Biomarkers in mesothelioma

Intrapleural injection of brucea javanica oil emulsion provided a long-term benefits in patient with malignant pleural effusion from pleural mesothelioma: A case report

Malignant pleural mesothelioma (MPM) is a severe form of cancer that originates from mesothelium cells. Around 54-90% of mesotheliomas are associated with pleural effusions. Brucea Javanica Oil Emulsion (BJOE) is the processed oil derived from the seeds of Brucea javanica, which has shown potential as a treatment option for several types of cancer. Here, we present a case study of a MPM patient with malignant pleural effusion who received intrapleural injection of BJOE. The treatment resulted in the complete response of pleural effusion and chest tightness. While the precise mechanisms underlying the therapeutic effects of BJOE for pleural effusion are not yet fully understood, it has demonstrated a satisfactory clinical response without significant adverse effects.

Pleural Mesothelioma in the Era of Immunotherapy

Over the course of the last decade, immunotherapy has revolutionised the management of a great number of cancer types. The treatment of pleural mesothelioma, a rare and highly aggressive cancer, is also being transformed by immunotherapy. The recent combination of ipilimumab and nivolumab improved overall survival compared with platinum-based chemotherapy, irrespective of the histology, establishing immunotherapy as a front-line standard of care in advanced pleural mesothelioma. Yet, most patients do not derive long-term benefit from any of the available therapies, and we note a significant lack of predictive and prognostic biomarkers. After progressing on first-line therapy, patients have limited therapeutic options, and data are scarce about optimal sequencing. In this perspective, we discuss the current management of pleural mesothelioma, defining what we consider to be the therapeutic sequence based on performance status and tumour histology. We also highlight promising ongoing trials that could further shape the management of this rare disease.

Epigenetic investigation into circulating microRNA 197-3p in sera from patients affected by malignant pleural mesothelioma and workers ex-exposed to asbestos

The epigenetic role of microRNAs is established at both physiological and pathological levels. Dysregulated miRNAs and their targets appear to be a promising approach for innovative anticancer therapies. In our previous study, circulating miR-197-3p tested dysregulated in workers ex-exposed to asbestos (WEA). Herein, an epigenetic investigation on this circulating miRNA was carried out in sera from malignant pleural mesothelioma (MPM) patients. MiR-197-3p was quantified in MPM (n = 75) sera and comparatively analyzed to WEA (n = 75) and healthy subject (n = 75) sera, using ddPCR and RT-qPCR techniques. Clinicopathological characteristics, occupational, non-occupational information and overall survival (OS) were evaluated in correlation studies. MiR-197-3p levels, analyzed by ddPCR, were significantly higher in MPM than in WEA cohort, with a mean copies/µl of 981.7 and 525.01, respectively. Consistently, RT-qPCR showed higher miR-197-3p levels in sera from MPM with a mean copies/µl of 603.7, compared to WEA with 336.1 copies/µl. OS data were significantly associated with histologic subtype and pleurectomy. Circulating miR-197-3p is proposed as a new potential biomarker for an early diagnosis of the MPM onset. Indeed, miR-197-3p epigenetic investigations along with chest X-ray, computed tomography scan and spirometry could provide relevant information useful to reach an early and effective diagnosis for MPM.

Fibrosis in Mesothelioma: Potential Role of Lysyl Oxidases

Immunotherapies (such as checkpoint inhibitors) and standard chemotherapies (such as cisplatin) have limitations in the successful treatment of malignant pleural mesothelioma (MPM). Fibrosis is the accumulation of collagen in the extracellular matrix (ECM) of tissues, making them denser than that of healthy tissues and thereby affecting drug delivery and immune cell infiltration. Moreover, fibrosis severely affects the patient's breathing and quality of life. The production of collagen and its assembly is highly regulated by various enzymes such as lysyl oxidases. Many solid tumors aberrantly express the family of lysyl oxidases (LOX/LOXL). This review examines how LOX/LOXLs were found to be dysregulated in noncancerous and cancerous settings, discusses their roles in solid tumor fibrosis and pathogenesis and explores the role of fibrosis in the development and poor clinical outcomes of patients with MPM. We examine the current preclinical status of drugs targeting LOX/LOXLs and how the incorporation of such drugs may have therapeutic benefits in the treatment and management of patients with MPM.

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.

Clinical utility of diagnostic biomarkers in malignant pleural mesothelioma: a systematic review and meta-analysis

Malignant pleural mesothelioma (MPM) is characterised by late-stage diagnosis and poor prognosis. Currently, no screening tool is advocated and diagnosis is based on invasive techniques, which are not well tolerated. Non-invasive diagnostic biomarkers have shown potential and could have a huge clinical benefit. However, despite extensive research, there is no consensus yet on their clinical use, with many articles reporting contradicting results, limiting their clinical implementation. The aim of this systematic review is therefore to explore the different semi- and non-invasive diagnostic markers in several human matrices and identify those that might clinically be relevant. A total of 100 articles were selected through Web of Science and PubMed, with 56 articles included in the quantitative analysis. Although many studies have reported on the diagnostic accuracy of MPM biomarkers such as serum mesothelin and high-mobility group box protein 1 and plasma fibulin-3, none have resulted in a validated test for early detection. Future research should focus on external validation, combinations into biomarker panels, the inclusion of early stage MPM patients and a combination of different biomarker matrices, as well as new markers.

Diagnostic biomarkers for malignant pleural mesothelioma seem promising; however, further research is necessary to prove their clinical value. This review provides a thorough overview of the different markers and compares them in several matrices.https://bit.ly/35ni6UO

Diagnostic and Prognostic Value of Three microRNAs in Environmental Asbestiform Fibers-Associated Malignant Mesothelioma

Fluoro-edenite (FE) is an asbestiform fiber identified in Biancavilla (Sicily, Italy). Environmental exposure to FE has been associated with a higher incidence of malignant mesothelioma (MM). The present study aimed to validate the predicted diagnostic significance of hsa-miR-323a-3p, hsa-miR-101-3p, and hsa-miR-20b-5p on a subset of MM patients exposed to FE and matched with healthy controls. For this purpose, MM tissues vs. nonmalignant pleura tissues were analyzed through droplet digital PCR (ddPCR) to evaluate differences in the expression levels of the selected miRNAs and their MM diagnostic potential. In addition, further computational analysis has been performed to establish the correlation of these miRNAs with the available online asbestos exposure data and clinic-pathological parameters to verify the potential role of these miRNAs as prognostic tools. ddPCR results showed that the three analyzed miRNAs were significantly down-regulated in MM cases vs. controls. Receiver operating characteristic (ROC) analysis revealed high specificity and sensitivity rates for both hsa-miR-323a-3p and hsa-miR-20b-5p, which thus acquire a diagnostic value for MM. In silico results showed a potential prognostic role of hsa-miR-101-3p due to a significant association of its higher expression and increased overall survival (OS) of MM patients.

Management of Pleural Effusion Secondary to Malignant Mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive pleural tumour which has been epidemiologically linked to occupational exposure to asbestos. MPM is often associated with pleural effusion, which is a common cause of morbidity and whose management remains a clinical challenge. In this review, we analysed the literature regarding the diagnosis and therapeutic options of pleural effusion secondary to mesothelioma. Our aim was to provide a comprehensive view on this subject, and a new algorithm was proposed as a practical aid to clinicians dealing with patients suffering from pleural effusion.

Ancillary Diagnostic Investigations in Malignant Pleural Mesothelioma

For a number of patients presenting with an undiagnosed pleural effusion, frailty, medical co-morbidity or personal choice may preclude the use of pleural biopsy, the gold standard investigation for diagnosis of malignant pleural mesothelioma (MPM). In this review article, we outline the most recent evidence on ancillary diagnostic tests which may be used to support a diagnosis of MPM where histological samples cannot be obtained or where results are non-diagnostic. Immunocytochemical markers, molecular techniques, diagnostic biomarkers and imaging techniques are discussed. No adjunctive test has a sensitivity and specificity profile to support use in isolation; however, correlation of pleural fluid cytology with relevant radiology and supplementary biomarkers can enable an MDT-consensus clinico-radiological-cytological diagnosis to be made where further invasive tests are not possible or not appropriate. Diagnostic challenges surrounding non-epithelioid MPM are recognised, and there is a critical need for reliable and non-invasive investigative tools in this population.

Immunohistochemical Expression of Serine and Arginine-Rich Splicing Factor 1 (SRSF1) in Fluoro-Edenite-Induced Malignant Mesothelioma: A Preliminary Study

The Serine and Arginine-Rich Splicing Factor 1 (SRSF1) has a proto-oncogenic function, being associated with angiogenesis and frequently overexpressed in many human malignant neoplasms. Its immunohistochemical expression has never been investigated in malignant pleural mesothelioma (MPM). We evaluated SRSF1 immunoexpression and its possible relation to angiogenesis in a selected cohort of 10 fluoro-edenite(FE)-induced MPM cases. Methods: Immunohistochemical analyses with an anti-SRSF1 antibody were performed. We interpreted the cases as positive if tumor cell nuclei were stained; a semi-quantitative analysis of the cases was performed by evaluating the intensity of staining and the percentage of tumor positive cells. A microvessel density (MVD) count was also performed. Results: High and low immunoexpressions of SRSF1 were seen in six and four MPMs, respectively. A trend of shorter overall survival was found in FE-induced MPM patients with SRSF1 overexpression. In addition, a significant association between high-MVD and high SRSF1 immunoexpression (p = 0.0476) was found. Conclusions: SRSF1 appears to be involved in MPM pathogenesis and its immunoexpression may represent a prognostic biomarker capable of identifying subgroups of patients with different prognosis. However, given the preliminary nature of the present study, further investigations on larger series, and additional in vitro studies, are required to validate our findings.

Putative Biomarkers for Malignant Pleural Mesothelioma Suggested by Proteomic Analysis of Cell Secretome

BACKGROUND

Malignant pleural mesothelioma (MPM) a rare neoplasm linked to asbestos exposure is characterized by a poor prognosis. Soluble mesothelin is currently considered the most specific diagnostic biomarker. The aim of the study was to identify novel biomarkers by proteomic analysis of two MPM cell lines secretome.

MATERIALS AND METHODS

The protein patterns of MPM cells secretome were examined and compared to a non-malignant mesothelial cell line using two-dimensional gel electrophoresis coupled to mass spectrometry. Serum levels of candidate biomarkers were determined in MPM patients and control subjects.

RESULTS

Two up-regulated proteins involved in cancer biology, prosaposin and quiescin Q6 sulfhydryl oxidase 1, were considered candidate biomarkers. Serum levels of both proteins were significantly higher in MPM patients than control subjects. Combining the data of each receiver-operating characteristic analysis predicted a good diagnostic accuracy.

CONCLUSION

A panel of the putative biomarkers represents a promising tool for MPM diagnosis.

A liquid biopsy for detecting circulating mesothelial precursor cells: A new biomarker for diagnosis and prognosis in mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is an aggressive cancer related to asbestos exposure. Early diagnosis is challenging due to generic symptoms and a lack of biomarkers. We previously demonstrated that mesothelial precursor cells (MPC) characterized by mesothelin (MSLN)+CD90+CD34+ could be implicated in the development of mesothelioma after asbestos exposure. Here, we aimed to determine the clinical significance of detecting MPC in blood for early-stage diagnosis and prognosis of mesothelioma.

METHODS

Due to the rarity of MPC in blood, it is challenging to identify this cell population using conventional techniques. Hence, we have developed a microfluidic liquid biopsy platform called MesoFind that utilizes an immunomagnetic, mesothelin capture strategy coupled with immunofluorescence to identify rare populations of cells at high sensitivity and precision. To validate our technique, we compared this approach to flow cytometry for the detection of MPC in murine blood and lavage samples. Upon successful validation of the murine samples, we then proceeded to examine circulating MPC in 23 patients with MPM, 23 asbestos-exposed individuals (ASB), and 10 healthy donors (HD) to evaluate their prognostic and diagnostic value.

FINDING

MPC were successfully detected in the blood of murine samples using MesoFind but were undetectable with flow cytometry. Circulating MPC were significantly higher in patients with epithelioid MPM compared to HD and ASB. The MPC subpopulation, MSLN+ and CD90+, were upregulated in ASB compared to HD suggesting an early role in pleural damage from asbestos. The MPC subpopulation, MSLN+ and CD34+, in contrast, were detected in advanced MPM and associated with markers of poor prognosis, suggesting a predominant role during cancer progression.

INTERPRETATION

The identification of circulating MPC presents an attractive solution for screening and early diagnosis of epithelioid mesothelioma. The presence of different subtypes of MPC have a prognostic value that could be of assistance with clinical decisions in patients with MPM.

FUNDING

Princess Margaret Hospital Foundation Mesothelioma Research Fund, Toronto General & Western Hospital Foundation.

Update of in vitro, in vivo and ex vivo fluoro-edenite effects on malignant mesothelioma: A systematic review (Review)

Fluoro-edenite (FE), asbestiform fiber found in Biancavilla (Sicily, Italy), presents various characteristics similar to the asbestos group, in particular two fibrous phases tremolite and actinolite. Indeed, epidemiological studies have shown that FE fibers have similar effects to those of asbestos fibers. Such studies have reported a high incidence of malignant mesothelioma (MM), an aggressive neoplasm of the serosal membranes lining the pleural cavity, in individuals residing there due to FE exposure in Biancavilla related to environmental contamination. Evidence has led to the classification of FE as a Group 1 human carcinogen by the International Agency for Research on Cancer (IARC). The aim of this systematic review is to compare the results achieved in in vitro, in vivo and ex vivo experimental studies involving FE in order to update the current knowledge on the pathogenesis and molecular mechanisms responsible for FE-mediated MM development as well as the availability of effective biomarkers for MM prevention and diagnosis. This review is focused on the pathophysiological mechanisms mediated by inflammation induced by FE fiber exposure and which are responsible for MM development. This review also discusses the discovery of new diagnostic and prognostic biomarkers for the management of this pathology. It is known that the risk of cancer development increases with chronic inflammation, arising from enhanced reactive oxygen species (ROS) and NO^• production stimulated by the body to remove exogenous agents, causing DNA damage and enhanced signal transduction that may lead to activation of oncogenes. Studies concerning MM biomarker discovery indicate that several biomarkers have been proposed for MM, but mesothelin is the only Food and Drug Administration (FDA)-approved biomarker for MM, with limitations. In recent studies, in silico analysis to identify selected miRNAs highly deregulated in cancer samples when compared with normal control have been developed. This in silico approach could represent an effort in the field of biomarker discovery for MM.

S100A4 is a Biomarker of Tumorigenesis, EMT, Invasion, and Colonization of Host Organs in Experimental Malignant Mesothelioma

Recent findings suggest that S100A4, a protein involved in communication between stromal cells and cancer cells, could be more involved than previously expected in cancer invasiveness. To investigate its cumulative value in the multistep process of the pathogenesis of malignant mesothelioma (MM), SWATH-MS (sequential window acquisition of all theoretical fragmentation spectra), an advanced and robust technique of quantitative proteomics, was used to analyze a collection of 26 preneoplastic and neoplastic rat mesothelial cell lines and models of MM with increasing invasiveness. Secondly, proteomic and histological analyses were conducted on formalin-fixed paraffin-embedded sections of liver metastases vs. primary tumor, and spleen from tumor-bearing rats vs. controls in the most invasive MM model. We found that S100A4, along with 12 other biomarkers, differentiated neoplastic from preneoplastic mesothelial cell lines, and invasive vs. non-invasive tumor cells in vitro, and MM tumors in vivo. Additionally, S100A4 was the only protein differentiating preneoplastic mesothelial cell lines with sarcomatoid vs. epithelioid morphology in relation to EMT (epithelial-to-mesenchymal transition). Finally, S100A4 was the most significantly increased biomarker in liver metastases vs. primary tumor, and in the spleen colonized by MM cells. Overall, we showed that S100A4 was the only protein that showed increased abundance in all situations, highlighting its crucial role in all stages of MM pathogenesis.

Malignant Pleural Effusion and Its Current Management: A Review

Malignant pleural effusion (MPE) is an exudative effusion with malignant cells. MPE is a common symptom and accompanying manifestation of metastatic disease. It affects up to 15% of all patients with cancer and is the most common in lung, breast cancer, lymphoma, gynecological malignancies and malignant mesothelioma. In the last year, many studies were performed focusing on the pathophysiological mechanisms of MPE. With the advancement in molecular techniques, the importance of tumor-host cell interactions is becoming more apparent. Additionally, the process of pathogenesis is greatly affected by activating mutations of EGFR, KRAS, PIK3CA, BRAF, MET, EML4/ALK and RET, which correlate with an increased incidence of MPE. Considering all these changes, the authors aim to present a literature review of the newest findings, review of the guidelines and pathophysiological novelties in this field. Review of the just recently, after seven years published, practice guidelines, as well as analysis of more than 70 articles from the Pubmed, Medline databases that were almost exclusively published in indexed journals in the last few years, have relevance and contribute to the better understanding of the presented topic. MPE still presents a severe medical condition in patients with advanced malignancy. Recent findings in the field of pathophysiological mechanisms of MPE emphasize the role of molecular factors and mutations in the dynamics of the disease and its prognosis. Treatment guidelines offer a patient-centric approach with the use of new scoring systems, an out of hospital approach and ultrasound. The current guidelines address multiple areas of interest bring novelties in the form of validated prediction tools and can, based on evidence, improve patient outcomes. However, the role of biomarkers in a clinical setting, possible new treatment modalities and certain specific situations still present a challenge for new research.

Biomarkers for malignant pleural mesothelioma: a meta-analysis

Malignant pleural mesothelioma (MPM) is a rare but aggressive cancer, and early detection is associated with better survival. Mesothelin, fibulin-3 and osteopontin have been suggested as screening biomarkers. The study conducted a meta-analysis of the mean differences of mesothelin, osteopontin and fibulin-3 in blood and pleural samples. PubMed searches were conducted for studies that measured levels of mesothelin, osteopontin and fibulin-3 in participants with MPM compared with malignancy, benign lung disease or healthy participants. Thirty-two studies with mesothelin levels, 12 studies with osteopontin levels and 9 studies with fibulin-3 levels were included in the meta-analysis. Statistically significant mean differences were seen between MPM patients and all other comparison groups for mesothelin blood and pleural levels. Statistically significant differences in blood osteopontin levels were seen between participants with benign lung disease and healthy participants compared with participants with MPM, but not when comparing participants with cancer with MPM participants. There were not enough studies that reported osteopontin levels in pleural fluid to complete a meta-analysis. Statistically significant differences were seen in both blood and pleural levels of fibulin-3 in MPM patients compared with all other groups. On the basis of these results, mesothelin and fibulin-3 levels appear to be significantly lower in all control groups compared with those with MPM, making them good candidates for screening biomarkers. Osteopontin may be a useful biomarker for screening healthy individuals or those with benign lung disease but would not be useful for screening patients with malignancies.

HMGB1 as a Potential Biomarker and Therapeutic Target for Malignant Mesothelioma

Malignant mesothelioma (MM) is a rare, aggressive, and highly lethal cancer that is substantially induced by exposure to asbestos fibers. High-mobility group box 1 (HMGB1) is an intriguing proinflammatory molecule involved in MM. In this review, we describe the possible crucial roles of HMGB1 in carcinogenic mechanisms based on in vivo and in vitro experimental evidence and outline the clinical findings of epidemiological investigations regarding the possible roles of HMGB1 as a biomarker for MM. We conclude that novel strategies targeting HMGB1 may suppress MM cells and interfere with asbestos-induced inflammation.

The Future of Mesothelioma Research: Basic Science Research

Our current understanding of mesothelioma in terms of disease induction, development, and treatment is underpinned by decades of basic laboratory science. In this chapter, we discuss the tools that have been developed to aid our understanding of mesothelioma such as cell lines and animal models. We then go on to detail the current use and understanding of conventional therapies for mesothelioma, e.g. chemotherapy, surgery, and radiotherapy, plus their mechanisms of action, and why they may be ineffective. Finally, we discuss a range of newer treatments that are either undergoing clinical trials or are still in the earlier stages of preclinical investigation. These include a growing number of immunotherapies (e.g. checkpoint inhibitors), plus targeted therapies, the search for clinical biomarkers to predict whether patients with mesothelioma might respond to particular treatments, and combined therapies where conventional treatments may be added to newer drugs. The strategy of repositioning existing drugs, approved for other diseases, to treat mesothelioma is also discussed.

Biomarkers for Early Diagnosis and Prognosis of Malignant Pleural Mesothelioma: The Quest Goes on

Malignant pleural mesothelioma (MM) is a highly aggressive tumor characterized by a poor prognosis. Although its carcinogenesis mechanism has not been strictly understood, about 80% of MM can be attributed to occupational and/or environmental exposure to asbestos fibers. The identification of non-invasive molecular markers for an early diagnosis of MM has been the subject of several studies aimed at diagnosing the disease at an early stage. The most studied biomarker is mesothelin, characterized by a good specificity, but it has low sensitivity, especially for non-epithelioid MM. Other protein markers are Fibulin-3 and osteopontin which have not, however, showed a superior diagnostic performance. Recently, interesting results have been reported for the HMGB1 protein in a small but limited series. An increase in channel proteins involved in water transport, aquaporins, have been identified as positive prognostic factors in MM, high levels of expression of aquaporins in tumor cells predict an increase in survival. MicroRNAs and protein panels are among the new indicators of interest. None of the markers available today are sufficiently reliable to be used in the surveillance of subjects exposed to asbestos or in the early detection of MM. Our aim is to give a detailed account of biomarkers available for MM.

Immunohistochemical Expression of Aquaporin-1 in Fluoro-Edenite-Induced Malignant Mesothelioma: A Preliminary Report

BACKGROUND

The immunohistochemical expression of aquaporin-1 (AQP1) in asbestos-related malignant pleural mesothelioma (MPM) is emerging as a useful prognostic indicator of improved survival. A significantly increased incidence of MPM in a small town in southern Italy was ascribed to exposure to fluoro-edenite (FE), a naturally occurring asbestos fiber. We investigated the immunohistochemical expression of AQP1 in patients affected by FE-related MPM; taking into consideration its suggested independent prognostic role, its possible correlation with clinicopathological parameters and patient outcome was also evaluated.

METHODS

Ten patients were selected for this study, as neoplastic tissue blocks, clinical and follow-up data were available. The immunohistochemical overexpression of AQP1 was defined as ≥50% of tumor cells showing membranous staining.

RESULTS

Six cases showed AQP1 expression in ≥50% of tumor cells; in this group, a significant association of AQP1 overexpression with an increased median overall survival (OS) of 26.3 months was observed. By contrast, four patients exhibited an AQP1 score of <50% of stained cells, with a shorter median OS of 8.9 months.

CONCLUSIONS

The present study represents further confirmation of the hypothesized prognostic role of AQP1, which seems a reliable prognostic indicator.

Randomised controlled trial to compare the diagnostic yield of positron emission tomography CT (PET-CT) TARGETed pleural biopsy versus CT-guided pleural biopsy in suspected pleural malignancy (TARGET trial)

Introduction

Pleural malignancy, particularly malignant pleural mesothelioma (MPM) is increasing in incidence due to the long latency period from exposure to asbestos to development of the disease. MPM can be challenging to diagnose. For patients presenting without a pleural effusion, CT-guided biopsy remains the primary choice of biopsy, but the diagnostic sensitivity of this investigation is 70%–75%. Therefore, a proportion of patients will go on to require further biopsies. If the first biopsy is non-diagnostic, the chances of further non-diagnostic biopsies are high in MPM.

Methods

Target is a multicentre randomised controlled trial, aiming to recruit 78 patients over a 30-month period, from 10 centres in the UK. Patients will be randomised to either the standard arm which is a second CT-guided biopsy, or the interventional arm, a positron emission tomography-CT scan followed by a targeted CT-guided biopsy. Patients will be followed up for 12 months (patients recruited in the last 6 months of recruitment will have 6 months of follow-up). MPM biomarker mesothelin will be checked at baseline, 6 month and 12 month follow-up appointments where patients are able to attend these appointments.

Ethics and dissemination

Ethical approval for this trial was granted by the South West—Exeter research and ethics committee (reference number 15/SW/0156). Results of the trial will be published in a peer-reviewed journal and presented at an international conference.

Trial registration number

ISRCTN14024829; Pre-results.