 of 323).

CONCLUSIONS

The ISRSFC is a highly useful system for the reporting of pericardial fluid and risk assessment, given that it offers high sensitivity, specificity, PPV, NPV, and diagnostic accuracy. The application of this system may help to better categorize pericardial fluid and facilitate the standardization of cytopathology reporting.

Diagnosis of malignant pleural effusion with combinations of multiple tumor markers: A comparison study of five machine learning models

BACKGROUND

To evaluate the diagnostic value of combinations of tumor markers carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 125, CA153, and CA19-9 in identifying malignant pleural effusion (MPE) from non-malignant pleural effusion (non-MPE) using machine learning, and compare the performance of popular machine learning methods.

METHODS

A total of 319 samples were collected from patients with pleural effusion in Beijing and Wuhan, China, from January 2018 to June 2020. Five machine learning methods including Logistic regression, extreme gradient boosting (XGBoost), Bayesian additive regression tree, random forest, and support vector machine were applied to evaluate the diagnostic performance. Sensitivity, specificity, Youden's index, and the area under the receiver operating characteristic curve (AUC) were used to evaluate the performance of different diagnostic models.

RESULTS

For diagnostic models with a single tumor marker, the model using CEA, constructed by XGBoost, performed best (AUC = 0.895, sensitivity = 0.80), and the model with CA153, also by XGBoost, showed the largest specificity 0.98. Among all combinations of tumor markers, the combination of CEA and CA153 achieved the best performance (AUC = 0.921, sensitivity = 0.85) in identifying MPE under the diagnostic model constructed by XGBoost.

CONCLUSIONS

Diagnostic models for MPE with a combination of multiple tumor markers outperformed the models with a single tumor marker, particularly in sensitivity. Using machine learning methods, especially XGBoost, could comprehensively improve the diagnostic accuracy of MPE.

Lung Cancer: Spectral and Numerical Differentiation among Benign and Malignant Pleural Effusions Based on the Surface-Enhanced Raman Spectroscopy

We present here that the surface-enhanced Raman spectroscopy (SERS) technique in conjunction with the partial least squares analysis is as a potential tool for the differentiation of pleural effusion in the course of the cancerous disease and a tool for faster diagnosis of lung cancer. Pleural effusion occurs mainly in cancer patients due to the spread of the tumor, usually caused by lung cancer. Furthermore, it can also be initiated by non-neoplastic diseases, such as chronic inflammatory infection (the most common reason for histopathological examination of the exudate). The correlation between pleural effusion induced by tumor and non-cancerous diseases were found using surface-enhanced Raman spectroscopy combined with principal component regression (PCR) and partial least squares (PLS) multivariate analysis method. The PCR predicts 96% variance for the division of neoplastic and non-neoplastic samples in 13 principal components while PLS 95% in only 10 factors. Similarly, when analyzing the SERS data to differentiate the type of tumor (squamous cell vs. adenocarcinoma), PLS gives more satisfactory results. This is evidenced by the calculated values of the root mean square errors of calibration and prediction but also the coefficients of calibration determination and prediction (R2C = 0.9570 and R2C = 0.7968), which are more robust and rugged compared to those calculated for PCR. In addition, the relationship between cancerous and non-cancerous samples in the dependence on the gender of the studied patients is presented.

Intrapleural treatment in patients with non-small cell lung cancer with malignant pleural effusions in the real world

Background

The aim of the study was to assess the efficacy and side‐effects of intrapleural treatment in non‐small cell lung cancer (NSCLC) patients with malignant pleural effusions (MPEs).

Methods

The medical records of NSCLC patients with MPEs diagnosed in four Chinese hospitals from October 2014 to December 2019 were searched. The Kaplan–Meier method is used to calculate median overall survival (MOS) and subgroup analyses are done.

Results

A total of 285 patients were evaluated; 81.1% of patients received intrapleural treatment, and no patients received talc pleurodesis. MOS of the whole cohort was 21 months. Patients were divided into three groups: erythromycin group (EG; intrapleural treatment with drugs and erythromycin); intrathoracic treatment group (ITG; intrapleural treatment with drugs); control group (CG; no drug treatment in the pleural cavity). The MOS of patients in the EG, ITG and CG was 20, 22, and 19 months, respectively. Among patients who received only chemotherapy as systemic therapy, the MOS of intrathoracic administration group (IAG; i.e., EG and ITG) was longer than that of CG (12 vs. 6 months; p = 0.034), and the MOS of patients with a ratio of carcinoembryonic antigen in pleural effusion (PE‐CEA): CEA in blood (B‐CEA) ≤1 is worse than that of patients with a ratio >1 (4 vs. 12 months, p = 0.021) and that of CG (4 vs. 6 months, p = 0.442).

Conclusions

Intrapleural treatment can prolong the survival of NSCLC patients with MPE who do not receive targeted treatment or who only receive chemotherapy. The PE‐CEA: B‐CEA ratio can be used to predict the efficacy if intrapleural treatment is indicated.

Systemic Inflammatory Response to Different Sclerosing Agents as a Predictor of Pleurodesis Outcome

BACKGROUND/AIM

The objectives of this study were to evaluate systemic inflammation using different sclerosing agents and to estimate the prediction of systemic inflammation for the efficacy of pleurodesis.

PATIENTS AND METHODS

Ninety-six patients with recurrent and symptomatic malignant pleural effusion were enrolled in this retrospective study. We used serum C-reactive protein (CRP) levels, serum leukocyte counts and neutrophil-to-lymphocyte ratios (NLRs) as parameters of systemic inflammatory reactions. Evaluations of these parameters were performed before and 24 h after pleurodesis.

RESULTS

Pleurodesis was successful in 81 (84.4%) patients. The non-graded talc induced the highest changes in serum CRP levels, total white blood cell and neutrophil counts compared to other agents, while mitoxantrone induced the lowest. Graded talc and bleomycin induced the same levels of changes in serum CRP levels and serum leukocyte counts. The change in serum NLR was the same for all agent groups. Logistic regression confirmed that a change in serum CRP levels [odds ratio (OR)=0.92, p=0.002] and previous chemotherapy (OR=3.31, p=0.012) were independent predictors of pleurodesis efficacy.

CONCLUSION

Pleurodesis agents induced a systemic inflammatory response at different levels. The change in serum CRP levels could be useful for predicting the success of pleurodesis.

Clinical course of asymptomatic malignant pleural effusion in non-small cell lung cancer patients: A multicenter retrospective study

The British Thoracic Society guidelines recommend observation for patients with asymptomatic malignant pleural effusion (MPE). However, asymptomatic MPE can become symptomatic. This study examined the clinical course of asymptomatic MPE in patients with non-small cell lung cancer (NSCLC), including the incidence and timing of symptom development of asymptomatic MPE and the associated factors.Retrospective data of 4822 NSCLC patients between January 2012 and December 2017 were reviewed. Symptom development of asymptomatic MPE was defined as the development of symptoms requiring additional treatment, such as insertion of a chest tube, within 1 year in patients who lacked MPE symptoms at the time of diagnosis. Clinical information, pathological parameters, and radiological characteristics were reviewed. Patient data up to 1 year from the initial diagnosis were reviewed.Of 113 patients with asymptomatic MPE, 46 (41%) became symptomatic within 1 year despite appropriate anticancer treatment. The median time to symptom development was 4 months, and 38 patients (83%) developed symptoms within 6 months. Multivariate logistic regression showed that female sex (odds ratio [OR], 0.256; 95% confidence interval [CI], 0.101-0.649; P = .004) and the depth of pleural effusion on initial computed tomography (CT) (OR, 0.957; 95% CI, 0.932-0.982; P = .001) were independently associated with symptom development of asymptomatic MPE.A fraction of 41% of patients with asymptomatic MPE became symptomatic within 1 year. Female sex and larger MPE on initial CT were independently associated with symptom development of asymptomatic MPE.

Machine learning applied to near-infrared spectra for clinical pleural effusion classification

Lung cancer patients with malignant pleural effusions (MPE) have a particular poor prognosis. It is crucial to distinguish MPE from benign pleural effusion (BPE). The present study aims to develop a rapid, convenient and economical diagnostic method based on FTIR near-infrared spectroscopy (NIRS) combined with machine learning strategy for clinical pleural effusion classification. NIRS spectra were recorded for 47 MPE samples and 35 BPE samples. The sample data were randomly divided into train set (n = 62) and test set (n = 20). Partial least squares, random forest, support vector machine (SVM), and gradient boosting machine models were trained, and subsequent predictive performance were predicted on the test set. Besides the whole spectra used in modeling, selected features using SVM recursive feature elimination algorithm were also investigated in modeling. Among those models, NIRS combined with SVM showed the best predictive performance (accuracy: 1.0, kappa: 1.0, and AUC_ROC: 1.0). SVM with the top 50 feature wavenumbers also displayed a high predictive performance (accuracy: 0.95, kappa: 0.89, AUC_ROC: 0.99). Our study revealed that the combination of NIRS and machine learning is an innovative, rapid, and convenient method for clinical pleural effusion classification, and worth further evaluation.

Diagnostic value of human epididymis protein 4 in malignant pleural effusion in lung cancer

OBJECTIVE

This study aimed to assess the diagnostic value of human epididymis protein 4 (HE4) in the pleural effusion of lung cancer patients.

METHODS

HE4 protein in the pleural effusion of 60 lung cancer patients was measured by electrochemiluminescence, in parallel with those from 56 patients with benign lung disease, and the association with malignant pleural effusion was evaluated.

RESULTS

The level of HE4 in samples from lung cancer patients was significantly higher than the level for those with benign lung lesions (P= 0.001) and patients with lung adenocarcinoma showed significantly higher levels of HE4 than those with squamous cell carcinoma and small cell carcinoma (P= 0.002 and P= 0.034, respectively). Using an optimal threshold of 652.2 pmol/L, the HE4 level distinguished malignant lung cancer from benign lesions with a sensitivity of 78.3% and a specificity of 75.0%. Moreover, the HE4 level differentiated adenocarcinoma from benign lesions with a sensitivity of 75.9% and a specificity of 85.7% when a threshold of 744.05 pmol/L was used. However, there was no significant difference in the 2 year survival rates of lung cancer patients with high and low HE4 concentrations in pleural fluid (P= 0.882). In addition, there was no significant difference in HE4 levels between tuberculous and inflammatory pleural effusions (P= 0.309).

CONCLUSION

HE4 in the pleural fluid of lung cancer patients can be valuable in the diagnosis of malignant pleural effusion; however, it does not correlate with the prognosis of patients.

Multiplexed molecular profiling of lung cancer with malignant pleural effusion using next generation sequencing in Chinese patients

Lung cancer is the most common type of cancer and the leading cause of cancer-associated death worldwide. Malignant pleural effusion (MPE), which is observed in ~50% of advanced non-small cell lung cancer (NSCLC) cases, and most frequently in lung adenocarcinoma, is a common complication of stage III-IV NSCLC, and it can be used to predict a poor prognosis. In the present study, multiple oncogene mutations were detected, including 17 genes closely associated with initiation of advanced lung cancer, in 108 MPE samples using next generation sequencing (NGS). The NGS data of the present study had broader coverage, deeper sequencing depth and higher capture efficiency compared with NGS findings of previous studies on MPE. In the present study, using NGS, it was demonstrated that 93 patients (86%) harbored EGFR mutations and 62 patients possessed mutations in EGFR exons 18-21, which are targets of available treatment agents. EGFR L858R and exon 19 indel mutations were the most frequently observed alterations, with frequencies of 31 and 25%, respectively. In 1 patient, an EGFR amplification was identified and 6 patients possessed a T790M mutation. ALK + EML4 gene fusions were identified in 6 patients, a ROS1 + CD74 gene fusion was detected in 1 patient and 10 patients possessed a BIM (also known as BCL2L11) 2,903-bp intron deletion. In 4 patients, significant KRAS mutations (G12D, G12S, G13C and A146T) were observed, which are associated with resistance to afatinib, icotinib, erlotinib and gefitinib. There were 83 patients with ERBB2 mutations, but only two of these mutations were targets of available treatments. The results of the present study indicate that MPE is a reliable specimen for NGS based detection of somatic mutations.

Are we ready to develop a tiered scheme for the effusion cytology? A comprehensive review and analysis of the literature

BACKGROUND

Cytology is widely utilized in the initial evaluation of fluid accumulation in the body cavities. The aim of this study was to determine the accuracy of cytology in distinguishing between benign and malignant (MAL) effusions.

METHODS

A comprehensive and systematic review of the literature was conducted to evaluate the accuracy of serous effusion cytology (SEC) against tissue biopsy/resection histology, imaging, or clinical follow-up as the reference test. Risk of publication bias and level of heterogeneity in the included studies was assessed. Meta-regression was performed to assess the effect of various variables on the accuracy of SEC.

RESULTS

Eighty studies met the inclusion criteria for meta-analysis comprising of 34 941 samples; of which 52 (0.2%), 22 202 (72.7%), 194 (0.6%), 711 (2.3%), and 6507 (21.3%) could be reclassified as nondiagnostic (ND), negative for malignancy (NFM), atypical (atypia of uncertain significance-AUS), suspicious for malignancy (SFM), and malignant (MAL), respectively. On follow-up, the mean risk of malignancy for ND, NFM, AUS, SFM, MAL was 17.4%, 20.7%, 65.9%, 81.8%, and 98.9%, respectively. A total of 73 studies were included in estimating the diagnostic accuracy of SEC. The bivariate mixed-effect model estimated the SEC sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, and negative likelihood ratio as 73.1%, 99.9%, 7850.6%, 2112.2%, and 0.27%, respectively.

CONCLUSION

Serous effusion cytology shows high specificity and moderate sensitivity in the evaluation of serous effusions. A tiered classification scheme can improve the consistency of terminology for reporting SEC results, thus improving communication between the pathologists and clinical team, and quality of patient care.

Thymidine kinase 1 concentration in pleural effusion is a diagnostic marker and survival predictor for malignant pleural effusion

Objective

Thymidine kinase 1 (TK1) is a key enzyme in the pyrimidine salvage pathway. Increased TK1 concentration correlates with cell division. TK1 is an emerging biomarker in cancer diagnosis; however, its effectiveness in diagnosis and management for malignant pleural effusion (MPE) is unclear. We evaluated the diagnostic efficiency and prognostic value of pleural effusion TK1 (pTK1) concentration for MPE.

Methods

From 2013 to 2017, 210 pleural effusion samples were collected from 160 patients diagnosed with MPE and 50 patients diagnosed with benign pleural effusion (BPE). TK1 concentrations in pleural effusion were measured by chemiluminescence dot blot assays. The median follow‐up was 12 months. We constructed a receiver‐operating characteristic (ROC) curve to find the optimal cutoff value for MPE diagnosis. The hazard ratios were estimated using a multivariable Cox proportional hazard model. A nomogram was drawn to illustrate the prognostic characteristics of MPE.

Results

The TK1 concentration in pleural effusion was significantly higher in MPE than BPE (P < 0.001), and patients with MPE could be distinguished by an optimal cutoff value of 3.10 pmol/L with a sensitivity of 0.894 and a specificity of 0.800. The multivariate analysis suggested that pTK1 concentration was an independent predictor of survival in patients with MPE.

Conclusions

The diagnostic and prognostic prediction of MPE may be improved by measuring pTK1 concentration and utilizing a multivariate nomogram.

Epigenetically regulated PAX6 drives cancer cells toward a stem-like state via GLI-SOX2 signaling axis in lung adenocarcinoma

It remains unclear whether PAX6 acts as a crucial transcription factor for lung cancer stem cell (CSC) traits. We demonstrate that PAX6 acts as an oncogene responsible for induction of cancer stemness properties in lung adenocarcinoma (LUAD). Mechanistically, PAX6 promotes GLI transcription, resulting in SOX2 upregulation directly by the binding of GLI to the proximal promoter region of the SOX2 gene. The overexpressed SOX2 enhances the expression of key pluripotent factors (OCT4 and NANOG) and suppresses differentiation lineage factors (HOPX and NKX2-1), driving cancer cells toward a stem-like state. In contrast, in the differentiated non-CSCs, PAX6 is transcriptionally silenced by its promoter methylation. In human lung cancer tissues, the positive linear correlations of PAX6 expression with GLI and SOX2 expression and its negative correlations with HOPX and NKX2-1 expression were observed. Therapeutically, the blockade of the PAX6-GLI-SOX2 signaling axis elicits a long-lasting therapeutic efficacy by limiting CSC expansion following chemotherapy. Furthermore, a methylation panel including the PAX6 gene yielded a sensitivity of 79.1% and specificity of 83.3% for cancer detection using serum DNA from stage IA LUAD. Our findings provide a rationale for targeting the PAX6-GLI-SOX2 signaling axis with chemotherapy as an effective therapeutic strategy and support the clinical utility of PAX6 gene promoter methylation as a biomarker for early lung cancer detection.

Confocal Laser Endomicroscopy for Diagnosing Malignant Pleural Effusions

Background

Confocal laser endomicroscopy (CLE) enables “in vivo” microscopic tissue diagnosis based on tissue reflectance or tissue fluorescence upon application of fluorescence agents. The aim of the present study was to evaluate CLE as a new diagnostic approach for differentiation between malignant versus non-malignant pleural effusions.

Material/Methods

In 100 patients with pleural effusions, thoracentesis was performed. Cresyl violet and acriflavine were used as contrast agents for probe-based CLE of effusions. CLE video sequences were assessed by 4 independent investigators (2 experienced in this technique, 2 with only basic knowledge). In addition, all CLE samples were evaluated by an expert pathologist (p). Results were compared with conventional cytology of effusions and histology of cell blocks.

Results

CLE reliably permitted identification of malignant cells in pleural effusions. Sensitivity for detection of malignant effusions was 87% (p: 87%) and 81% (p: 72%) for acriflavine and cresyl violet, respectively. With regard to specificity, acriflavine and cresyl violet yielded a mean value of 99% (p: 100%) and 92% (p: 100%).

Conclusions

In this pilot study, CLE permitted simple and rapid detection of malignant pleural effusions. Larger prospective studies are warranted to corroborate our findings.

The role of VEGF in the diagnosis and treatment of malignant pleural effusion in patients with non‑small cell lung cancer (Review)

Malignant pleural effusion (MPE) is a severe medical condition, which can result in breathlessness, pain, cachexia and reduced physical activity. It can occur in almost all types of malignant tumors; however, lung cancer is the most common cause of MPE, accounting for ~1/3 of clinical cases. Although there are numerous therapeutic approaches currently available for the treatment of MPE, none are fully effective and the majority can only alleviate the symptoms of the patients. Vascular endothelial growth factor (VEGF) has now been recognized as one of the most important regulatory factors in tumor angiogenesis, which participates in the entire process of tumor growth through its function to stimulate tumor angiogenesis, activate host vascular endothelial cells and promote malignant proliferation. Novel drugs targeting VEGF, including endostar and bevacizumab, have been developed and approved for the treatment of various tumors. Data from recent clinical studies have demonstrated that drugs targeting VEGF are effective and safe for the clinical management of MPE. Therefore, VEGF‑targeting represents a promising novel strategy for the diagnosis and treatment of MPE. The present review summarized recent advances in the role of VEGF in the pathogenesis, diagnosis and clinical management of MPE in patients with non‑small cell lung cancer.

Outcomes of bevacizumab combined with chemotherapy in lung adenocarcinoma-induced malignant pleural effusion

BACKGROUND

VEGF is critical in the pathogenesis of malignant pleural effusion (MPE). To understand the clinical benefits of antiangiogenic agents, the efficacy of chemotherapy containing bevacizmab was investigated in patients with lung adenocarcinoma-induced MPE.

METHODS

The data of lung adenocarcinoma patients with MPE treated with bevacizumab plus chemotherapy on day 1, every three weeks, for ≤ 6 cycles was retrospectively collected. Patients who achieved a response or stable disease were administered bevacizumab as maintenance therapy until progression. The primary outcomes of the study were MPE response rate (RR), MPE control rate, and pleural progression-free survival (PPFS), while the secondary outcomes were PFS, overall survival (OS), changes to the lung volume and thoracic cage, and safety profiles.

RESULTS

A total of 21 cases were collected, and all were evaluable for response, including 15 chemotherapy-naïve patients and 6 who experienced relapse. The median cycle of treatments was 7 (1-42) and 5 (2-6) for bevacizumab and chemotherapy, respectively. The MPE RR reached 81.0%. The MPE control rate at 6, 12, 24, 48, and 96 weeks were 95.2%, 90.0%, 89.5%, 73.7%, and 43.8%, respectively. Median PPFS was significantly longer than PFS (22.2 vs. 7.8 months; P = 0.044), and median OS was 25.8 months. Nineteen (90.5%) patients experienced lung re-expansion after treatment. Only one (4.8%) patient suffered thoracic volume decrease during treatment and the follow-up period. No unexpected adverse events were observed.

CONCLUSIONS

Bevacizumab combined with chemotherapy demonstrated efficacious, persistence, and safety in controlling lung cancer-induced MPE, indicating a potential superior therapeutic option.

A Panel of Novel Detection and Prognostic Methylated DNA Markers in Primary Non-Small Cell Lung Cancer and Serum DNA

Purpose: To establish a novel panel of cancer-specific methylated genes for cancer detection and prognostic stratification of early-stage non-small cell lung cancer (NSCLC).Experimental Design: Identification of differentially methylated regions (DMR) was performed with bumphunter on "The Cancer Genome Atlas (TCGA)" dataset, and clinical utility was assessed using quantitative methylation-specific PCR assay in multiple sets of primary NSCLC and body fluids that included serum, pleural effusion, and ascites samples.Results: A methylation panel of 6 genes (CDO1, HOXA9, AJAP1, PTGDR, UNCX, and MARCH11) was selected from TCGA dataset. Promoter methylation of the gene panel was detected in 92.2% (83/90) of the training cohort with a specificity of 72.0% (18/25) and in 93.0% (40/43) of an independent cohort of stage IA primary NSCLC. In serum samples from the later 43 stage IA subjects and population-matched 42 control subjects, the gene panel yielded a sensitivity of 72.1% (31/41) and specificity of 71.4% (30/42). Similar diagnostic accuracy was observed in pleural effusion and ascites samples. A prognostic risk category based on the methylation status of CDO1, HOXA9, PTGDR, and AJAP1 refined the risk stratification for outcomes as an independent prognostic factor for an early-stage disease. Moreover, the paralog group for HOXA9, predominantly overexpressed in subjects with HOXA9 methylation, showed poor outcomes.Conclusions: Promoter methylation of a panel of 6 genes has potential for use as a biomarker for early cancer detection and to predict prognosis at the time of diagnosis. Clin Cancer Res; 23(22); 7141-52. ©2017 AACR.

Prognostic impact of a new score using neutrophil-to-lymphocyte ratios in the serum and malignant pleural effusion in lung cancer patients

Backgrounds

Various studies have reported that the neutrophil-to-lymphocyte ratio in the serum (sNLR) may serve as a cost-effective and useful prognostic factor in patients with various cancer types. However, no study has reported the prognostic impact of the NLR in malignant pleural effusion (MPE). To address this gap, we investigated the clinical impact of NLR as a prognostic factor in MPE (mNLR) and a new scoring system that use NLRs in the serum and MPE (smNLR score) in lung cancer patients.

Methods

We retrospectively reviewed all of the patients who were diagnosed with lung cancer and who presented with pleural effusion. To maintain the quality of the study, only patients with malignant cells in the pleural fluid or tissue were included. The patients were classified into three smNLR score groups, and clinical variables were investigated for their correlation with survival.

Results

In all, 158 patients were classified into three smNLR score groups as follows: 84 (53.2%) had a score of 0, 58 (36.7%) had a score of 1, and 16 (10.1%) had a score of 2. In a univariate analysis, high sNLR, mNLR, and increments of the smNLR score were associated with shorter overall survival (p < 0.001, p = 0.004, and p < 0.001, respectively); moreover, age, Eastern Cooperative Oncology Group performance status (ECOG PS), histology, M stage, hemoglobin level, albumin level, and calcium level were significant prognostic factors. A multivariable analysis confirmed that ECOG PS (p < 0.001), histology (p = 0.001), and smNLR score (p < 0.012) were independent predictors of overall survival.

Conclusions

The new smNLR score is a useful and cost-effective prognostic factor in lung cancer patients with MPE. Although further studies are required to generalize our results, this information will benefit clinicians and patients in determining the most appropriate therapy for patients with MPE.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3550-8) contains supplementary material, which is available to authorized users.

Transudative pleural effusion of malignant etiology: Rare but real

A 62-year-old female presented to the emergency room with one-month history of epigastric abdominal pain, nausea and vomiting. She endorsed progressive dyspnea over two weeks. CT of the abdomen demonstrated bilateral pleural effusions and pancreatic inflammation, so the working diagnosis was pancreatitis. A diagnostic thoracentesis was performed and the pleural fluid analysis was classified as transudate by Light's criteria. Given the atypical features in history and concern for malignancy, fluid was sent for cytological examination and immunohistochemistry which suggested a mucinous malignancy. EGD revealed poorly differentiated signet ring cell adenocarcinoma of stomach. Patient underwent placement of indwelling pleural catheters for symptomatic improvement and was discharged to hospice. The decision whether to routinely send transudative effusions for cytological evaluation remains controversial. This case demonstrates the importance of using clinical judgement to guide that decision.

Diagnostic Value of Neuron-Specific Enolase (NSE) and Cancer Antigen 15-3 (CA 15-3) in the Diagnosis of Pleural Effusions

Introduction: Pleural effusion diagnosis plays an important role in determining treatment strategies. The aim of this study was to determine the diagnostic capacity of tumor markers CA 15-3 and NSE solely or in combination in differentiating the nature of pleural fluid. Methods and Materials: In this cross-sectional study we evaluated 93 patients with pleural effusions (44 malignant and 49 benign). NSE and CA 15-3 serum and pleural levels were measured simultaneously using immunoenzyme assay kits. Diagnosis was established on the basis of cytological study. Results: Sensitivity and specificity of CA 15-3 serum and pleural level measurement were 70.4%, 49.0%, and 79.5% and 49.0%, respectively. Serum NSE levels had 75.0% sensitivity and 69.4% specificity while the respective pleural figures were 75.0% and 73.5%. The combination of NSE and CA 15-3 serum and pleural levels had the highest sensitivity (93.2%), although combined serum levels had the lowest sensitivity (47.7%). With an accuracy of 74.2%, pleural levels of NSE had the highest diagnostic potential. Conclusion: Measuring NSE and CA 15-3 tumor markers is a suitable approach to distinguish the nature of pleural effusions, with NSE pleural levels demonstrating the highest diagnostic accuracy.

Outcomes in Critically Ill Patients with Cancer-Related Complications

INTRODUCTION

Cancer patients are at risk for severe complications related to the underlying malignancy or its treatment and, therefore, usually require admission to intensive care units (ICU). Here, we evaluated the clinical characteristics and outcomes in this subgroup of patients.

MATERIALS AND METHODS

Secondary analysis of two prospective cohorts of cancer patients admitted to ICUs. We used multivariable logistic regression to identify variables associated with hospital mortality.

RESULTS

Out of 2,028 patients, 456 (23%) had cancer-related complications. Compared to those without cancer-related complications, they more frequently had worse performance status (PS) (57% vs 36% with PS≥2), active malignancy (95% vs 58%), need for vasopressors (45% vs 34%), mechanical ventilation (70% vs 51%) and dialysis (12% vs 8%) (P<0.001 for all analyses). ICU (47% vs. 27%) and hospital (63% vs. 38%) mortality rates were also higher in patients with cancer-related complications (P<0.001). Chemo/radiation therapy-induced toxicity (6%), venous thromboembolism (5%), respiratory failure (4%), gastrointestinal involvement (3%) and vena cava syndrome (VCS) (2%) were the most frequent cancer-related complications. In multivariable analysis, the presence of cancer-related complications per se was not associated with mortality [odds ratio (OR) = 1.25 (95% confidence interval, 0.94-1.66), P = 0.131]. However, among the individual cancer-related complications, VCS [OR = 3.79 (1.11-12.92), P = 0.033], gastrointestinal involvement [OR = 3.05 (1.57-5.91), P = <0.001] and respiratory failure [OR = 1.96(1.04-3.71), P = 0.038] were independently associated with in-hospital mortality.

CONCLUSIONS

The prognostic impact of cancer-related complications was variable. Although some complications were associated with worse outcomes, the presence of an acute cancer-related complication per se should not guide decisions to admit a patient to ICU.

Trends in Pleural Effusion Research

Background:

Research in pleural diseases has traditionally been neglected but is now growing.

Objectives:

This study aimed to analyze scientific research trends on pleural effusions over the last decades.

Method:

We conducted a bibliometric analysis of the Scopus database from its inception to March 2016, searching for original articles and reviews on “pleural effusion” (key word). Journal, year of publication, number of citations, authors and their affiliations, and the Hirsch (H)-index for some of these variables were recorded and analyzed.

Results:

A total of 15 982 documents were retrieved, of which half have been published in the last 18 years and a quarter during the last 8 years. Chest ranked first regarding the number of documents on pleural effusions (both absolute number and yearly rate) and their scientific relevance (H-index of 76). The United States had contributed the most to pleural research productivity (23%). American pulmonologists Dr Richard Light and Dr Steven Sahn exhibited the highest number of papers (206 and 156, respectively) and author H-indexes (44 and 38, respectively).

Conclusion:

There is growing research activity in the field of pleural effusions, which has gained relevance and visibility in clinical respiratory journals. The United States is the leader in quantity and quality of research productivity in pleural medicine.

Primary Malignant Neuroendocrine Tumour of Pleura: First Case Report

Metastatic tumours of pleura are the most common malignant tumours causing malignant pleural effusion. Lungs are the most common primary sites. Primary pleural tumours are rarely seen and diffuse malignant mesothelioma is the most common malignant tumour of pleura. Primary malignant neuroendocrine tumour of pleura is not reported in the literature. Here, we report a rare case of primary malignant neuroendocrine tumour of pleura in a fifty-two-year-old, nonsmoker female who presented with right-sided pleural effusion and ipsilateral, dull aching chest pain. Clinical presentations of inflammatory lesions like tuberculous pleuritis and benign and malignant neoplasms of pleura are indistinguishable; hence, fluid cytology, pleural biopsy, and immunohistochemistry are necessary for exact tissue diagnosis of the tumours, which is mandatory for correct treatment and prognostic assessment.

EGFR-L858R mutant enhances lung adenocarcinoma cell invasive ability and promotes malignant pleural effusion formation through activation of the CXCL12-CXCR4 pathway

Malignant pleural effusion (MPE) is a common clinical problem in non-small cell lung carcinoma (NSCLC) patients; however, the underlying mechanisms are still largely unknown. Recent studies indicate that the frequency of the L858R mutant form of the epidermal growth factor receptor (EGFR-L858R) is higher in lung adenocarcinoma with MPE than in surgically resected specimens, suggesting that lung adenocarcinoma cells harboring this mutation tend to invade the adjacent pleural cavity. The purpose of this study was to clarify the relationship between the EGFR-L858R mutation and cancer cell invasion ability and to investigate the molecular mechanisms involved in the formation of MPE. We found that expression of EGFR-L858R in lung cancer cells resulted in up-regulation of the CXCR4 in association with increased cancer cell invasive ability and MPE formation. Ectopic expression of EGFR-L858R in lung cancer cells acted through activation of ERK signaling pathways to induce the expression of CXCR4. We also indicated that Inhibition of CXCR4 with small interfering RNA, neutralizing antibody, or receptor antagonist significantly suppressed the EGFR-L858R–dependent cell invasion. These results suggest that targeting the production of CXCR4 and blocking the CXCL12-CXCR4 pathway might be effective strategies for treating NSCLCs harboring a specific type of EGFR mutation.

Silver nitrate versus tetracycline in pleurodesis for malignant pleural effusions; a prospective randomized trial

BACKGROUND

In this study, we aimed to investigate the effectiveness of silver nitrate (SN) versus tetracycline in pleurodesis among patients with malignant pleural effusion (MPE).

METHODS

In this prospective randomized clinical trial, patients with unilateral MPE candidate for pleurodesis were enrolled. The patients randomly allocated in two groups for receiving 20 mL 0.5% SN or 2.5 g tetracycline diluted in 30 cc normal saline and 0.1% lidocaine, through the chest tube. Patients were followed-up immediately (during 24 h) and 1-month after the procedure for evaluating recurrence of the pleural effusion using chest radiograph. They were clinically evaluated for chest pain and/or dyspnea and fever using a questionnaire that completed by the surgeon. The results were compared with two groups.

RESULTS

During this trial, 50 patients with MPE candidate for pleurodesis were selected and randomized into two interventional groups (25 patients in each group). Immediate and late recurrence of pleural effusion after pleurodesis were similar in two groups (P > 0.05). All patients in tetracycline group had fever and chest pain, but in SN group fever and chest pain were reported in 3 (12%) and 12 (48%) of patients, respectively (P < 0.05).

CONCLUSION

SN is at least as effective as tetracycline for MPE treatment. In addition, its side effects were lower than tetracycline. Other advantages of SN are its low cost, availability, and safety. For more accurate results, it is recommended to design further trials with larger sample size and with lower doses of both SN and tetracycline.

Immune Regulation of Interleukin-27 in Malignant Pleural Effusion

BACKGROUND

Interleukin (IL)-27 has been reported to have anti-proliferate and anti-angiogenic activities on cancer cells. However, the involvement of IL-27 in malignant pleural effusion (MPE) remains unknown. Thus, in this research, we compared the immune functions of IL-27, interferon (IFN)-γ, and IL-17 on lung cancer cells and revealed the regulatory mechanism of IL-27 in MPE.

METHODS

The distribution of IL-27 in both MPE and blood was evaluated by enzyme-linked immunosorbent assay and flow cytometry. The expressions of cytokine receptors and the levels of the phosphorylated signal transducer and activator of transcription (STAT) signalings were detected by flow cytometry. As well as the effects of proliferation, apoptosis, migration, and adherent activity of IL-27, IFN-γ, and IL-17 on lung cancer cells were also explored.

RESULTS

The expression of IL-27 was increased in MPE when compared with blood (147.3 ± 25.1 pg/ml vs. 100.3 ± 13.9 pg/ml, P = 0.04). IL-27 was noted to suppress both proliferation (18.33 ± 0.21 vs. 27.77 ± 0.88, P = 0.0005) and migration (1.82 ± 0.44 vs. 3.13 ± 0.07, P = 0.04) of A549 cells, but obviously promoted apoptosis of A549 cells (9.47 ± 1.14 vs. 4.96 ± 0.17, P = 0.02) by activating STAT1 signaling. Interestingly, IL-27 played totally opposite effects on A549 cells by activating STAT3 pathway. Moreover, IL-27 exerted different intercellular adherent activities of A549 cells to pleural mesothelial cell monolayer by activating different STAT signalings.

CONCLUSIONS

IL-27 might exert an important immune regulation on lung cancer cells in human pleural malignant environment.

Switching off malignant pleural effusion formation-fantasy or future?

Malignant pleural effusion (MPE) is common and difficult to treat. In the vast majority of patients the presence of MPE heralds incurable disease, associated with poor quality of life, morbidity and mortality. Current therapeutic approaches are inefficient and merely offer palliation of associated symptoms. Recent scientific progress has shed light in the biologic processes governing the mechanisms behind the pathobiology of MPE. Pleural based tumors interfere with pleural fluid drainage, as well as the host vasculature and immune system, resulting in decreased fluid absorption and increased pleural fluid production via enhanced plasma extravasation into the pleural space. In order to achieve this feat, pleural based tumors must elicit critical vasoactive events in the pleura, thus forming a favorable microenvironment for tumor dissemination and MPE development. Such properties involve specific transcriptional signaling cascades in addition to secretion of important mediators which attract and activate host cell populations which, in turn, impact tumor cell functions. The dissection of the biologic steps leading to MPE formation provides novel therapeutic targets and recent research findings provide encouraging results towards future therapeutic innovations in MPE management.

Pleural involvement in lung cancer

The pleural space, a sterile secluded environment in the thoracic cavity, represents an attractive metastatic site for various cancers of lung, breast and gastrointestinal origins. Whereas lung and breast adenocarcinomas could invade the pleural space because of their anatomic proximity, "distant" cancers like ovarian or gastrointestinal tract adenocarcinomas may employ more active mechanisms to the same end. A pleural metastasis is often accompanied by a malignant pleural effusion (MPE), an unfavorable complication that severely restricts the quality of life and expectancy of the cancer patient. MPE is the net "product" of three different processes, namely inflammation, enhanced angiogenesis and vascular leakage. Current efforts are focusing on the identification of cancer cell autocrine (specific mutation spectra and biochemical pathways) and paracrine (cytokine and chemokine signals) characteristics as well as host features (immunological or other) that underlie the MPE phenotype. Herein we examine the pleural histology, cytology and molecular characteristics that make the pleural cavity an attractive metastasis destination for lung adenocarcinoma. Mesothelial and tumor features that may account for the tumor's ability to invade the pleural space are highlighted. Finally, possible therapeutic interventions specifically targeting MPE are discussed.

Intrapleural cisplatin for management of malignant pleural effusion in a patient with plasma cell leucaemia

Plasma cell leucaemia (PCL) is a rare aggressive form of multiple myeloma. It occasionally involves the pleura, causing malignant pleural effusion (MPE). MPE presents a management dilemma for physicians, given the different treatment options available with varying efficacy and side effects. We report a case of a 64-year-old man with MPE due to PCL, successfully managed with intrapleural cisplatin and a tunnelled pleural catheter. We believe this to be the first report of management of PCL-associated MPE with intrapleural cisplatin.

Important prognostic factors for survival in patients with malignant pleural effusion

BACKGROUND

The approach to palliative treatment of malignant pleural effusion (MPE) should be individualized because these patients generally have poor survival. Our study aimed to develop a model to identify prognostic factors or survival time in patients diagnosed with MPE.

METHODS

This is a retrospective, descriptive, observational study to identify prognostic factors related to MPE in patients with a confirmed cancer diagnosis. Cox regression analysis was used to determine significant potential prognostic factors with respect to survival time. Survival time was defined as the time from pathological diagnosis to death.

RESULTS

One hundred and sixty-five patients were included; 77 were men (47%) and 88 were women (53%). The median age was 60 years, and all of the patients were pathologically proven to have MPE. Non-small-cell lung cancer (36.0%), breast carcinoma (26%), and lymphoma (13.0%) were the most frequently diagnosed tumors. The median overall survival of patients from the initial diagnosis was 5 months (range: 1.0-96.0 months). Kaplan-Meier univariate analysis showed that survival was significantly related to the following prognostic factors: ECOG PS (hazard ratio [HR] 10.0, 95% confidence interval [95% CI] 5.96 to 18.50, p < 0.0001), primary cancer site (HR 1.99, 95% CI 1.23 to 3.22, p < 0.01), positive pleural cytology (HR 1.25, 95% CI 0.88 to 1.78, p = 0.04), and positive histology (HR 1.33, 95% CI 0.97 to 1.81, p = 0.04). Other potential independent diagnostic factors that were examined did not affect survival. Cox regression analysis showed that only the ECOG PS was highly predictive of survival (HR 73.58, 95% CI 23.44 to 230.95, p < 0.0001).

CONCLUSIONS

ECOG PS is an independent predictor of survival in patients with MPE at initial diagnosis. This prognostic factor can help physicians select patients for appropriate palliative treatment of this syndrome.

Diagnostic value of survivin for malignant pleural effusion: a clinical study and meta-analysis

OBJECTIVE

To investigate the diagnostic accuracy of survivin for malignant pleural effusion (MPE).

METHODS

Pleural effusion samples were collected from 40 MPE patients and 45 non-MPE patients. Pleural levels of survivin were measured by ELISA. Literature search was performed in Pubmed and Embase to identify studies regarding the usefulness of survivin to diagnose MPE. Data were retrieved and the pooled sensitivity, specificity and other diagnostic indexes were calculated. The summary receiver operating characteristics (SROC) curve was used to determine the overall diagnostic accuracy.

RESULTS

The pleural levels of survivin were higher in MPE patients than non-MPE patients (844.17 ± 358.30 vs. 508.08 ± 169.58 pg/ml, P < 0.05), at a cut-off value of 683.2 pg/ml, the sensitivity and specificity were 57.50% and 88.89%, respectively. A total of six studies were included in present meta-analysis, the overall diagnostic estimates were: sensitivity 0.74 (95% CI: 0.59-0.85); specificity, 0.85 (95% CI: 0.79-0.89); positive likelihood ratio, 4.79 (95% CI: 3.48-6.61); negative likelihood ratio, 0.31 (95% CI: 0.19-0.50), and diagnostic odds ratio, 15.59 (95% CI: 7.69-31.61). The area under SROC curve was 0.86 (95% CI: 0.82-0.89).

CONCLUSION

Our study confirms that the pleural survivin plays a role in the diagnosis of MPE. More studies at a large scale should be performed to validate our findings.