Malignant pleural mesothelioma: a comprehensive review

Epithelial Malignant Pleural Mesothelioma Mimics Lymphoma on 18 F-FDG PET/MRI : A Case Report

ABSTRACT

Malignant pleural mesothelioma is a rare tumor with a poor prognosis. We describe a case of 55-year-old man without asbestos exposure history presenting with extensive lymph nodes with high 18 F-FDG uptake in PET/MRI but atypical pleural manifestations thereby being misdiagnosed for lymphoma. Pathological examination concludes for an epithelioid mesothelioma-associated lymph node metastasis. This case emphasizes that with the extensive lymph node abnormalities shown in PET imaging, in addition to the general consideration of lymphoma, it is still necessary to be vigilant about the possibility of mesothelioma and emphasizes the necessity of pathological examination.

Complex Genomic Rearrangement Patterns in Malignant Pleural Mesothelioma due to Environmental Asbestos Exposure

Malignant pleural mesothelioma (MPM) is a rare type of cancer, and its main risk factor is exposure to asbestos. Accordingly, our knowledge of the genomic structure of an MPM tumor is limited when compared to other cancers. In this study, we aimed to characterize complex genomic rearrangement patterns and variations to better understand the genomics of MPM tumors. We comparatively scanned 3 MPM tumor genomes by Whole-Genome Sequencing and High-Resolution SNP array. We also used various computational algorithms to detect both CNAs and complex chromosomal rearrangements. Genomic data obtained from each bioinformatics tool are interpreted comparatively to better understand CNAs and cancer-related Nucleotide variations in MPM tumors. In patients 1 and 2, we found pathogenic nucleotide variants of BAP1, RB1, and TP53. These two MPM genomes exhibited a highly rearranged chromosomal rearrangement pattern resembling Chromomanagesis particularly in the form of Chromoanasynthesis. In patient 3, we found nucleotide variants of important cancer-related genes, including TGFBR1, KMT2C, and PALLD, to have lower chromosomal rearrangement complexity compared with patients 1 and 2. We also detected several actionable nucleotide variants including XRCC1, ERCC2. We also discovered the SKA3-DDX10 fusion in two MPM genomes, which is a novel finding for MPM. We found that MPM genomes are very complex, suggesting that this highly rearranged pattern is strongly related to driver mutational status like BAP1, TP53 and RB1.

A biomarker predicting unfavorable prognosis in malignant pleural mesothelioma: systemic immune–inflammation index

Aim: Malignant pleural mesothelioma (MPM) is an extremely mortal condition. Only a few prognostic biomarkers have been described for MPM. Our study looked into the association between patient survival and the Systemic Immune Inflammation Index (SII). Material and Method: A total of 158 patients who were admitted to our hospital between January 2013 and December 2022, and had a histopathologically confirmed diagnosis of MPM were included in the study. Before treatment, hematological parameters and SII were determined. A Spearman's correlation analysis was performed to analyze the correlation of mean survival with hematological parameters. Results: The study involved 158 patients in all. 70 patients had a history of smoking, the median age was 63 years, the mean survival time was 15.3 months, and 57.6% of the participants were men. The epithelioid type (84.2%) was the most prevalent histological subtype, and 29 patients had stage 4 illnesses. Of the participants, 84% had received chemotherapy, and 22% had received radiotherapy before. Among the 39 patients who had surgery, 5 had an extrapleural pneumonectomy. SII mean±sd was (1427.2±1207.3). The patients with stage 4 disease had significantly shorter survival (p=0.001). The patients who had surgery survived significantly longer (p=0.01). Hemoglobin (Hb) (r:0.21, p:0.01) and Hematocrit (Hct) (r:0.18, p:0.03) values showed weak positive correlations with mean survival. It was evident that mean survival got shorter as SII (r:-0.17, p:0.04) and neutrophil-lymphocyte ratio (NLR) (r:-0.19, p:0.02) values got higher. On the other hand, there was a strong positive association between mean survival and the lymphocyte-monocyte ratio (LMR) (r:0.21, p:0.01). When the parameters that had statistically significant differences among the groups were taken as control variables and the statistical analysis was re-performed, it was found that Hgb and Hct values as well as NLR and LMR ratios lost their significant correlations with survival. However, the SII ratio was still negatively correlated with survival (r:-0.16, p:0.04). Conclusion: Pretreatment SII is a noninvasive and easy-to-calculate biomarker that predicts the prognosis of MPM. It is negatively correlated with mean survival regardless of the tumor stage and surgical management.

Evaluation of Detector Position and Light Fluence Distribution Using an Infrared Navigation System during Pleural Photodynamic Therapy†

Photodynamic therapy (PDT) has been used to treat malignant pleural mesothelioma. Current practice involves delivering light to a prescribed light fluence with a point source, monitored by eight isotropic detectors inside the pleural cavity. An infrared (IR) navigation system was used to track the location of the point source throughout the treatment. The recorded data were used to reconstruct the pleural cavity and calculate the light fluence to the whole cavity. An automatic algorithm was developed recently to calculate the detector positions based on recorded data within an hour. This algorithm was applied to patient case studies and the calculated results were compared to the measured positions, with an average difference of 2.5 cm. Calculated light fluence at calculated positions were compared to measured values. The differences between the calculated and measured light fluence were within 14% for all cases, with a fixed scattering constant and a dual correction method. Fluence-surface histogram (FSH) was calculated for photofrin-mediated PDT to be able to cover 80% of pleural surface area to 50 J cm-2 (83.3% of 60 J cm-2 ). The study demonstrates that it will be possible to eliminate the manual measurement of the detector positions, reducing the patient's time under anesthesia.

The cytologic diagnosis of mesothelioma: are we there yet?

INTRODUCTION

Mesothelioma is a rare but highly aggressive malignancy with poor prognosis that frequently present with recurrent effusions. Establishing the diagnosis by cytology can lead to early diagnosis and treatment and consequently improve prognosis.

MATERIALS AND METHODS

This review examines the cytological diagnosis of mesothelioma in the context of its historical and morphologic evolution and provides an update of the current reporting systems. Clues to identify the mesothelial and malignant nature of the sample are detailed as well as the supporting ancillary tests.

RESULTS

Cytologically, the samples are overwhelmingly cellular and malignancy is recognized by both architectural and cytological atypia. Numerous variably sized clusters and enlarged cells are easily identified, some with papillary architecture and collagen cores. Recognizing the mesothelial nature of the cells and supportive immunostains are essential to rule out the differential diagnosis of metastatic carcinomas and reactive mesothelium. Current ancillary tests such as homozygous deletion of CDKN2A, loss of BRCA1-associated protein, and methylthioadenosine phosphorylase expression can provide further support of malignancy.

CONCLUSIONS

At this time with the aid of current ancillary tests and in the hands of cytopathologists with adequate experience with the interpretation of effusions, the diagnosis of mesothelioma can be established with accuracy in most cases.

Define the Two Molecular Subtypes of Epithelioid Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a fatal disease of respiratory system. Despite the availability of invasive biomarkers with promising results, there are still significant diagnostic and therapeutic challenges in the treatment of MPM. One of three main mesothelioma cell types, epithelioid mesothelioma makes up approximately 70% of all mesothelioma cases. Different observational findings are under process, but the molecular heterogeneity and pathogenesis of epithelioid malignant pleural mesothelioma (eMPM) are still not well understood. Through molecular analysis, expression profiling data were used to determine the possibility and optimal number of eMPM molecular subtypes. Next, clinicopathological characteristics and different molecular pathways of each subtype were analyzed to prospect the clinical applications and advanced mechanisms of eMPM. In this study, we identified two distinct epithelioid malignant pleural mesothelioma subtypes with distinct gene expression patterns. Subtype I eMPMs were involved in steroid hormone biosynthesis, porphyrin and chlorophyll metabolism, and drug metabolism, while subtype II eMPMs were involved in rational metabolism, tyrosine metabolism, and chemical carcinogenesis pathways. Additionally, we identified potential subtype-specific therapeutic targets, including CCNE1, EPHA3, RNF43, ROS1, and RSPO2 for subtype I and CDKN2A and RET for subtype II. Considering the need for potent diagnostic and therapeutic biomarkers for eMPM, we are anticipating that our findings will help both in exploring underlying mechanisms in the development of eMPM and in designing targeted therapy for eMPM.

Systematic Review, Meta-Analysis and Bioinformatic Analysis of Biomarkers for Prognosis of Malignant Pleural Mesothelioma

In previous studies, non-invasive diagnostic biomarkers showed great benefit in the early-stage diagnosis of malignant pleural mesothelioma (MPM). However, the accuracy of different biomarkers was controversial. In this study, meta-analysis and bioinformatics analysis were conducted to compare the accuracy of the following three biomarkers and explore the relationship between the gene expression levels and MPM. A systematic search of meta-analysis was conducted using PubMed, EMBASE and Cochrane Library to identify relevant studies from the inception to March 2021. QUADAS-2 for Quality Assessment of Diagnostic Accuracy Studies was used to evaluate the quality of eligible studies. The meta-analysis was performed utilizing Stata 15.0 and Review Manager 5.4 software. The meta-analysis results showed that 31 studies that involved 8750 participants were included. The pooled sensitivity and specificity (SPE) were 0.90 (95% CI: 0.74, 0.97) and 0.91 (95% CI: 0.84, 0.95) for Fibulin-3, 0.66 (95% CI, 0.51–0.78) and 0.91 (95% CI, 0.82–0.96) for mesothelin (MSLN), 0.68 (95% CI: 0.63,0.73) and 0.86 (95% CI: 0.82,0.90) for soluble mesothelin-related peptides (SMRP), and 0.74 (95% CI, 0.66-0.80) and 0.89 (95% CI, 0.85–0.91) for MSLN + SMRP + Fibulin-3. Compared with the other two biomarkers, Fibulin-3 may be more appropriate to be one of the indicators for combined diagnosis. Bioinformatics analysis showed that the low expression level of the MSLN gene was significantly related to longer survival time and better prognosis of MPM patients. However, considering the limitation in the quality and sample size of the included research, further studies are required.

A Role for PET/CT in response assessment of malignant pleural mesothelioma

Malignant pleural mesothelioma is a rare type of cancer, whose incidence, however, is increasing and will presumably continue to rise in the coming years. Key features of this disease comprise its mantle-shaped, pleura-associated, often multifocal growth, which cause diagnostic challenges. A growing number of mesotheliomas are being treated with novel immunotherapies for which no image derived general response criteria have been established. However, recent studies indicate that FDG-PET/CT could be superior for response assessment compared to CT-based criteria. This article aims at providing an overview of response assessment criteria dedicated to malignant pleural mesothelioma, such as mRECIST, iRECIST, and PERCIST. In addition, the potential future role of PET/CT in the management of malignant pleural mesothelioma will also be discussed.

Prognostic Bone Metastasis-Associated Immune-Related Genes Regulated by Transcription Factors in Mesothelioma

Mesothelioma (MESO) is a mesothelial originate neoplasm with high morbidity and mortality. Despite advancement in technology, early diagnosis still lacks effectivity and is full of pitfalls. Approaches of cancer diagnosis and therapy utilizing immune biomarkers and transcription factors (TFs) have attracted more and more attention. But the molecular mechanism of these features in MESO bone metastasis has not been thoroughly studied. Utilizing high-throughput genome sequencing data and lists of specific gene subsets, we performed several data mining algorithm. Single-sample Gene Set Enrichment Analysis (ssGSEA) was applied to identify downstream immune cells. Potential pathways involved in MESO bone metastasis were identified using Gene Oncology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Gene Set Variation Analysis (GSVA), Gene Set Enrichment Analysis (GSEA), and Cox regression analysis. Ultimately, a model to help early diagnosis and to predict prognosis was constructed based on differentially expressed immune-related genes between bone metastatic and nonmetastatic MESO groups. In conclusion, immune-related gene SDC2, regulated by TFs TCF7L1 and POLR3D, had an important role on immune cell function and infiltration, providing novel biomarkers and therapeutic targets for metastatic MESO.

CircPLK1 Acts as a Carcinogenic Driver to Promote the Development of Malignant Pleural Mesothelioma by Governing the miR-1294/HMGA1 Pathway

The deregulation of circular RNAs (circRNAs) is involved in cancer development. CircRNA polo-like kinase 1 (circPLK1) was reported to promote breast cancer development. However, the role of circPLK1 in malignant pleural mesothelioma (MPM) is unclear. The expression of circPLK1, miR-1294, and high mobility group AT-hook 1 (HMGA1) mRNA was measured by quantitative real-time PCR (qPCR). Cell viability was detected by CCK-8 assay. Colony formation ability was monitored by colony formation assay. Cell proliferation was detected by EdU assay. Cell migration and cell invasion were monitored by transwell assay. Cancer cell stemness was investigated by sphere formation assay. The protein levels of marker proteins and HMGA1 expression were measured by western blot analysis. The binding relationship between miR-1294 and circPLK1 or HMGA1 was validated by pull-down assay, dual-luciferase reporter assay or RIP assy. Animal study was performed to disclose the role of circPLK1 in vivo. Exosomes were identified by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). CircPLK1 was upregulated in MPM tumor tissues and cell lines. CircPLK1 knockdown suppressed the proliferation, migration, invasion and stemness of MPM cells. CircPLK1 contained a binding site for miR-1294 and thus bound to miR-1294 to sequester its expression. Inhibition of miR-1294 reversed the effects of circPLK1 knockdown. HMGA1 was a target of miR-1294, and circPLK1 bound to miR-1294 to increase the expression of HMGA1. MiR-1294 restoration also suppressed the proliferation, migration, invasion and stemness of MPM cells, while these effects were abolished by HMGA1 overexpression. In addition, circPLK1 knockdown inhibited tumor growth in vivo. CircPLK1 was overexpressed in exosomes derived from serum of MPM patients. CircPLK1 knockdown inhibited MPM cell proliferation, migration, invasion and stemness by targeting the miR-1294/HMGA1 pathway.

Malignant pleural mesothelioma: an update

Malignant mesotheliomas are rare types of cancers that affect the mesothelial surfaces, usually the pleura and peritoneum. They are associated with asbestos exposure, but due to a latency period of more than 30 years and difficult diagnosis, most cases are not detected until they reach advanced stages. Treatment options for this tumor type are very limited and survival ranges from 12 to 36 months. This review discusses the molecular physiopathology, current diagnosis, and latest therapeutic options for this disease.

A Rare Case of Malignant Pleural Mesothelioma in a Young Healthy Male Without Asbestos Exposure

Malignant pleural mesothelioma (MPM) is a highly aggressive malignant tumor that arises from mesothelial cells of pleural cavity. The main risk factor for MPM is asbestos exposure with most cases discovered in elderly males after a long latency period. However, here we report a rare case of MPM diagnosed in a healthy young male patient without significant asbestos exposure.

We report the case of an otherwise healthy 47-year-old male who presented with one week of exertional dyspnea and chest pain. Chest X-ray showed unilateral large pleural effusion. Chest CT scan revealed confluent right hilar mass and pleural thickening. Pleural fluid analysis showed exudative features. Cytology was negative for malignant cells. Core tissue biopsy showed features of epithelioid mesothelioma.

Although most cases of MPM have been reported in elderly male patients with significant asbestos exposure, more research is needed to explain the pathogenesis of MPM in young patients without asbestos exposure.

Inhibition of cyclin-dependent kinase 7 down-regulates yes-associated protein expression in mesothelioma cells

Cyclin-dependent kinase 7 (CDK7) is a protein kinase that plays a major role in transcription initiation. Yes-associated protein (YAP) is a main effector of the Hippo/YAP signalling pathway. Here, we investigated the role of CDK7 on YAP regulation in human malignant pleural mesothelioma (MPM). We found that in microarray samples of human MPM tissue, immunohistochemistry staining showed correlation between the expression level of CDK7 and YAP (n = 70, r = .513). In MPM cells, CDK7 expression level was significantly correlated with GTIIC reporter activity (r = .886, P = .019). Inhibition of CDK7 by siRNA decreased the YAP protein level and the GTIIC reporter activity in the MPM cell lines 211H, H290 and H2052. Degradation of the YAP protein was accelerated after CDK7 knockdown in 211H, H290 and H2052 cells. Inhibition of CDK7 reduced tumour cell migration and invasion, as well as tumorsphere formation ability. Restoration of the CDK7 gene rescued the YAP protein level and GTIIC reporter activity after siRNA knockdown in 211H and H2052 cells. Finally, we performed a co-immunoprecipitation analysis using an anti-YAP antibody and captured the CDK7 protein in 211H cells. Our results suggest that CDK7 inhibition reduces the YAP protein level by promoting its degradation and suppresses the migration and invasion of MPM cells. Cyclin-dependent kinase 7 may be a promising therapeutic target for MPM.

Scientific Advances and New Frontiers in Mesothelioma Therapeutics

Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer that arises from the mesothelial surface of the pleural and peritoneal cavities, the pericardium, and rarely, the tunica vaginalis. The incidence of MPM is expected to increase worldwide in the next two decades. However, even with the use of multimodality treatment, MPM remains challenging to treat, with a 5-year survival rate of less than 5%. The International Association for the Study of Lung Cancer has gathered experts in different areas of mesothelioma research and management to summarize the most significant scientific advances and new frontiers related to mesothelioma therapeutics.

Building a Bridge between Chemotherapy and Immunotherapy in Malignant Pleural Mesothelioma: Investigating the Effect of Chemotherapy on Immune Checkpoint Expression

In light of the promising results of immune checkpoint blockade (ICPB) in malignant pleural mesothelioma (MPM), we investigated the effect of different chemotherapeutic agents on the expression of immune checkpoints (ICPs) in order to rationally design a good treatment schedule for their combination with ICP blocking antibodies. Cisplatin, oxaliplatin and pemetrexed are interesting chemotherapeutic agents to combine with immunotherapy given their immunomodulatory capacities. We looked into cisplatin and pemetrexed because their combination is used as first-line treatment of MPM. Additionally, the effect of the immunogenic chemotherapeutic agent, oxaliplatin, was also studied. Three different MPM cell lines were used for representation of both epithelioid and sarcomatoid subtypes. The desired inhibitory concentrations of the chemotherapeutic agents were determined with the SRB-assay. Allogeneic co-cultures of MPM cells with healthy donor peripheral blood mononuclear cells (PBMC) were set up to assess the effect of these chemotherapeutic agents on the expression of ICPs (PD-1, LAG-3, TIM-3) and their ligands (PD-L1, PD-L2, galectin-9). Cisplatin might be a promising treatment to combine with ICP blocking antibodies since our MPM cell lines were most susceptible to this stand-alone treatment. We found that the expression of ICPs and their ligands on both MPM cells and PBMC was mostly downregulated or unaltered when treated with chemotherapeutic agents, though no clear trend could be determined.

Mesothelin, Calretinin, and Megakaryocyte Potentiating Factor as Biomarkers of Malignant Pleural Mesothelioma

PURPOSE

Malignant pleural mesothelioma (MPM) is a highly lethal cancer caused by exposure to asbestos. Currently, the diagnosis is a challenge, carried out by means of invasive methods of limited sensitivity. This is a case-control study to evaluate the individual and combined performance of minimally invasive biomarkers for the diagnosis of MPM.

METHOD

A study of 166 incident cases of MPM and 378 population controls of Mestizo-Mexican ethnicity was conducted. Mesothelin, calretinin, and megakaryocyte potentiating factor (MPF) were quantified in plasma by ELISA. The samples were collected from 2011 to 2016.

RESULTS

Based on ROC analysis and a preset specificity of 95%, the combination of the three biomarkers reached an AUC of 0.944 and a sensitivity of 82% in men. In women, an AUC of 0.937 and a sensitivity of 87% were reached. In nonconditional logistic regression models, the adjusted ORs in men were 7.92 (95% CI 3.02-20.78) for mesothelin, 20.44 (95% CI 8.90-46.94) for calretinin, and 4.37 (95% CI 1.60-11.94) for MPF. The ORs for women were 28.89 (95% CI 7.32-113.99), 17.89 (95% CI 3.93-81.49), and 2.77 (95% CI 0.47-16.21), respectively.

CONCLUSIONS

To our knowledge, this is the first study evaluating a combination of mesothelin, calretinin, and MPF, and demonstrating a sex effect for calretinin. The biomarker panel showed a good performance in a Mestizo-Mexican population, with high sensitivity and specificity for the diagnosis of MPM.

Detection of circulating tumor cells with a novel microfluidic system in malignant pleural mesothelioma

Detection of rare tumor cells circulating in the blood (CTCs) presents technical challenges. CellSearch, the only approved system for clinical use, fails to capture epithelial cell adhesion molecule‐negative CTCs such as malignant pleural mesothelioma (MPM). We have developed a novel microfluidic device (CTC‐chip) in which any Ab to capture CTCs is conjugated. The CTC‐chip was coated with an Ab against podoplanin that is abundantly expressed on MPM. Circulating tumor cell‐detection performance was evaluated in experimental models in which MPM cells were spiked in blood sampled from a healthy volunteer and in clinical samples drawn from MPM patients. The CTC‐chip showed superior CTC‐detection performance over CellSearch in experimental models (sensitivity, 63.3%‐64.5% vs 0%‐1.1%; P < .001) and in clinical samples (CTC‐positivity, 68.8% vs 6.3%; P < .001). A receiver operating characteristic (ROC) analysis showed that the CTC test provided a significant diagnostic performance in discrimination of unresectable disease from resectable disease (area under the ROC curve, 0.851; P = .003). The higher CTC count (≥2 cells/mL) was significantly associated with a poor prognosis (P = .030). The novel CTC‐chip enabled sensitive detection of CTCs, which provided significant diagnostic and prognostic information in MPM.

Malignant mesothelioma presenting as recurrent hydro-pneumothorax: An atypical case presentation and literature review

Malignant Pleural Mesothelioma (MPM) is a rare pleural malignancy, with a vague presentation complicated by a decades-long latency period between environmental exposure and clinical manifestations. Spontaneous hydro-pneumothorax is a rare presentation of MPM, most often requiring invasive tissue biopsy to confirm the etiologic diagnosis. We present the case of 79-year-old male smoker with no documented history of asbestos exposure, who was found to have MPM after presenting with dyspnea and subsequently found to have recurrent hydro-pneumothorax. On Literature review of the limited documented cases of MPM with hydro-pneumothorax, we found an exclusively male population with a significant smoking history, a marked right sided pathology predominance, and a generally poor prognosis. While this corresponds with the examined case, and suggests that the presence of hydro-pneumothorax implies a high-grade tumor and significant tissue invasion, and therefore poor prognosis similar to that of stage 4 disease, it differs from more generalized case reviews of MPM, most importantly in their anatomical descriptions, prognostic indicators, and epidemiologic tendencies.

Ambient Asbestos Fiber Concentrations and Long-Term Trends in Pleural Mesothelioma Incidence between Urban and Rural Areas in the United States (1973-2012)

Over the past 40 years, measured ambient asbestos concentrations in the United States have been higher in urban versus rural areas. The purpose of this study was to determine whether variations in ambient asbestos concentrations have influenced pleural mesothelioma risk in females (who generally lacked historic occupational asbestos exposure relative to males). Male pleural mesothelioma incidence trends were analyzed to provide perspective for female trends. Annual age-adjusted incidence rates from 1973 to 2012 were obtained from the SEER 9, 13, and 18 databases for urban and rural locations, and standardized rate ratios were calculated. Female rural rates exceeded urban rates in almost half of the years analyzed, although the increases were not statistically significant, which is in line with expectations if there was no observable increased risk for urban locations. In contrast, male urban rates were elevated over rural rates for nearly all years examined and were statistically significantly elevated for 22 of the 40 years. Trend analyses demonstrated that trends for females remained relatively constant over time, whereas male urban and rural incidence increased into the 1980s and 1990s, followed by a decrease/leveling off. Annual female urban and rural incidence rates remained approximately five- to six-fold lower than male urban and rural incidence rates on average, consistent with the comparatively increased historical occupational asbestos exposure for males. The results suggest that differences in ambient asbestos concentrations, which have been reported to be 10-fold or greater across regions in the United States, have not influenced the risk of pleural mesothelioma.

Malignant pleural mesothelioma: A retrospective analysis of clinicopathological and survival data

BACKGROUND

  The aim of this study was to analyze the clinicopathological features of malignant pleural mesothelioma (MPM) and evaluate the therapeutic measures offered to patients with MPM and their impact on survival.

METHODS

  Data was retrospectively collected from the medical records of 304 patients who presented to the Department of Clinical Oncology and Nuclear Medicine, Ain Shams University between January 2003 and December 2008.

RESULTS

  The mean age of patients was 52.1 years (range 24-87 years). One hundred and ninety patients (62.5%) came from endemic areas and/or gave history of occupational asbestos exposure. One hundred and sixty-nine patients received chemotherapy. There was a significant difference between the median survival for patients who received chemotherapy (9 months, 95% CI 7.69-10.30) and those who were offered best supportive care (2 months, 95% CI 0.09-3.91). Other factors that affected the survival negatively were: non-epithelial pathology (P= 0.001); age >50 years (P= 0.012); bad performance status (P= 0.001); non-platinum based chemotherapy (P= 0.0001); and progressive disease (P= 0.000). Cox regression analysis revealed that the factors that predicted shorter survival were patients being offered best supportive care rather than chemotherapy and progressive disease.

CONCLUSION

  MPM is a growing health problem in Egypt that needs more attention. The current analysis of data reflects the importance of maintaining a high index of suspicion to allow for early diagnosis, especially for cases that live in areas with high asbestos exposure and for people who work in occupations that expose them to asbestos as well as their family members. Prospective randomized trials comparing multimodality approaches to other forms of treatment and including quality of life assessment are warranted.

Diagnostic value of fibulin-3 for malignant pleural mesothelioma: A systematic review and meta-analysis

Background

Several studies have investigated the diagnostic value of fibulin-3 for malignant pleural mesothelioma (MPM), but the results were various. Therefore, we performed a systematic review and meta-analysis to evaluate the diagnostic value of fibulin-3 for MPM.

Results

Eight studies were included in this work. The overall sensitivity of blood fibulin-3 were 0.87 (95% CI, 0.58 – 0.97) and 0.89 (95% CI, 0.77 – 0.95), respectively. The overall sensitivity and specificity of PF fibulin-3 for MPM were 0.73 (95% CI, 0.54 – 0.86) and 0.80 (95% CI, 0.60 – 0.91), respectively. The area under curve of blood and pleural effusion (PF) Fibulin-3 were 0.94 (95% CI, 0.91 – 0.96) 0.83 (95% CI, 0.79 – 0.86), respectively.

Methods

PubMed and EMBASE databases were searched up to July 29, 2016 to verify studies investigating the diagnostic value of fibulin-3 for MPM. The quality of eligible studies was assessed using the revised Quality Assessment for Studies of Diagnostic Accuracy tool (QUADAS-2). The overall sensitivity and specificity were pooled using a bivariate model.

Conclusion

Fibuoin-3 is a useful diagnostic marker for MPM.

The pathological and molecular diagnosis of malignant pleural mesothelioma: a literature review

Malignant pleural mesothelioma (MPM), an asbestos-induced tumor, represents significant diagnostic challenges for pathologists. Its histological diagnosis is stepwise and should be based on morphological assessment, supported by clinical and radiological findings, and supplemented with immunohistochemistry (IHC) and, more recently, molecular tests. The main diagnostic dilemmas are the differential diagnoses with benign mesothelial proliferations and other pleural malignant tumors. The present review is an update regarding the morphological, immunohistochemical, and molecular features with respect to MPM diagnosis. Data sources include a survey of the biomedical literature from PubMed (http://www.ncbi.nlm.nih.gov/pubmed) and textbooks focusing on the pathological diagnosis of MPM and associated immunohistochemical and molecular markers. The histological findings of MPM could facilitate its diagnosis and provide important prognostic information. The immunohistochemical approach should rest on the application of a panel including positive (mesothelial-related) and negative markers with greater than 80% sensitivity and specificity, which need to be selected based on morphology and clinical information. Moreover, in challenging cases, fluorescent in situ hybridization (FISH) testing for the p16 deletion and IHC to evaluate the loss of BRCA1-associated protein 1 (BAP1) expression could be useful in distinguishing benign from malignant pleural proliferations.

Capture of mesothelioma cells with 'universal' CTC-chip

Malignant mesothelioma (MM) is a highly aggressive malignant tumor, predominantly associated with job-related exposure to asbestos. Development of effective and non-invasive modalities for diagnosis is an important issue in occupational medicine. Circulating tumor cells (CTCs), which are tumor cells that are shed from primary tumors and circulate in the peripheral blood, may be detected at an earlier stage than malignant tumors, and detection of CTCs may provide a novel insight into the diagnosis of MM. In a previous study evaluating clinical utility of CTCs, detected with a widely used system 'CellSearch', the authors indicated a significant however insufficient capability in the diagnosis of MM, suggesting need for a more sensitive system. Accordingly, the authors developed a novel microfluidic system to capture CTCs (CTC-chip), and demonstrated that the CTC-chip effectively captured MM cells (ACC-MESO-4) spiked in the blood by conjugating an anti-podoplanin antibody. The results of the present study demonstrated that the CTC-chip coated with the anti-podoplanin antibody captured another MM cell (ACC-MESO-1). However, the capture efficiencies were lower than those for ACC-MESO-4. In addition, an anti-mesothelin antibody was used to capture CTCs, however the CTC-chip coated with the anti-mesothelin antibody failed to effectively capture MM cells, possibly due to low mesothelin expression. Overall, the CTC-chip may capture specific types of CTCs by conjugating any antibody against an antigen expressed on CTCs, and may be a useful system for the diagnosis of malignant tumors, including MM.

Ex vivo evaluation of tumor cell specific drug responses in malignant pleural effusions

The effect of chemotherapy may be improved by combining the most effective drugs based on testing the sensitivity of the individual tumor ex vivo. Such estimations of tumor cells from effusions have so far not been implemented in the clinical routine as a basis for individualized choice of therapy. One obstacle for such analyses is the admixture of benign cells that might obscure the results. In this paper we test and compare two ways of performing the analysis specifically on tumor cells. First we enrich the tumor cells, using antibody labeled magnetic separation, and measure the effects of subsequent drug exposure with the metabolic activity assays WST-1 and alamar blue. The second way of estimating drug effects specifically on tumor cells employs multi parameter flow cytometry, measuring apoptosis with the propidium iodide / AnnexinV technique and, particularly for pemetrexed, possible effects on cell cycle progression in immunologically identified tumor cells. The two techniques produce similar results, indicating a possible use in personalized medicine. The possible predictive role of the analysis remains to be shown.

Immunotherapy advances for mesothelioma treatment

INTRODUCTION

Mesothelioma is a rare type of cancer that is strongly tied to asbestos exposure. Despite application of different modalities such as chemotherapy, radiotherapy and surgery, patient prognosis remains very poor and therapies are ineffective. Much research currently focuses on the application of novel approaches such as immunotherapy towards this disease. Areas covered: The types, stages and aetiology of mesothelioma are detailed, followed by a discussion of the current treatment options such as radiotherapy, surgery, and chemotherapy. A description of innate and adaptive immunity and the principles and justification of immunotherapy is also included. Clinical trials for different immunotherapeutic modalities are described, and lastly the article closes with an expert commentary and five-year view, the former of which is summarised below. Expert commentary: Current efforts for novel mesothelioma therapies have been limited by attempting to apply treatments from other cancers, an approach which is not based on a solid understanding of mesothelioma biology. In our view, the influence of the hostile, hypoxic microenvironment and the gene expression and metabolic changes that resultantly occur should be characterised to improve therapies. Lastly, clinical trials should focus on overall survival rather than surrogate endpoints to avoid bias and inaccurate reflections of treatment effects.

Anti-CTLA-4 therapy for malignant mesothelioma

Immunotherapy is an emerging therapeutic strategy with a promising clinical outcome in some solid tumors, particularly metastatic melanoma. One approach to immunotherapy is immune checkpoint inhibitors, such as blockage of CTLA-4 and PD-1/PD-L1. This special report aims to describe the state of clinical trials of tremelimumab in patients with unresectable malignant mesothelioma (MM) in particular with regard to the clinical efficacy, safety and tolerability. Criticism and perspective of this treatment are also discussed. Biological and clinical considerations rule out the use of tremelimumab as single agent for MM and, more generally, the use of immune checkpoint inhibitors for MM is still largely questionable and not supported by evidences.

Video assisted thoracoscopic and open chest surgery in diagnosis and treatment of malignant pleural diseases

Parenchymal cancers of lung, breast, gastrointestinal tract and ovaries as well as lymphomas and mesotheliomas are among the most common cancer types causing malignant effusions, though almost all tumour types have been reported to cause a malignant effusion. The prognosis heavily depends on patients' response to systemic therapy however, regardless of the causing pathology and histopathologic form, malignant pleural disease is normally associated with a poor prognosis. To date, there are not sufficient data to allow accurate predictions of survival that would facilitate decision making for managing patients with malignant pleural diseases. Interventions are directed towards drainage of the effusion and, when appropriate, concurrent or subsequent pleurodesis or establishing long-term drainage to prevent re-accumulation. The rate of re-accumulation of the pleural effusion, the patient's prognosis, and the severity of the patient's symptoms should guide the subsequent choice of therapy. In contemporary medicine, not many cancers have managed to generate as intense debates concerning treatment, as malignant pleural mesothelioma. The relative advantages of surgery, radiation, chemotherapy and any combination of the three are continuously reassessed and reconsidered, even though not always based on scientific evidence. The aim of surgery in mesothelioma may be prolongation of life, in addition to palliation of symptoms. Longer recovery periods from more extensive surgical procedures could be justified, in carefully selected patients. Surgical options include: Video assisted thoracoscopic (VATS) pleurodesis, VATS partial pleurectomy (VATS PP)-both parietal and visceral; open pleurectomy decortication (PD)-with an extended option (EPD) and extrapleural pneumonectomy (EPP). Current evidence implies that EPD can be performed reliably in specialised centres with good results, both in terms of mortality and survival; however, no operation has yet been shown to be beneficial in a prospective randomized controlled clinical trial.

Tissue transglutaminase (TG2) enables survival of human malignant pleural mesothelioma cells in hypoxia

Malignant pleural mesothelioma (MPM) is an aggressive tumor linked to environmental/occupational exposure to asbestos, characterized by the presence of significant areas of hypoxia. In this study, we firstly explored the expression and the role of transglutaminase 2 (TG2) in MPM cell adaptation to hypoxia. We demonstrated that cells derived from biphasic MPM express the full-length TG2 variant at higher levels than cells derived from epithelioid MPM and normal mesothelium. We observed a significant induction of TG2 expression and activity when cells from biphasic MPM were grown as a monolayer in chronic hypoxia or packed in spheroids, where the presence of a hypoxic core was demonstrated. We described that the hypoxic induction of TG2 was HIF-2 dependent. Importantly, TGM2-v1 silencing caused a marked and significant reduction of MPM cell viability in hypoxic conditions when compared with normoxia. Notably, a TG2-selective irreversible inhibitor that reacts with the intracellular active form of TG2, but not a non-cell-permeable inhibitor, significantly compromised cell viability in MPM spheroids. Understanding the expression and function of TG2 in the adaptation to the hypoxic environment may provide useful information for novel promising therapeutic options for MPM treatment.

KDM6B histone demethylase is an epigenetic regulator of estrogen receptor β expression in human pleural mesothelioma

AIM

To assess the correlation between KDM6B and estrogen receptor β (ERβ) expression in malignant pleural mesothelioma (MPM).

MATERIALS & METHODS

We evaluated gene expression by in silico analysis of microarray data, real-time PCR and western blot in MPM tumors and cell lines.

RESULTS & CONCLUSION

We report a strong positive correlation between the expression of KDM6B and ERβ in MPM tumors and cell lines. We describe that, in hypoxia, the HIF2α-KDM6B axis induces an epithelioid morphology and ERβ expression in biphasic MPM cells with estrogen receptor-negative phenotype. Reduced histone H3K27 tri-methylation confirms KDM6B activity under hypoxic conditions. Importantly, cells treated during reoxygenation with the selective ERβ agonist, KB9520, maintain ERβ expression and the less aggressive phenotype acquired in hypoxia.

CTLA-4 in mesothelioma patients: tissue expression, body fluid levels and possible relevance as a prognostic factor

CTLA-4 function as a negative regulator of T cell-mediated immune response is well established, whereas much less is known about the immunoregulatory role of its soluble isoform (sCTLA-4). No data are available on CTLA-4 expression and prognostic impact in malignant pleural mesothelioma (MPM). We investigated, by immunohistochemistry, CTLA-4 expression in tumor tissues and, by ELISA, sCTLA-4 levels in sera and matched pleural effusions from 45 MPM patients. Prognostic effect of CTLA-4 expression on overall survival (OS) was assessed through Cox regression and prognostic significance expressed as death rate ratio (HR). We found that 56.0 % of MPM tissues expressed CTLA-4 with variable intensity and percentage of positive cells estimated by the immunoreactive score. sCTLA-4 levels were significantly higher in sera (S-sCTLA-4) than in pleural effusions (PE-sCTLA-4) (geometric mean ratio = 2.70, P value = 0.020). CTLA-4 expression at the tissue level was higher in the epithelioid histological subtype than in the sarcomatoid, whereas at the serum level, it was higher in the sarcomatoid subtype. A homogeneous favorable prognostic effect was found for CTLA-4 overexpression in tissue, serum and pleural effusion. Interestingly, only the PE-sCTLA-4 was found to be a statistically significant positive prognostic factor (HR = 0.37, 95 % CI = 0.18-0.77, P value = 0.007). Indeed, PE-sCTLA-4 correlated with CTLA-4 expression in tissues, whereas this latter expression showed a weak association with OS. To confirm our findings, further experimental evidences obtained from a larger cohort of MPM patients are required. However, our results would indicate a positive correlation of PE-sCTLA-4 levels and OS in MPM patients.

Metastatic malignant pleural mesothelioma masquerading as a case of acute abdomen secondary to small bowel perforation

Metastatic pleural mesothelioma is a rare disease. The present study aimed to report a rare presentation of metastatic malignant mesothelioma (MM). The patient was an elderly man who presented with small bowel (jejunal) perforation secondary to metastatic pleural mesothelioma deposits. This was a rare presentation of a rare disease and the first reported case in the published studies in which MM masqueraded as bowel perforation prior to the primary diagnosis.

SIMILAR CASES PUBLISHED

1.

Guidelines for the Cytopathologic Diagnosis of Epithelioid and Mixed-Type Malignant Mesothelioma: a secondary publication

OBJECTIVE

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma.

DATA SOURCES

Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks.

RATIONALE

This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Hippo pathway gene mutations in malignant mesothelioma: revealed by RNA and targeted exon sequencing

INTRODUCTION

Malignant mesothelioma (MM) is an aggressive neoplasm causatively associated with exposure to asbestos. MM is rarely responsive to conventional cytotoxic drugs, and the outcome remains dismal. It is, therefore, necessary to identify the signaling pathways that drive MM and to develop new therapeutics specifically targeting the molecules involved.

METHODS

We performed comprehensive RNA sequencing of 12 MM cell lines and four clinical samples using so-called next-generation sequencers.

RESULTS

We found 15 novel fusion transcripts including one derived from chromosomal translocation between the large tumor suppressor 1 (LATS1) and presenilin-1 (PSEN1) genes. LATS1 is one of the central players of the emerging Hippo signaling pathway. The LATS1-PSEN1 fusion gene product lacked the ability to phosphorylate yes-associated protein and to suppress the growth of a MM cell line. The wild-type LATS1 allele was undetectable in this cell line, indicating two-hit genetic inactivation of its tumor suppressor function. Using pathway-targeted exon sequencing, we further identified a total of 11 somatic mutations in four Hippo pathway genes (neurofibromatosis type 2 [NF2], LATS2, RASSF1, and SAV1) in 35% (8 of 23) of clinical samples. Nuclear staining of yes-associated protein was detected in 55% (24 of 44) of the clinical samples. Expression and/or phosphorylation of the Hippo signaling proteins, RASSF1, Merlin (NF2), LATS1, and LATS2, was frequently absent.

CONCLUSIONS

The frequent alterations of Hippo pathway molecules found in this study indicate the therapeutic feasibility of targeting this pathway in patients with MM.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma: Complementary Statement from the International Mesothelioma Interest Group, Also Endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology

OBJECTIVE

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma.

DATA SOURCES

Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks.

RATIONALE

This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Comparative proteomic analysis of malignant pleural mesothelioma: Focusing on the biphasic subtype

Malignant pleural mesothelioma (MPM) is a rare cancer originated from pleural mesothelial cells. MPM has been associated with long-term exposure to asbestos. In this work we performed a comparative proteomic analysis of biphasic pleural mesothelioma (B-PM). Tissue biopsies were obtained from 61 patients who were subjected to a diagnostic thoracoscopy. 2D/MS based approach was used for proteomic analysis. The 22 proteins found differentially expressed in B-PM, with respect to benign, were analyzed by Ingenuity Pathways Analysis and compared with those obtained for epitheliod pleural mesothelioma (E-PM). A different activation of transcription factors, proteins and cytokines were observed between two subtypes.

Guidelines for cytopathologic diagnosis of epithelioid and mixed type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma (MM). Cytopathologists involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC), who have an interest in the field contributed to this update. Reference material includes peer-reviewed publications and textbooks. This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists, who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in cape town. During the previous IMIG biennial meetings, thorough discussions have resulted in published guidelines for the pathologic diagnosis of MM. However, previous recommendations have stated that the diagnosis of MM should be based on histological material only.[12] Accumulating evidence now indicates that the cytological diagnosis of MM supported by ancillary techniques is as reliable as that based on histopathology, although the sensitivity with cytology may be somewhat lower.[345] Recognizing that noninvasive diagnostic modalities benefit both the patient and the health system, future recommendations should include cytology as an accepted method for the diagnosis of this malignancy.[67] The article describes the consensus of opinions of the authors on how cytology together with ancillary testing can be used to establish a reliable diagnosis of MM.

Downregulation of TBXAS1 in an iron-induced malignant mesothelioma model

Malignant mesothelioma is an aggressive and therapy-resistant neoplasm arising from mesothelial cells. Evidence suggests that the major pathology associated with asbestos-induced mesothelioma is local iron overload. In the present study, we induced iron-induced mesothelioma in rats based on previous reports. Ten Wistar rats were given ferric saccharate and nitrilotriacetate i.p. for 5 days a week. Five of the ten rats exhibited widespread mesotheliomas in the peritoneum and tunica vaginalis. The tumor cells showed positive immunostaining for calretinin, wilms tumor-1, podoplanin and the oxidative DNA marker 8-hydroxy-2′-deoxyguanosine. In three of the five rats with mesothelioma, array-based comparative genomic hybridization analysis identified a common chromosomal deletion mapped to the chromosomal 4q31 locus, which encompasses the TBXAS1 gene. Downregulation of the TBXAS1 gene was confirmed using quantitative PCR. TBXAS1 gene expression was also reduced in three of four human malignant pleural mesothelioma cell lines compared with normal bronchial epithelial cells. Immunohistochemistry revealed that TBXAS1 expression was weakly positive and positive in five and three out of eight human malignant mesothelioma samples, respectively. In conclusion, TBXAS1 gene expression was downregulated in rats with iron-induced mesothelioma. The relationship between iron overload and TBXAS1 downregulation should be pursued further.

Prognostic value of several biomarkers for the patients with malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive tumor of the pleura closely related to asbestos exposure. Rare as it is, the incidence of MPM is predicted to increase mainly as a result of a lengthy latency period from the initial asbestos exposure, making it a public health concern for the next decades. Moreover, the patients with MPM have an extremely poor prognosis due to its high resistance to conventional oncologic treatments and delayed diagnosis. Although the result of current therapeutic modalities based on patient features and clinical stages is very frustrating, great advances have been shown in the knowledge of molecular biology of MPM in recent years. This is accompanied by dozens of putative prognostic biomarkers that are actively involved in tumor biological activities. These prognostic candidates can offer us a new insight into the biological characteristics of MPM, contributing to development of individualized therapeutic strategies directed against oncogenesis and tumor progression. Thus, personalized approaches based on the molecular biology of the patient's tissue or body fluid will potentially improve the present disappointing outcome, bringing new hope for patients with MPM. This article reviews the principal and several novel biomarkers that can have an influence on prognosis, in the hope that they can provide us with a more profound understanding of the biology of this lethal disease.

Combinatorial anti-angiogenic gene therapy in a human malignant mesothelioma model

Anti-angiogenic gene therapy represents a promising strategy for cancer; however, it has rarely been tested in malignant mesothelioma, a highly aggressive tumor associated with asbestos with poor prognosis. In the present study, we investigated whether anti-angiogenic factors such as angiostatin, endostatin and the soluble form of vascular endothelial growth factor receptor 2 (sFlk1) were able to inhibit endothelial cell proliferation via lentivirus-mediated gene transfer into malignant mesothelioma cells in culture. We also assessed whether a dual-agent strategy had greater therapeutic benefit. Human malignant pleural mesothelioma MSTO-211H cells were transduced using lentiviral vectors that individually expressed angiostatin, endostatin and sFlk1 and linked to enhanced green fluorescent protein (EGFP) marker gene expression via an internal ribosome entry site. The lentivirus expressing EGFP alone was used as a control. The resultant cells designated as MSTO-A, MSTO-E, MSTO-F and MSTO-C were confirmed by western blot analysis and fluorescence microscopy to stably express the corresponding proteins. No differences were observed in the in vitro growth rates between any of these cells. However, co-culture of MSTO-A, MSTO-E and MSTO-F showed significant suppression of human umbilical endothelial cell growth in vitro compared with that of MSTO-C. Furthermore, a combination of any two among MSTO-A, MSTO-E and MSTO-F significantly enhanced efficacy. These results suggest that combinatorial anti-angiogenic gene therapy targeting different pathways of endothelial growth factor signaling has the potential for greater therapeutic efficacy than that of a single-agent regimen.

High Incidence of Somatic BAP1 alterations in sporadic malignant mesothelioma

BACKGROUND

Breast cancer 1-associated protein 1 (BAP1) is a nuclear deubiquitinase that regulates gene expression, transcription, DNA repair, and more. Several findings underscore the apparent driver role of BAP1 in malignant mesothelioma (MM). However, the reported frequency of somatic BAP1 mutations in MM varies considerably, a discrepancy that appeared related to either methodological or ethnical differences across various studies.

METHODS

To address this discrepancy, we carried out comprehensive genomic and immunohistochemical (IHC) analyses to detect somatic BAP1 gene alterations in 22 frozen MM biopsies from U.S. MM patients.

RESULTS

By combining Sanger sequencing, multiplex ligation-dependent probe amplification, copy number analysis, and cDNA sequencing, we found alteration of BAP1 in 14 of 22 biopsies (63.6%). No changes in methylation were observed. IHC revealed normal nuclear BAP1 staining in the eight MM containing wild-type BAP1, whereas no nuclear staining was detected in the 14 MM biopsies containing tumor cells with mutated BAP1. Thus, IHC results were in agreement with those obtained by genomic analyses. We then extended IHC analysis to an independent cohort of 70 MM biopsies, of which there was insufficient material to perform molecular studies. IHC revealed loss of BAP1 nuclear staining in 47 of these 70 MM biopsies (67.1%).

CONCLUSIONS

Our findings conclusively establish BAP1 as the most commonly mutated gene in MM, regardless of ethnic background or other clinical characteristics. Our data point to IHC as the most accessible and reliable technique to detect BAP1 status in MM biopsies.

Investigations on dendrimer space reveal solid and liquid tumor growth-inhibition by original phosphorus-based dendrimers and the corresponding monomers and dendrons with ethacrynic acid motifs

The well-known reactive diuretic ethacrynic acid (EA, Edecrin), with low antiproliferative activities, was chemically modified and grafted onto phosphorus dendrimers and the corresponding simple branched phosphorus dendron-like derivatives affording novel nanodevices showing moderate to strong antiproliferative activities against liquid and solid tumor cell lines, respectively.

Mesothelioma in Mongolia: case report

BACKGROUND

More than 80% of cases of mesothelioma worldwide have a history of asbestos exposure. In Mongolia, workers in coal burning thermal power plants (TPP) have widely utilized asbestos as an insulation material.

METHODS

We describe the case of a 47-year-old woman diagnosed with a malignant pleural mesothelioma. She worked in a TPP in Ulaanbaatar, Mongolia for 28 years.

RESULTS

A computer tomography (CT) scan showed a circumferential ring around her left lung, and tissues' samples had a biphasic variant of mesothelioma with epithelioid and sarcomatoid components.

DISCUSSION

This is the first reported case of mesothelioma in Mongolia. We expect additional cases of mesothelioma, as well as other asbestos related diseases, will be identified in the future. In order to properly track asbestos related diseases in the country, we recommend the creation of an asbestos related disease registry.

Localized malignant pleural mesothelioma with renal metastasis

Localized malignant pleural mesothelioma (LMM) is a rare subset of malignant pleural mesothelioma. Its epidemiology, biology, natural history and optimal treatment are poorly understood. We report a case of LMM treated aggressively with complete surgical resection and adjuvant radiotherapy, but subsequently complicated by local chest wall recurrence and solitary metastasis to the kidney. This case is examined in the context of a small number of cases of LMM in the literature to emphasize the existence of this rare disease entity, their unusual biological behaviour and the need for further tumour molecular and genomic research.