Vascular endothelial growth factor: the key mediator in pleural effusion formation

Immune modulation in malignant pleural effusion: from microenvironment to therapeutic implications

Immune microenvironment and immunotherapy have become the focus and frontier of tumor research, and the immune checkpoint inhibitors has provided novel strategies for tumor treatment. Malignant pleural effusion (MPE) is a common end-stage manifestation of lung cancer, malignant pleural mesothelioma and other thoracic malignancies, which is invasive and often accompanied by poor prognosis, affecting the quality of life of affected patients. Currently, clinical therapy for MPE is limited to pleural puncture, pleural fixation, catheter drainage, and other palliative therapies. Immunization is a new direction for rehabilitation and treatment of MPE. The effusion caused by cancer cells establishes its own immune microenvironment during its formation. Immune cells, cytokines, signal pathways of microenvironment affect the MPE progress and prognosis of patients. The interaction between them have been proved. The relevant studies were obtained through a systematic search of PubMed database according to keywords search method. Then through screening and sorting and reading full-text, 300 literatures were screened out. Exclude irrelevant and poor quality articles, 238 literatures were cited in the references. In this study, the mechanism of immune microenvironment affecting malignant pleural effusion was discussed from the perspectives of adaptive immune cells, innate immune cells, cytokines and molecular targets. Meanwhile, this study focused on the clinical value of microenvironmental components in the immunotherapy and prognosis of malignant pleural effusion.

Case Report: Long-term remission of malignant pleural and peritoneal effusion in a case of advanced lung adenocarcinoma treated with combined crizotinib and anlotinib therapy

Malignant pleural and peritoneal effusion are common clinical manifestations in advanced malignant tumors, associated with a poor prognosis. This article presents a case of advanced lung adenocarcinoma with ROS1 rearrangement, characterized by persistent malignant pleural and peritoneal effusion. The patient received combined therapy of Crizotinib and Anlotinib, resulting in a significant reduction and even disappearance of the malignant effusion. Exploratory use of this treatment approach improved the patient's quality of life and holds potential for extending overall survival. However, given the single case report nature, the efficacy of this regimen in treating advanced ROS1-rearranged lung adenocarcinoma should be considered as a supplementary strategy, warranting further validation through multicenter clinical data.

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.

Role of GSDMD and VEGF in differentiating between malignant and non-malignant pleural effusions

Background

It is crucial to differentiate between benign and malignant pleural effusions while making a diagnosis. The purpose of this research was to investigate the diagnostic significance of GSDMD and VEGF in discriminating between different kinds of pleural effusion and their correlation with both progression-free and overall survivals in the malignant type.

Methods

Ninety-one pleural fluid samples, which were classified as transudates or exudates (tuberculous, para-infectious, or malignant) by pleural fluid classifications, were tested for GSDMD using sandwich ELIZA kits, and 41 of the exudative samples were randomly selected for VEGF testing. Both markers' diagnostic accuracy was assessed.

Results

The lowest level of GSDMD was associated with the transudate group (mean and SD of 2.35 ± 0.44 ng/mL) and the highest in the malignant effusion group (mean and SD of 4.38 ± 1.67 ng/mL). The specificity and sensitivity of GSDMD in the diagnosis of exudative PE were 97% and 98%, respectively (p = 0.001) with the cutoff point = 2.89). Regarding VEGF, its level was 222.3 ± 53.4 pg/ml for all studied samples where MPE (n = 21) was 261.2 ± 48.2 pg/ ml (mean ± SD), TBPE (n = 7) was 185.4 ± 6.96 pg/ml (mean ± SD), and PIPE (n = 13) was 179.3 ± 13.9 pg/ml (mean ± SD). The diagnostic accuracy of VEGF for the detection of MPE was 90% with a sensitivity of 100% and specificity of 80% and the cutoff point was 191.5 pg/ml. There were highly significant inverse correlations between progression-free survival and both GSDMD (r =− 0.531, p = 0.009) and VEGF (r = − 0.582, p = 0.006) in MPE.

Conclusion

Pleural effusion GSDMD can be an effective marker for differentiating the different kinds of PE, and VEGF levels can be a useful adjuvant marker in screening out MPE as a possible diagnosis, leading to the proper selection of patients who may benefit from more invasive procedures.

Treatment of malignant pleural effusion in non-small cell lung cancer with VEGF-directed therapy

BACKGROUND

Vascular endothelial growth factor (VEGF) is a critical regulator of malignant pleural effusion (MPE) in non-small-cell lung cancer (NSCLC). Bevacizumab (BEV) and apatinib (APA) are novel VEGF blockers that inhibit lung cancer cell proliferation and the development of pleural effusion.

METHODS

In this study, we established Lewis lung cancer (LLC) xenograft mouse models to compare the therapeutic effect of APA and BEV in combination with cisplatin (CDDP) against MPE. The anti-tumour and anti-angiogenic effects of this combination therapy were evaluated by ¹⁸F-FDG PET/CT imaging, TUNEL assay and Immunohistochemistry.

RESULTS

The triple drug combination significantly prolonged the overall survival of the tumour-bearing mice by reducing MPE and glucose metabolism and was more effective in lowering VEGF/soluble VEGFR-2 levels in the serum and pleural exudates compared to either of the monotherapies. Furthermore, CDDP + APA + BEV promoted in vivo apoptosis and decreased microvessel density.

CONCLUSIONS

Mechanistically, LLC-induced MPE was inhibited by targeting the VEGF-MEK/ERK pathways. Further studies are needed to establish the synergistic therapeutic effect of these drugs in NSCLC patients with MPE.KEY MESSAGESCombined treatment of MPE with apatinib, bevacizumab and cisplatin can prolong the survival time of mice, reduce the content of MPE, decrease the SUV_max of thoracic tumour tissue, down-regulate the content of VEGF and sVEGFR-2 in serum and pleural fluid, and promote the apoptosis of tumour cells. Angiogenesis and MPE formation can be inhibited by down-regulation of HIF-1α, VEGF, VEGFR-2, MEK1 and MMP-2 molecular signalling pathway proteins.

Efficacy of Immune Checkpoint Inhibitor With or Without Chemotherapy for Non–Squamous Non-Small Cell Lung Cancer with Malignant Pleural Effusion: A Retrospective Multicenter Cohort Study

Introduction

Malignant pleural effusion (MPE) is associated with poor treatment outcome in patients with NSCLC receiving immune checkpoint inhibitors (ICIs). ICIs and chemotherapy (ICI/Chemo) combination therapy is currently the standard therapy for NSCLC, and some ICI/Chemo regimens for nonsquamous (non-Sq) NSCLC contain bevacizumab (BEV), which is effective for controlling MPE and may enhance immune response. This study aimed to determine the optimal first-line treatment for this clinical population.

Methods

We retrospectively enrolled consecutive patients with non-Sq NSCLC with MPE who received ICI/Chemo or pembrolizumab monotherapy. Treatment outcomes were analyzed in patients with programmed death-ligand 1 (PD-L1) tumor proportion score more than or equal to 50% who were administered ICI/Chemo or pembrolizumab monotherapy (PD-L1 high cohort) and in patients with any PD-L1 status, treated with ICI/Chemo with or without BEV (ICI/Chemo cohort). We used propensity score matching (PSM) to reduce bias.

Results

PD-L1 high and ICI/Chemo cohorts included 143 and 139 patients, respectively. In PD-L1 high cohort, 37 patients received ICI/Chemo. With PSM, the median progression-free survival was significantly longer in the ICI/Chemo group than in the pembrolizumab group (11.1 versus 3.9 mo, respectively, p = 0.0409). In the ICI/Chemo cohort, 23 patients received BEV. With PSM, no significant difference occurred in median progression-free survival between BEV and non-BEV groups (6.1 versus 7.4 mo, p = 0.9610).

Conclusion

ICI/Chemo seemed more effective than pembrolizumab monotherapy for patients with non-Sq NSCLC with MPE. Nevertheless, the synergistic effect of BEV with ICI/Chemo may be limited. Further studies are needed to clarify the key factor in the tumor-induced immunosuppression environment in these patients.

Steroid Therapy and Outcome of Parapneumonic Pleural Effusions (STOPPE): A Pilot Randomized Clinical Trial

Rationale: Pleural effusion commonly complicates community-acquired pneumonia and is associated with intense pleural inflammation. Whether antiinflammatory treatment with corticosteroids improves outcomes is unknown. Objectives: To assess the effects of corticosteroids in an adult population with pneumonia-related pleural effusion. Methods: The STOPPE (Steroid Therapy and Outcome of Parapneumonic Pleural Effusions) trial was a pilot, multicenter, double-blinded, placebo-controlled, randomized trial involving six Australian centers. Patients with community-acquired pneumonia and pleural effusion were randomized (2:1) to intravenous dexamethasone (4 mg twice daily for 48 h) or placebo and followed for 30 days. Given the diverse effects of corticosteroids, a comprehensive range of clinical, serological, and imaging outcomes were assessed in this pilot trial (ACTRN12618000947202). Measurements and Main Results: Eighty patients were randomized (one withdrawn before treatment) and received dexamethasone (n = 51) or placebo (n = 28). This pilot trial found no preliminary evidence of benefits of dexamethasone in improving time to sustained (>12 h) normalization of vital signs (temperature, oxygen saturations, blood pressure, heart, and respiratory rates): median, 41.0 (95% confidence interval, 32.3-54.5) versus 27.8 (15.4-49.5) hours in the placebo arm (hazard ratio, 0.729 [95% confidence interval, 0.453-1.173]; P = 0.193). Similarly, no differences in C-reactive protein or leukocyte counts were observed, except for a higher leukocyte count in the dexamethasone group at Day 3. Pleural drainage procedures were performed in 49.0% of dexamethasone-treated and 42.9% of placebo-treated patients (P = 0.60). Radiographic pleural opacification decreased over time with no consistent intergroup differences. Mean duration of antibiotic therapy (22.4 [SD, 15.4] vs. 20.4 [SD, 13.8] d) and median hospitalization (6.0 [interquartile range, 5.0-10.0] vs. 5.5 [interquartile range, 5.0-8.0] d) were similar between the dexamethasone and placebo groups. Serious adverse events occurred in 25.5% of dexamethasone-treated and 21.4% of placebo-treated patients. Transient hyperglycemia more commonly affected the dexamethasone group (15.6% vs. 7.1%). Conclusions: Systemic corticosteroids showed no preliminary benefits in adults with parapneumonic effusions. Clinical trial registered with www.anzctr.org.au (ACTRN12618000947202).

A phase II study of bevacizumab in non-squamous, non-small-cell lung cancer patients with malignant pleural effusion

Aim: To investigate the efficacy, safety and optimal dosage of bevacizumab in non-squamous, non-small-cell lung cancer (NSCLC) patients with malignant pleural effusion (MPE). Methods: 20 patients were enrolled and received intrapleural injection of bevacizumab (group A: 2.5 mg/kg d1, d8; group B: 5 mg/kg d1, d8; group C: 7.5 mg/kg d1, d8). Results: The objective control rate (ORR) of MPE was 50%. The median progression-free survival (PFS) of MPE was 7.0 months (95% CI 4.9-9.2). The ORR and PFS of MPE from group B were better than those of group A and group C. The most common adverse events (AEs) were hypertension (15%) and anemia (15%). Conclusion: Bevacizumab has certain efficacy in non-squamous NSCLC patients with MPE. Clinical Trial Registration: NCT02942043 (ClinicalTrials.gov).

Neutrophil-to-lymphocyte ratio in malignant pleural fluid: Prognostic significance

Predicting survival of patients with malignant pleural effusions (MPEs) is notoriously difficult. A robust prognostic marker can guide clinical decision making. The neutrophil-to-lymphocyte ratio (NLR) in blood has been shown to predict survival in many cancers. Pleural fluid bathes the malignant pleural tissues, thus the NLR of the pleural fluid may reflect more closely the local tumour environment. The objective of this study was to explore the prognostic significance of pleural effusion NLR for MPE. We analysed matched effusion and blood from 117 patients with malignant and 24 with benign pleural effusions. Those who had received recent chemotherapy or had a pleurodesis were excluded. Neutrophil and lymphocyte counts in effusions were performed by manual review of cytospin cell preparations by trained observers. Clinical data were extracted from a state-wide hospital database. We found significantly fewer neutrophils (expressed as percentage of total leukocyte count) in pleural fluid than in corresponding blood (9% vs 73%; p<0.001). The NLR was an order of magnitude lower in pleural fluid than in corresponding blood: median [IQR] = 0.20 [0.04-1.18] vs 4.9 [3.0-8.3], p<0.001. Correlation between blood and pleural fluid NLR in MPE patients was moderate (rs = 0.321, p<0.001). In univariate analysis, NLR (>0.745)) in malignant pleural fluid was predictive of poorer survival (HR = 1.698 [1.0054-2.736]; p = 0.030), and remained significant after adjustment for age, sex, presence of a chest drain, cancer type, concurrent infection and subsequent treatment with chemotherapy (HR = 1.786 [1.089-2.928]; p = 0.022). Patients with pleural fluid NLR > 0.745 had a significantly shorter median survival of 130 (95% CI 0-282) days compared to 312 (95% CI 195-428) days for pleural NLR < 0.745, p = 0.026. The NLR in blood was also predictive of poorer survival in MPE patients (HR = 1.959 [1.019-3.096]; p<0.001). The proportion of neutrophils in pleural fluid was predictive of prognosis more strongly than lymphocytes. This study provides evidence that NLR in malignant effusions can predict survival, and therefore may provide prognostic information for this cohort. This prognostic association in the fluid is driven by the presence of neutrophils.

Clinically relevant prognostic and predictive markers for immune-checkpoint-inhibitor (ICI) therapy in non-small cell lung cancer (NSCLC)

BACKGROUND

Immune checkpoint inhibitors (ICI) either alone or in combination with chemotherapy have expanded our choice of agents for the palliative treatment of non-small cell lung cancer (NSCLC) patients. Unfortunately, not all patients will experience favorable response to treatment with ICI and may even suffer from severe side effects. Therefore, prognostic and predictive markers, beyond programmed death ligand 1 (PD-L1) expression status, are of utmost importance for decision making in the palliative treatment. This review focuses on clinical, laboratory and genetic markers, most of them easily to obtain in the daily clinical practice.

RESULTS

Recently, a number of prognostic and predictive factors in association to palliative ICI therapy have been described in NSCLC. Besides biometric parameters and clinical characteristics of the tumor, there are useful markers from routine blood sampling as well as innovative soluble genetic markers which can be determined before and during ICI treatment. Additionally, the level of evidence is noted.

CONCLUSIONS

These factors can be helpful to predict patients' outcome and tumor response to ICI. They should be implemented prospectively in ICI based clinical trials to develop reliable algorithms for palliative NSCLC treatment.

Pleural Fluid Cytokine Levels at Baseline and Over Time are Associated With Time to IPC Removal: An Exploratory Study

BACKGROUND

The behavior of pleural fluid cytokine (PFCs) levels and their association with pleurodesis after indwelling pleural catheter (IPC) placement is unknown.

OBJECTIVE

A prospective exploratory study was conducted to obtain preliminary data on PFC levels after IPC placement.

METHODS

The PFC panel consisted of 4 cytokines [interleukin -8 (IL-8), vascular endothelial growth factor, total (but not activated) transforming growth factor betas, and basic fibroblast growth factor], measured across 5 time points (T0: insertion; T1: 24 to 48 h; T2: 72 to 96 h; T3: 1 wk; and T4: 2 wk). Profile plots were used to identify patterns of change of PFC levels. Correlation matrices for each PFC over time were computed, and area under the curve (AUC) categories were used to compare the cumulative incidence of IPC removal. Auto pleurodesis was defined as elective catheter removal because of decreased drainage within 90 days of insertion.

RESULTS

A total of 22 patients provided complete data. Except for IL-8, the majority of PFCs demonstrated strong positive correlations across measurement time points. Patients with high AUCs for IL-8, basic fibroblast growth factor, and vascular endothelial growth factor had a higher cumulative incidence of IPC removal by 90 days than did patients with low AUCs.

CONCLUSION

This is the first study to evaluate longitudinal changes of pleural cytokine levels with respect to the likelihood of IPC removal and provide early evidence that the cytokine profile may be associated with the outcome of pleurodesis induced by IPCs. However, this is an exploratory study and further studies are needed to assess if these findings can be validated in further studies.

Thoracoscopy and talc poudrage compared with intercostal drainage and talc slurry infusion to manage malignant pleural effusion: the TAPPS RCT

BACKGROUND

There are around 40,000 new cases of malignant pleural effusion in the UK each year. Insertion of talc slurry via a chest tube is the current standard treatment in the UK. However, some centres prefer local anaesthetic thoracoscopy and talc poudrage. There is no consensus as to which approach is most effective.

OBJECTIVE

This trial tested the hypothesis that thoracoscopy and talc poudrage increases the proportion of patients with successful pleurodesis at 3 months post procedure, compared with chest drain insertion and talc slurry.

DESIGN

This was a multicentre, open-label, randomised controlled trial with embedded economic evaluation. Follow-up took place at 1, 3 and 6 months.

SETTING

This trial was set in 17 NHS hospitals in the UK.

PARTICIPANTS

A total of 330 adults with a confirmed diagnosis of malignant pleural effusion needing pleurodesis and fit to undergo thoracoscopy under local anaesthetic were included. Those adults needing a tissue diagnosis or with evidence of lung entrapment were excluded.

INTERVENTIONS

Allocation took place following minimisation with a random component, performed by a web-based, centralised computer system. Participants in the control arm were treated with a bedside chest drain insertion and 4 g of talc slurry. In the intervention arm, participants underwent local anaesthetic thoracoscopy with 4 g of talc poudrage.

MAIN OUTCOME MEASURES

The primary outcome measure was pleurodesis failure at 90 days post randomisation. Secondary outcome measures included mortality and patient-reported symptoms. A cost-utility analysis was also performed.

RESULTS

A total of 166 and 164 patients were allocated to poudrage and slurry, respectively. Participants were well matched at baseline. For the primary outcome, no significant difference in pleurodesis failure was observed between the treatment groups at 90 days, with rates of 36 out of 161 (22%) and 38 out of 159 (24%) noted in the poudrage and slurry groups, respectively (odds ratio 0.91, 95% confidence interval 0.54 to 1.55; p = 0.74). No differences (or trends towards difference) were noted in adverse events or any of the secondary outcomes at any time point, including pleurodesis failure at 180 days [poudrage 46/161 (29%), slurry 44/159 (28%), odds ratio 1.05, 95% confidence interval 0.63 to 1.73; p = 0.86], mean number of nights in hospital over 90 days [poudrage 12 nights (standard deviation 13 nights), slurry 11 nights (standard deviation 10 nights); p = 0.35] and all-cause mortality at 180 days [poudrage 66/166 (40%), slurry 68/164 (42%); p = 0.70]. At £20,000 per quality-adjusted life-year gained, poudrage would have a 0.36 probability of being cost-effective compared with slurry.

LIMITATIONS

Entry criteria specified that patients must be sufficiently fit to undergo thoracoscopy, which may make the results less applicable to those patients presenting with a greater degree of frailty. Furthermore, the trial was conducted on an open-label basis, which may have influenced the results of patient-reported measures.

CONCLUSIONS

The TAPPS (evaluating the efficacy of Thoracoscopy And talc Poudrage versus Pleurodesis using talc Slurry) trial has robustly demonstrated that there is no additional clinical effectiveness or cost-effectiveness benefit in performing talc poudrage at thoracoscopy over bedside chest drain and talc slurry for the management of malignant pleural effusion.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN47845793.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 26. See the NIHR Journals Library website for further project information.

Association between metastatic sites and first-line pembrolizumab treatment outcome for advanced non-small cell lung cancer with high PD-L1 expression: a retrospective multicenter cohort study

Associations between treatment outcomes of immune checkpoint inhibitors and metastatic sites in advanced non-small cell lung cancer (NSCLC) are not well known. Therefore, this multicenter retrospective study aimed to investigate the predictive factors of metastatic sites after first-line pembrolizumab treatment for advanced NSCLC with a PD-L1 tumor proportion score (TPS) ≥50%. We retrospectively analyzed advanced NSCLC patients with a PD-L1 TPS ≥50% who underwent first-line pembrolizumab therapy at 11 institutions between February 2017 and April 2018. Clinical data collected from medical records included metastatic sites at the time of pembrolizumab treatment. Treatment outcomes of pembrolizumab were assessed according to the Response Evaluation Criteria in Solid Tumors, version 1.1. In total, 213 patients were included in the study. The median age was 71 years (range 39-91 years). Of the 213 patients, 176 (83%) were men and 172 (81%) had an Eastern Cooperative Oncology Group performance status (ECOG-PS) score of 0-1. The most common metastases were thoracic lymph node metastasis (77%), intrapulmonary metastasis (31%), bone metastasis (28%), and malignant pleural effusion (26%). On multivariate analysis, a poor ECOG-PS score (hazard ratio: 1.95, 95.0% confidence interval: 1.25-3.04; P = 0.003) and malignant pleural effusion (hazard ratio: 1.52, 95.0% confidence interval: 1.01-2.29; P = 0.043) were independent predictors of shorter progression-free survival in patients treated with pembrolizumab. For NSCLC patients with malignant pleural effusion, pembrolizumab monotherapy is not a suitable first-line treatment because of its insufficient effectiveness, even though their PD-L1 TPS was high.

A randomized clinical study to compare intrapleural infusion with intravenous infusion of bevacizumab in the management of malignant pleural effusion in patients with non-small-cell lung cancer

BACKGROUND

To compare the efficiency and toxicity of bevacizumab by intrapleural or intravenous infusion in the management of malignant pleural effusion in patients with non-small-cell lung cancer (NSCLC).

METHODS

Sensitizing mutation negative NSCLC patients with malignant pleural effusion were randomized into two groups in 1:1 ratio. The pleural effusion was completely drained in 24 hours; one group received intrapleural infusion and the second group received intravenous infusion of bevacizumab at a dose of 7.5 mg per kg bodyweight. The serum vascular endothelial growth factor (VEGF) was tested before and 72 hours after injection of bevacizumab. Computerized tomography (CT) scan to evaluate pleural effusions was carried out at four weeks for each patient and their survival followed-up.

RESULTS

A total of 67 patients were screened and 43 enrolled into the study. The response rate was 80% (16 of 20) in the intrapleural group and 66.7% (14 of 21) in the intravenous group. The median duration of response (DoR) of pleural effusion was 4.50 months and 3.70 months, respectively. The median serum VEGF level at 72 hours decreased 67.25% in the intrapleural group and 57.19% in the intravenous group compared to baseline level (P = 0.276). The median serum VEGF level at 72 hours decreased 52.02% compared to baseline level in patients' DoR less than three months and 68.33% in patients' DoR longer than three months, respectively (P = 0.014). The main side effects noted were mild to moderate hypertension, proteinuria and epistaxis.

CONCLUSIONS

Bevacizumab intrapleural infusion had higher efficiency and higher safety than intravenous infusion in the management of malignant pleural effusion caused by NSCLC. The decreased level of serum VEGF at 72 hours after bevacizumab treatment was closely related to the response rate and duration of the response of pleural effusion.

A Retrospective Study of Ultrasound Characteristics and Macroscopic Findings in Confirmed Malignant Pleural Effusion

Background

A definitive diagnosis of malignant pleural effusion (MPE) is reached by cytological or histological assessment, but thorough analysis of the ultrasound features of the effusion as well as pleural thickening or nodularity can also be of significant diagnostic help.

Objective

To assess the relationship of specific ultrasound characterisctics and macroscopic features of confirmed malignant pleural effusion, thus increasing the diagnostic potential of thoracic ultrasound.

Methods

The findings of thoracic ultrasonography performed prior to initial thoracentesis in 104 patients with subsequently confirmed malignant pleural effusion were analyzed with regard to the macroscopic features of the pleural effusion.

Results

Distribution in terms of frequency of hemorrhagic/sanguinolent (n=64) in relation to nonhemorrhagic transparent/opaque (n=40) MPE, regardless of their ultrasound characteristics, did not yield a statistically significant correlation (p=0.159). Conversely, the frequency distribution of hemorrhagic pleural effusions (n=8) in relation to nonhemorrhagic effusions (n=1), in the group of septated MPE, showed a statistically significant difference (p<0.001). The least number of patients (0.96%) had a complex septated MPE combined with the macroscopic appearance of a serous/transparent nonhemorrhagic effusion, which suggests that this combination is a sporadic occurrence and may have a diagnostic significance for this patient group.

Conclusion

The incidence of specific combinations of the ultrasound characteristics and macroscopic appearance of MPEs showed different frequency distributions, which may improve the diagnostic value of thoracic ultrasound in this patient population.

Better efficacy of intrapleural infusion of bevacizumab with pemetrexed for malignant pleural effusion mediated from nonsquamous non-small cell lung cancer

Background and objective

Several clinical trials have reported that intrapleural infusion of bevacizumab with or without cisplatin exhibits encouraging efficacy in nonsquamous non-small cell lung cancer (NS-NSCLC) patients with malignant serous cavity effusion. However, most of the studies included a number of different types of cancers or different hydrops types rather than focusing on one. In addition, no study reported the efficacy and toxicity of intrapleural infusion of bevacizumab and pemetrexed for advanced NS-NSCLC patients with malignant pleural effusion (MPE).

Patients and methods

We retrospectively collected patients with MPE mediated from NS-NSCLC who underwent intrapleural infusion of bevacizumab between August 2012 and February 2017. According to the different combined agents with bevacizumab, we divide patients into two groups: Group 1 (BP Group) intrapleural infusion of bevacizumab combined with pemetrexed and Group 2 (BD group) intrapleural infusion of bevacizumab combined with cisplatin.

Results

A total of 45 patients were enrolled in this study. Twenty-two of them received intrapleuralinfusion of bevacizumab and pemetrexed every 2 weeks, 23 received bevacizumab and cisplatin after draining effusion as much as possible. The progression-free survival for patients in BP group was significantly higher than BD group (P < 0.05) while the overall survival between the two groups was not significantly different (P > 0.05). In addition, there was no statistical difference in adverse effects between two groups.

Conclusion

Intrapleural infusion of bevacizumab and pemetrexed is effective and tolerable for patients with MPE mediated from NSCLC.

Greater efficacy of intracavitary infusion of bevacizumab compared to traditional local treatments for patients with malignant cavity serous effusion

Intracavitary infusion of bevacizumab is one effective treatment for malignant serous cavity effusion (MSCE). In this study, we retrospectively evaluated the efficacy of local treatments in 996 advanced cancer patients with MSCE who received paracentesis and intracavitary bevacizumab, or chemotherapy, biological response modifiers, or simple puncture to drain the effusion. The median progression-free survival (PFS) time in patients treated with bevacizumab was 189 days (range, 13-522 days), which was longer than in patients who received one of the other three treatments (p < 0.05). Subgroup analysis revealed that intracavitary infusion of bevacizumab was advantageous for patients with malignant pleural, pericardial, or peritoneal effusions. The median PFS in patients receiving intracavitary bevacizumab did not significantly differ from that of patients receiving a combination of intracavitary and intravenous bevacizumab. Thus the efficacy did not depend on whether patients received intravenous bevacizumab. Only mild related adverse events were observed in all cases, and they did not differ between groups. Proteinuria (severity grade < 3) was most likely to occur in patients who received a combination of intracavitary and intravenous bevacizumab, but no obvious symptoms were observed. Thus, intracavitary infusion of bevacizumab was effective for controlling MSCE without apparent toxicity.

Role of bevacizumab in the management of the patient with malignant pleural effusion: more questions than answers

INTRODUCTION

Malignant pleural effusion (MPE) is a feature of metastatic cancer associated with significant morbidity and cost. The typical management of MPE is systemic chemotherapy and mechanical intervention. Vascular endothelial growth factor (VEGF), an inducer of vascular permeability, has been shown to mediate fluid formation. Therefore, bevacizumab, an inhibitor of VEGF, offers theoretical promise for abolishing fluid formation in MPE. Areas covered: This review begins with a summary of VEGF physiology and evidence of its role in MPE pathogenesis. This is followed by an overview of bevacizumab and major trials that put it on the map of non-small cell lung cancer (NSCLC). The majority of the article is devoted to a review of the current evidence base for the use of bevacizumab for MPE control in metastatic pleural malignancy. The review concludes with considerations of patient selection and toxicity. Expert commentary: Evidence in support of bevacizumab administration for MPE management remains flawed. Small studies suggest efficacy of both intravenous and intrapleural routes, but their design raises bias concerns. Bevacizumab appears to be safe in properly selected cases. The future of MPE management may de-emphasize VEGF inhibition in favor of precise molecular therapeutics that could address the root cause of tumorigenesis.

The importance of serum and pleural fluid level of vascular endothelial growth factor (VEGF) and VEGF fluid/serum ratio in the differential diagnosis of malignant mesothelioma-related pleural effusion

Aim of the study

Vascular endothelial growth factor (VEGF) is one of the parameters that has been studied in differential diagnosis of malignant fluids. This study is aimed at evaluate applicability of serum, fluid VEGF level and fluid to serum VEGF ratio in the diagnosis of malignant pleural mesothelioma (MPM).

Material and methods

The patients with pleural effusion over age of 18, between 2011 and 2015 were included in the study. They were divided into three groups: group 1 – mesothelioma patients; group 2 – other malignancies; and group 3 – benign aetiologies. Group 1 and 2 were termed as the malignant group. Fluid, serum VEGF levels, and the ratio of fluid/serum VEGF level were studied to evaluate the fluid/serum VEGF ratio in all groups.

Results

Twenty cases with mesothelioma, 44 cases with other malignancies, and 20 cases with benign aetiologies were included in this study. No statistically significant difference was found according to serum VEGF levels for all groups, (group 1: 437 ±324 pg/ml, group 2: 354 ±223 pg/ml, group 3: 373 ±217 pg/ml, p = 0.836), while fluid VEGF levels showed a statistically significant difference (group 1: 3359 ±700 pg/ml, group 2: 2175 ±435 pg/ml, group 3: 1092 ±435 pg/ml, p = 0.041). The ratio of fluid to serum VEGF levels showed a difference, at the significance limit, between the malignant (group 1 and group 2) and benign (group 3) groups (8.83 ±1.29 vs. 4.57 ±1.07, p = 0.059) but showed a statistically significant difference between the mesothelioma and benign groups (12.11 ±1.68 vs. 4.57 ±1.07, p = 0.044).

Conclusions

The VEGF fluid/serum ratio may be an applicable parameter in the differential diagnosis of malignant fluids, especially MPM.

Intrapleural targeted therapies (anti-VEGF and anti-EGFR) in the model of malignant pleural effusion

Rationale

Malignant pleural effusion has few options of treatment and drugs administrated by different routes can lead to a less permissive microenvironment for the development of malignant pleural disease.

Objectives

To analyze therapies administered intrapleurally in malignant pleural disease and to study EGFR and KRAS mutations in adenocarcinoma.

Methods

Mice received LLC cells and were treated intrapleurally with anti-VEGF, anti-EGFR, anti-VEGF+anti-EGFR or saline. Animal survival, weight and mobility, volume, biochemistry and immunology of fluid, gene expression, KRAS and EGFR mutation were evaluated.

Results

All animals developed malignant effusion and presented progressive weight loss without difference between groups; however, groups treated with anti-EGFR were more active. No difference in mortality was observed. Temporal increase of volume and inflammatory markers was observed mainly in the untreated group. Gene expression in tumors was overexpressed in VEGF, EGFR and KRAS compared with normal tissue. Mutation in exon 2 of the KRAS gene was observed.

Conclusions

Intrapleural Anti-VEGF and/or anti-EGFR reduced volume and inflammatory mediators in pleural fluid. Anti-EGFR and anti-VEGF+anti-EGFR decreased morbidity although without impact on survival. LLC tumors presented KRAS mutation, this could have influenced the action of these therapies.

Vascular endothelial growth factor and protein level in pleural effusion for differentiating malignant from benign pleural effusion

Pleural effusion is associated with multiple benign and malignant conditions. Currently no biomarkers differentiate malignant pleural effusion (MPE) and benign pleural effusion (BPE) sensitively and specifically. The present study identified a novel combination of biomarkers in pleural effusion for differentiating MPE from BPE by enrolling 75 patients, 34 with BPE and 41 with MPE. The levels of lactate dehydrogenase, glucose, protein, and total cell, neutrophil, monocyte and lymphocyte counts in the pleural effusion were measured. The concentrations of interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor-α, interferon γ, transforming growth factor-β1, colony stimulating factor 2, monocyte chemoattractant protein-1 and vascular endothelial growth factor (VEGF) were detected using cytometric bead arrays. Protein and VEGF levels differed significantly between patients with BPE and those with MPE. The optimal cutoff value of VEGF and protein was 214 pg/ml and 3.35 g/dl respectively, according to the receiver operating characteristic curve. A combination of VEGF >214 pg/ml and protein >3.35 g/dl in pleural effusion presented a sensitivity of 92.6% and an accuracy of 78.6% for MPE, but was not associated with a decreased survival rate. These results suggested that this novel combination strategy may provide useful biomarkers for predicting MPE and facilitating early diagnosis.

Bevacizumab for ramucirumab refractory malignant pleural effusion in non-small cell lung cancer: a case report and review of the literature

Malignant pleural effusion (MPE) is a major problem associated with advanced non-small cell lung cancer for which an optimum treatment strategy has yet to be determined. Notably, vascular endothelial growth factor (VEGF) signaling has been found to influence MPE, and bevacizumab, a VEGF ligand inhibitor, can effectively control MPE. Ramucirumab, a human monoclonal antibody specific for VEGF receptor-2, has recently been approved for advanced non-small cell lung cancer. However, it remains unclear which of these agents more effectively control MPE.We describe a case of a 68-year-old man with advanced non-small cell lung cancer in whom ramucirumab plus docetaxel-refractory MPE was responsive to bevacizumab plus docetaxel combination therapy. The patient's MPE progressed after two cycles of ramucirumab plus docetaxel second-line chemotherapy. After switching to bevacizumab plus docetaxel, a computed tomography scan revealed a decreased MPE after two cycles of treatment.Bevacizumab may be more effective for treating MPE. However, further investigations are still warranted to determine the optimal VEGF-targeted agent for this condition.

Effects of Combined Simultaneous and Sequential Endostar and Cisplatin Treatment in a Mice Model of Gastric Cancer Peritoneal Metastases

Objective. Aimed to study the effects of endostar and cisplatin using an in vivo imaging system (IVIS) in a model of peritoneal metastasis of gastric cancer. Methods. NUGC-4 gastric cancer cells transfected with luciferase gene (NUGC-4-Luc) were injected i.p. into nude mice. One week later, mice were randomly injected i.p.: group 1, cisplatin (d1-3) + endostar (d4-7); group 2, endostar (d1-4) + cisplatin (d5-7); group 3, endostar + cisplatin d1, 4, and 7; group 4, saline for two weeks. One week after the final administration, mice were sacrificed. Bioluminescent data, microvessel density (MVD), and lymphatic vessel density (LVD) were analyzed. Results. Among the four groups, there were no significant differences in the weights and in the number of cancer cell photons on days 1 and 8 (P > 0.05). On day 15, the numbers in groups 3 and 1 were less than that in group 2 (P < 0.05). On day 21, group 3 was significantly less than group 2 (P < 0.05). MVD of group 4 was less than that of groups 1 and 2 (P < 0.01). There was no significant difference between groups 2 and 3 (P > 0.05) or in LVD number among the four groups (P > 0.05). Conclusions. IVIS® was more useful than weight, volume of ascites, and number of peritoneal nodules. The simultaneous group was superior to sequential groups in killing cancer cells and inhibiting vascular endothelium. Cisplatin-endostar was superior to endostar-cisplatin in killing cancer cells, while the latter in inhibiting peritoneal vascular endothelium.

A potential role for VEGF in the diagnostic approach of pleural effusions

BACKGROUND

Vascular endothelial growth factor (VEGF) may play a role in pleural fluid formation, as it represents a potent inducer of capillary permeability. We aimed to investigate the diagnostic utility of VEGF levels in pleural fluid and serum in patients with pleural effusions with initially negative diagnostic work up.

METHODS

Seventy-one patients with exudative lymphocytic pleural effusions undiagnosed after initial diagnostic work up were enrolled in this prospective study and their clinical course was followed up to 24 months. VEGF levels were measured in serum and pleural fluid by using immunoenzymometric assay.

RESULTS

During the follow up period, in 43 patients the pleural effusion was eventually attributed to malignancy while in the rest 28 patients it was due to non-malignant causes (benign and unknown origin). Patients with malignancy had significantly higher VEGF levels in pleural fluid compared to patients with non-malignant effusions (1,506 vs. 588 pg/dL, P=0.0001), while no statistically significant difference was found in the VEGF serum levels between the two groups.

CONCLUSIONS

Pleural VEGF levels may be helpful in identifying malignant pleural effusion (MPE) in patients with negative diagnostic work up at the initial assessment and help in selecting patients for more invasive procedures.

Pleural fluid osteopontin, vascular endothelial growth factor, and urokinase-type plasminogen activator levels as predictors of pleurodesis outcome and prognosticators in patients with malignant pleural effusion: a prospective cohort study

BACKGROUND

Rapidly growing cancer cells secrete growth-promoting polypeptides and have increased proteolytic activity, contributing to tumor progression and metastasis. Their presentation in malignant pleural effusion (MPE) and their predictive value for the outcome of pleurodesis and survival were studied.

METHODS

Between February 2011 and March 2012, MPE samples were prospectively collected from 61 patients. Twenty-five patients with non-malignant pleural effusion in the same period were included as controls. Pleural fluid osteopontin (OPN), vascular endothelial growth factor (VEGF), and urokinase-type plasminogen activator (uPA) concentrations were measured.

RESULTS

Patients with MPE had higher pleural fluid OPN, VEGF, and uPA concentrations than those with non-malignant pleural effusion, but only differences in VEGF were statistically significant (p = 0.045). Patients with distant metastases had significantly elevated pleural fluid VEGF concentrations than those without (p = 0.004). Pleural fluid OPN, VEGF, and uPA concentrations were positively correlated in most patients. However, there was no significant difference in pleural fluid OPN, VEGF, and uPA concentrations between patients with successful pleurodesis and those without. There was also no significant difference in cancer-specific survival between sub-groups with higher and lower pleural fluid OPN, VEGF, or uPA concentrations. Patients with successful pleurodesis had significantly longer cancer-specific survival than those without (p = 0.015).

CONCLUSIONS

Pleural fluid OPN, VEGF, and uPA concentrations are elevated in MPE but are not satisfactory predictors of pleurodesis outcome or survival. Patients with higher pleural fluid VEGF concentration have higher risk of distant metastasis. Evaluating the benefits of therapy targeting the VEGF pathway in these patients warrants further studies.

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.

Polyacrylate/nanosilica causes pleural and pericardial effusion, and pulmonary fibrosis and granuloma in rats similar to those observed in exposed workers

Nanomaterials offer great benefit as well as potential damage to humans. Workers exposed to polyacrylate coatings have pleural effusion, pericardial effusion, and pulmonary fibrosis and granuloma, which are thought to be related to the high exposure to nanomaterials in the coatings. The study aimed to determine whether polyacrylate/silica nanoparticles cause similar toxicity in rats, as observed in exposed workers. Ninety male Wistar rats were randomly divided into five groups with 18 rats in each group. The groups included the saline control group, another control group of polyacrylate only, and low-, intermediate-, and high-dose groups of polyacrylate/nanosilica with concentrations of 3.125, 6.25, and 12.5 mg/kg. Seventy-five rats for the 1-week study were terminated for scheduled necropsy at 24 hours, 3 days, and 7 days postintratracheal instillation. The remaining 15 rats (three males/group) had repeated ultrasound and chest computed tomography examinations in a 2-week study to observe the pleural and pericardial effusion and pulmonary toxicity. We found that polyacrylate/nanosilica resulted in pleural and pericardial effusions, where nanosilica was isolated and detected. Effusion occurred on day 3 and day 5 post-administration of nanocomposites in the 6.25 and 12.5 mg/kg groups, it gradually rose to a maximum on days 7-10 and then slowly decreased and disappeared on day 14. With an increase in polyacrylate/nanosilica concentrations, pleural effusion increased, as shown by ultrasonographic qualitative observations. Pulmonary fibrosis and granuloma were also observed in the high-dose polyacrylate/nanosilica group. Our study shows that polyacrylate/nanosilica results in specific toxicity presenting as pleural and pericardial effusion, as well as pulmonary fibrosis and granuloma, which are almost identical to results in reported patients. These results indicate the urgent need and importance of nanosafety and awareness of toxicity of polyacrylate/nanosilica.

Longitudinal Measurement of Pleural Fluid Biochemistry and Cytokines in Malignant Pleural Effusions

BACKGROUND

Malignant pleural effusion (MPE) is common. Existing literature on pleural fluid compositions is restricted to cross-sectional sampling with little information on longitudinal changes of fluid biochemistry and cytokines with disease progression. Indwelling pleural catheters provide the unique opportunity for repeated sampling and longitudinal evaluation of MPE, which may provide insight into tumor pathobiology.

METHODS

We collected 638 MPE samples from 103 patients managed with indwelling pleural catheters over 95 days (median, range 0-735 days) and analyzed them for protein, pH, lactate dehydrogenase, and glucose levels. Peripheral blood was quantified for hematocrit, platelets, leukocytes, protein, and albumin. Cytokine levels (monocyte chemotactic protein [MCP]-1; vascular endothelial growth factor; interleukin-6, -8, and -10; tumor necrosis factor-α; and interferon-gamma) were determined in 298 samples from 35 patients with mesothelioma. Longitudinal changes of all parameters were analyzed using a linear mixed model.

RESULTS

Significant decreases were observed over time in pleural fluid protein by 8 g/L per 100 days (SE, 1.32; P < .0001) and pH (0.04/100 days; SE, 0.02; P = .0203), accompanied by a nonsignificant rise in lactate dehydrogenase. The ratio of pleural fluid to serum protein decreased by 0.06/100 days (SE, 0.02; P = .04). MPEs from mesothelioma (n = 63) had lower pleural fluid glucose (P = .0104) at baseline and a faster rate of decline in glucose (P = .0423) when compared with non-mesothelioma effusions (n = 38). A progressive rise in mesothelioma pleural fluid concentration of [log] MCP-1 ([log] 0.37 pg/mL per 100 days; SE, 0.13; P = .0046), but not of other cytokines, was observed.

CONCLUSIONS

MPE fluids become less exudative and more acidic over the disease course. The rise in MCP-1 levels suggests a pathobiological role in MPE.

Retained Blood Syndrome after Cardiac Surgery: A New Look at an Old Problem

Retained blood occurs when drainage systems fail to adequately evacuate blood during recovery from cardiothoracic surgery. As a result, a spectrum of mechanical and inflammatory complications can ensue in the acute, subacute, and chronic setting. The objectives of this review were to define the clinical syndrome associated with retained blood over the spectrum of recovery and to review existing literature regarding how this may lead to complications and contributes to poor outcomes. To better understand and prevent this constellation of clinical complications, a literature review was conducted, which led us to create a new label that better defines the clinical entity we have titled retained blood syndrome. Analysis of published reports revealed that 13.8% to 22.7% of cardiac surgical patients develop one or more components of retained blood syndrome. This can present in the acute, subacute, or chronic setting, with different pathophysiologic mechanisms active at different times. The development of retained blood syndrome has been linked to other clinical outcomes, including the development of postoperative atrial fibrillation and infection and the need for hospital readmission. Grouping multiple objectively measurable and potentially preventable postoperative complications that share a common etiology of retained blood over the continuum of recovery demonstrates a high prevalence of retained blood syndrome. This suggests the need to develop, implement, and test clinical strategies to enhance surgical drainage and reduce postoperative complications in patients undergoing cardiothoracic surgery.

VEGF correlates with inflammation and fibrosis in tuberculous pleural effusion

Objective. To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in tuberculous pleural effusion (TBPE) and their clinical importance. Methods. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores and effusion vascular endothelial growth factor (VEGF), interleukin- (IL-) 8, plasminogen activator inhibitor type-1 (PAI-1), and tissue type plasminogen activator (tPA) were measured. Treatment outcome and pleural fibrosis, defined as radiological residual pleural thickening (RPT), were assessed at 6-month follow-up. Results. The effusion size and effusion lactate dehydrogenase (LDH), VEGF, IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher, while effusion glucose, pH value, and tPA were significantly lower, in loculated than in nonloculated TBPE. VEGF and IL-8 correlated positively with LDH and PAI-1/tPA ratio and negatively with tPA in both loculated and nonloculated TBPE. Patients with higher VEGF or greater effusion size were prone to develop RPT (n = 14; VEGF, odds ratio 1.28, P = 0.01; effusion size, odds ratio 1.01, P = 0.02), and VEGF was an independent predictor of RPT in TBPE (receiver operating characteristic curve AUC = 0.985, P < 0.001). Conclusions. Effusion VEGF correlates with pleural inflammation and fibrosis and may be targeted for adjunct therapy for TBPE.

Management of malignant pleural effusions: questions that need answers

PURPOSE OF REVIEW

Malignant pleural effusion (MPE) is common. However, regardless of the differences between patients, their underlying cancer type, and pleural fluid characteristics, management options are often limited. These have not advanced significantly over the last 80 years since pleurodesis was first described. Correspondingly, patient-related outcome measures have been neglected. The evidence (or lack of) behind the current treatment recommendations is reviewed and key research questions are described.

RECENT FINDINGS

Talc continues to be the most effective sclerosant available for pleurodesis in MPE. A recent randomized controlled trial comparing talc pleurodesis and indwelling pleural catheter insertion as first-line therapy suggests these approaches are equally effective, and utilized a patient-based symptom score as the primary outcome. The need to acknowledge the advances in translational medicine and oncological therapies to measure patient-related trial outcomes and to target pleural fluid formation in MPE is discussed.

SUMMARY

Pulmonologists should be aware of the staggering lack of progress in the evidence that supports the current 'recommended' management of MPE. The need for a re-think about MPE management with a focus on alternative therapeutic targets and treatment objectives should be appreciated, in order to optimize future patient care.

Up-regulation of pro-angiogenic factors and establishment of tolerance in malignant pleural effusions

INTRODUCTION

Malignant pleural effusions (MPEs) are a significant source of cancer morbidity and mortality. Currently there is no cure for MPEs and treatments only palliate the symptoms. The purpose of this study was to determine if there are differences in markers of angiogenesis and immune phenotypes between adenocarcinoma-induced MPEs and benign pleural effusions (BPEs).

METHODS

Pleural effusions were collected from patients with MPEs and BPEs. Cells were isolated from effusions and characterized using fluorescent cell sorting (FACS). Pleural effusions were evaluated by ELISA for VEGF-A. An angiogenesis protein array was completed to compare protein expression in malignant and non-malignant effusions.

RESULTS

FACS analysis demonstrated lower accumulation of cytotoxic T-cells and significantly higher accumulation of monocytes, dendritic cells, mesothelial and tumor cells in MPEs compared to benign pleural effusions. MPEs were found to have 77-fold higher VEGF-A levels compared to BPEs. The angiogenesis protein array demonstrated elevated levels of pro-angiogenic factors VEGF-A, CXCL4 and MMP-8, and low levels of pro-inflammatory cytokines IL-8, MCP-1, and TGF-β1 in MPEs.

CONCLUSIONS

MPE is biased toward a Th2 dominant state. There is an increase in expression of VEGF-A and other pro-angiogenic factors in MPE. These data suggest there is a role for anti-angiogenesis therapy in patients with MPEs.

The role of vascular endothelial growth factor in the pathogenesis, diagnosis and treatment of malignant pleural effusion

Malignant pleural effusions (MPEs) are a significant source of cancer-related morbidity. Over 150,000 patients in the United States suffer from breathlessness and diminished quality of life due to MPE each year. Current management strategies are of mostly palliative value and focus on symptom control; they do not address the pathobiology of the effusion, nor do they improve survival. Further elucidation of the pathophysiological mechanisms, coupled with the development of novel treatments such as intrapleural chemotherapeutics targeting this process, has the potential to greatly improve the efficacy of our current management options. Vascular endothelial growth factor-A (VEGF-A) has been implicated as a critical cytokine in the formation of malignant pleural effusions. Elevated levels of VEGF produced by tumor cells, mesothelial cells, and infiltrating immune cells result in increased vascular permeability, cancer cell transmigration, and angiogenesis. Therefore antiangiogenic therapies such as Bevacizumab, a monoclonal antibody targeting VEGF-A, may have a potential role in the management of malignant pleural effusions. Herein we review the pathogenesis and potential treatment strategies of malignant pleural effusions, with a focus on angiogenesis and antiangiogenic therapeutics.

Treatment of malignant effusion by oncolytic virotherapy in an experimental subcutaneous xenograft model of lung cancer

Background

Malignant pleural effusion (MPE) is associated with advanced stages of lung cancer and is mainly dependent on invasion of the pleura and expression of vascular endothelial growth factor (VEGF) by cancer cells. As MPE indicates an incurable disease with limited palliative treatment options and poor outcome, there is an urgent need for new and efficient treatment options.

Methods

In this study, we used subcutaneously generated PC14PE6 lung adenocarcinoma xenografts in athymic mice that developed subcutaneous malignant effusions (ME) which mimic pleural effusions of the orthotopic model. Using this approach monitoring of therapeutic intervention was facilitated by direct observation of subcutaneous ME formation without the need of sacrificing mice or special imaging equipment as in case of MPE. Further, we tested oncolytic virotherapy using Vaccinia virus as a novel treatment modality against ME in this subcutaneous PC14PE6 xenograft model of advanced lung adenocarcinoma.

Results

We demonstrated significant therapeutic efficacy of Vaccinia virus treatment of both advanced lung adenocarcinoma and tumor-associated ME. We attribute the efficacy to the virus-mediated reduction of tumor cell-derived VEGF levels in tumors, decreased invasion of tumor cells into the peritumoral tissue, and to viral infection of the blood vessel-invading tumor cells. Moreover, we showed that the use of oncolytic Vaccinia virus encoding for a single-chain antibody (scAb) against VEGF (GLAF-1) significantly enhanced mono-therapy of oncolytic treatment.

Conclusions

Here, we demonstrate for the first time that oncolytic virotherapy using tumor-specific Vaccinia virus represents a novel and promising treatment modality for therapy of ME associated with advanced lung cancer.

Intrapleural combination therapy with bevacizumab and cisplatin for non-small cell lung cancer‑mediated malignant pleural effusion

Malignant pleural effusion (MPE) is a common complication of advanced non-small cell lung cancer (NSCLC). Bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor (VEGF), has been shown to be efficient in suppressing the accumulation of pleural fluid. However, whether intrapleural delivery of bevacizumab can be used to treat MPE remains unknown. The aim of the present study was to evaluate the efficacy and safety of combined intrapleural therapy with bevacizumab and cisplatin, an antineoplastic agent, in controlling MPE. A total of 72 NSCLC study subjects with MPE were randomly assigned to one of two groups. The first group received intrapleural bevacizumab (300 mg) with cisplatin (30 mg) therapy and the second group received intrapleural cisplatin (30 mg) therapy alone. Pleural fluid was collected from both groups prior to and following treatment. The levels of VEGF and carcinoembryonic antigen (CEA) in the pleural fluid were determined by ELISA. In 70 evaluable study subjects, the curative efficacy in the bevacizumab group was significantly higher than that found in the cisplatin group (83.33 vs. 50.00%, respectively; p<0.05). Therapy with combined bevacizumab plus cisplatin significantly reduced VEGF levels in the pleural fluid (p<0.01). In the bevacizumab group, the levels of VEGF in the pleural fluid were significantly lower compared to those of the cisplatin group after treatment, which showed greater efficacy (p<0.01). In addition, combination therapy showed greater efficacy in the patients with high levels of VEGF expression (p<0.01). There was no significant difference in grade III/IV adverse events between the two groups. All procedures were well tolerated by the patients. Combined intrapleural therapy with bevacizumab and cisplatin was effective and safe in managing NSCLC-mediated MPE. We propose that VEGF expression levels in MPE could serve as a prognostic marker for bevacizumab therapy.

An unusual cause of massive pleural effusion

Pleural effusions in ovarian hyperstimulation syndrome, whether transudative or exudative, can occur in up to 30% of cases. This disorder is always reversible but may have various clinical presentations and degrees of severity. Although assessing for risk factors to predict clinical severity is helpful, it is rare for ovarian hyperstimulation syndrome to present as a massive pleural effusion requiring emergent intervention. In this study, such a case is reported.

Phase II study of bevacizumab in patients with HIV-associated Kaposi's sarcoma receiving antiretroviral therapy

PURPOSE

Alternatives to cytotoxic agents are desirable for patients with HIV-associated Kaposi's sarcoma (KS). Vascular endothelial growth factor-A (VEGF-A) contributes to KS pathogenesis. We evaluated the humanized anti-VEGF-A monoclonal antibody, bevacizumab, in patients with HIV-KS.

PATIENTS AND METHODS

Patients with HIV-KS who either experienced progression while receiving highly active antiretroviral therapy (HAART) for at least 1 month or did not regress despite HAART for at least 4 months were administered bevacizumab 15 mg/kg intravenously on days 1 and 8 and then every 3 weeks. The primary objective was assessment of antitumor activity using modified AIDS Clinical Trial Group (ACTG) criteria for HIV-KS. HIV-uninfected patients were also eligible and observed separately.

RESULTS

Seventeen HIV-infected patients were enrolled. Fourteen patients had been receiving effective HAART for at least 6 months (median, 1 year). Thirteen patients had advanced disease (ACTG T(1)), 13 patients had received prior chemotherapy for KS, and seven patients had CD4 count less than 200 cells/μL. Median number of cycles was 10 (range, 1 to 37 cycles); median follow-up was 8.3 months (range, 3 to 36 months). Of 16 assessable patients, best tumor responses observed were complete response (CR) in three patients (19%), partial response (PR) in two patients (12%), stable disease in nine patients (56%), and progressive disease in two patients (12%). Overall response rate (CR + PR) was 31% (95% CI, 11% to 58.7%). Four of five responders had received prior chemotherapy for KS. Over 202 cycles, grade 3 to 4 adverse events at least possibly attributed to therapy included hypertension (n = 7), neutropenia (n = 5), cellulitis (n = 3), and headache (n = 2).

CONCLUSION

Bevacizumab is tolerated in patients with HIV-KS and has activity in a subset of patients.

Management of infectious processes of the pleural space: a review

Pleural effusions can present in 40% of patients with pneumonia. Presence of an effusion can complicate the diagnosis as well as the management of infection in lungs and pleural space. There has been an increase in the morbidity and mortality associated with parapneumonic effusions and empyema. This calls for employment of advanced treatment modalities and development of a standardized protocol to manage pleural sepsis early. There has been an increased understanding about the indications and appropriate usage of procedural options at clinicians' disposal.

Blockage of vascular endothelial growth factor (VEGF) reduces experimental pleurodesis

BACKGROUND AND OBJECTIVE

Chemical pleurodesis controls recurrent malignant pleural effusion. The mechanism that determines pleural symphysis involves the action of vascular endothelial growth factor (VEGF). We assessed the influence of the anti-VEGF antibody (bevacizumab) on pleurodesis induced by talc or silver nitrate and analyzed the temporal development of pleural angiogenesis.

METHODS

Sixty New Zealand rabbits received intrapleural injection (2mL) of talc (400mg/kg) or 0.5% silver nitrate. In each group, half of the animals received an intravenous injection of bevacizumab 30min before the sclerosing agent. Five animals from each group were euthanized 7, 14, or 28 days after the procedure. Adhesions and inflammation (scores: 0-4), thickness (μm), vascular density (vessels/field), and collagen fibers (μm(2)) were evaluated in the visceral pleura.

RESULTS

Antibody anti-VEGF interferes in pleurodesis induced by talc or silver nitrate. Pleural inflammation was discreet with no difference between the groups, regardless the anti-VEGF treatment. Concerning the vascular density of the visceral pleura, a smaller number of neoformed vessels was noted in the animals that received bevacizumab. In the animals receiving silver nitrate, the decrement in adhesions and vascular density was associated with reduced thick and thin collagen fibers, resulting in less pleural thickness.

CONCLUSION

The anti-VEGF antibody inhibits adhesions between pleural layers. Despite being an experimental study in animals with normal pleura, the results call attention to a likely lack of success in pleurodesis when VEGF blockers are used.

A sulindac analogue is effective against malignant pleural effusion in mice

OBJECTIVES

To examine whether a sulindac derivative (C-18) with previously reported anti-angiogenic properties limits malignant pleural effusion (MPE) formation in mice.

METHODS

MPE was generated by intrapleural injection of murine adenocarcinoma cells in C57BL/6 mice. Animals were divided into three groups, a control group and two treatment groups receiving intraperitoneally a daily dose of either 1 mg or 2 mg of C-18 for a total of 12 doses. Mice were sacrificed on day 14.

MEASUREMENTS AND MAIN RESULTS

Pleural fluid volume and the number of pleural tumor implantations were measured. Tumor angiogenesis, pleural vascular permeability and the host inflammatory response were also assessed. C-18 significantly limited pleural fluid formation and inhibited intrapleural tumor dissemination. The mean±SEM pleural fluid volume was 758±63 μl for the control group, compared to 492±120 μl (p=0.042) and 279±77 μl (p<0.001) for the low dose and high dose group of C-18, respectively. Control group animals had 6.2±1 intrapleural tumors, while C-18 treated animals had 3.1±0.8 (p=0.014) and 3±0.7 (p=0.009) for the low and high dose respectively. In addition C-18 significantly suppressed pleural vascular permeability. No significant difference in tumor angiogenesis and inflammatory response was observed, while there was also no measurable effect in tumor cell apoptosis and proliferation in vitro and in vivo.

CONCLUSIONS

C-18 halted experimental MPE formation and intrapleural tumor dissemination, through down-regulation of pleural vascular permeability.