Use of tumor markers for differential diagnosis of mesothelioma and secondary pleural malignancies

Pleural Mesothelioma: Advances in Blood and Pleural Biomarkers

Pleural mesothelioma (PM) is a type of cancer that is highly related to exposure to asbestos fibers. It shows aggressive behavior, and the current therapeutic approaches are usually insufficient to change the poor prognosis. Moreover, apart from staging and histological classification, there are no validated predictors of its response to treatment or its long-term outcomes. Numerous studies have investigated minimally invasive biomarkers in pleural fluid or blood to aid in earlier diagnosis and prognostic assessment of PM. The most studied marker in pleural effusion is mesothelin, which exhibits good specificity but low sensitivity, especially for non-epithelioid PM. Other biomarkers found in pleural fluid include fibulin-3, hyaluronan, microRNAs, and CYFRA-21.1, which have lower diagnostic capabilities but provide prognostic information and have potential roles as therapeutic targets. Serum is the most investigated matrix for biomarkers of PM. Several serum biomarkers in PM have been studied, with mesothelin, osteopontin, and fibulin-3 being the most often tested. A soluble mesothelin-related peptide (SMRP) is the only FDA-approved biomarker in patients with suspected mesothelioma. With different serum and pleural fluid cut-offs, it provides useful information on the diagnosis, prognosis, follow-up, and response to therapy in epithelioid PM. Panels combining different markers and proteomics technologies show promise in terms of improving clinical performance in the diagnosis and monitoring of mesothelioma patients. However, there is still no evidence that early detection can improve the treatment outcomes of PM patients.

Identification of Highly Sensitive Pleural Effusion Protein Biomarkers for Malignant Pleural Mesothelioma by Affinity-Based Quantitative Proteomics

Malignant pleural mesothelioma (MPM) is an asbestos-associated, highly aggressive cancer characterized by late-stage diagnosis and poor prognosis. Gold standards for diagnosis are pleural biopsy and cytology of pleural effusion (PE), both of which are limited by low sensitivity and markedly inter-observer variations. Therefore, the assessment of PE biomarkers is considered a viable and objective diagnostic tool for MPM diagnosis. We applied a novel affinity-enrichment mass spectrometry-based proteomics method for explorative analysis of pleural effusions from a prospective cohort of 84 patients referred for thoracoscopy due to clinical suspicion of MPM. Protein biomarkers with a high capability to discriminate MPM from non-MPM patients were identified, and a Random Forest algorithm was applied for building classification models. Immunohistology of pleural biopsies confirmed MPM in 40 patients and ruled out MPM in 44 patients. Proteomic analysis of pleural effusions identified panels of proteins with excellent diagnostic properties (90-100% sensitivities, 89-98% specificities, and AUC 0.97-0.99) depending on the specific protein combination. Diagnostic proteins associated with cancer growth included galactin-3 binding protein, testican-2, haptoglobin, Beta ig-h3, and protein AMBP. Moreover, we also confirmed previously reported diagnostic accuracies of the MPM markers fibulin-3 and mesothelin measured by two complementary mass spectrometry-based methods. In conclusion, a novel affinity-enrichment mass spectrometry-based proteomics identified panels of proteins in pleural effusion with extraordinary diagnostic accuracies, which are described here for the first time as biomarkers for MPM.

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 value of mesothelin in pleural fluids: comparison with CYFRA 21-1 and CEA

CYFRA 21-1 and CEA have been applied for the differential diagnosis of malignant pleural mesothelioma (MPM). The soluble mesothelin-related peptide (SMRP) has been proposed as a specific marker for distinguishing MPM from benign diseases and other malignancies in pleural effusions (PEs). In this study, we evaluated the usefulness of SMRP in PEs in the detection of mesotheliomas by comparing it with that of CYFRA 21-1, CEA, and with cytological examination. One hundred and seventy-seven consecutive patients (57 MPM, 64 metastatic tumors, and 56 benign diseases) were evaluated using commercial tests. The performance of the markers was analyzed by standard ROC analysis methods, using the area under a ROC curve (AUC) as a measure of accuracy. CYFRA 21-1 better differentiated malignant from benign effusions. The corresponding area under the receiver operating characteristic curve was 0.87, while it was 0.74 for SMRP and 0.64 for CEA (p < 0.001). Conversely, SMRP differentiated MPM from all other PEs better than both CYFRA 21-1 and CEA (AUC = 0.84, 0.76, and 0.32, respectively, p = 0.003). Low levels of CEA were associated with a MPM diagnosis. The AUC for differentiating MPM from metastases was 0.81 for SMRP, 0.61 for CYFRA 21-1, and 0.20 for CEA (p < 0.001). In cases with negative or suspicious cytology, SMRP and CYFRA 21-1 identified 36/71 and 46/66 malignant PEs (29 and 31 MPM, respectively). Only 1 MPM showed a high CEA concentration. No single marker showed the best performance in any comparison. Results suggest that SMRP could improve CYFRA 21-1 and CEA accuracy in the differential diagnosis of MPM.

Pleural fluid analysis: standstill or a work in progress?

Pleural fluid analysis yields important diagnostic information in pleural effusions in combination with clinical history, examination, and radiology. For more than 30 years, the initial and most pragmatic step in this process is to determine whether the fluid is a transudate or an exudate. Light's criteria remain the most robust in separating the transudate-exudate classification which dictates further investigations or management. Recent studies have led to the evaluation and implementation of a number of additional fluid analyses that may improve the diagnostic utility of this method. This paper discusses the current practice and future direction of pleural fluid analysis in determining the aetiology of a pleural effusion. While this has been performed for a few decades, a number of other pleural characteristics are becoming available suggesting that this diagnostic tool is indeed a work in progress.

Clinical role of pleural effusion MMP-3 levels in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive malignant tumor of mesothelial origin associated with asbestos exposure. MPM exhibits a limited response to conventional chemotherapy and radiotherapy. This, early diagnosis of MPM is essential. Malignant tumor progression requires the destruction of the basement membrane, which is constructed from extracellular matrix (ECM) materials. Various types of human tumor cells are reported to produce ECM-degrading proteases that are important in tumor progression. Among this group of proteolytic enzymes, matrix metalloproteinases (MMPs) are thought to be important due to their wide degrading function. We investigated the pleural effusion MMP-3 levels of patients with MPM and compared them with those of a population with non-malignant pleuritis or lung cancer involving malignant pleural effusion. The pleural effusion MMP-3 concentrations of 52 MPM patients and 67 non-MPM patients were measured. The results showed that the MPM patients had significantly higher pleural effusion MMP-3 levels than the population with non-malignant pleuritis. The overall survival of the MPM patients with lower pleural effusion MMP-3 levels was longer than that of patients with higher pleural effusion MMP-3 levels. Our data therefore suggest a clinical role of pleural effusion MMP-3 levels in malignant pleural mesothelioma.

Clinical significance of pleural effusion mesothelin in malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is an aggressive malignant tumor of mesothelial origin associated with asbestos exposure. MPM has a limited response to conventional chemotherapy and radiotherapy, so early diagnosis of MPM is very important. This study investigated the pleural effusion mesothelin levels in patients with MPM and compared them to those of a population with a non-malignant pleuritis or lung cancer involving malignant pleural effusion.

METHODS

The pleural effusion mesothelin concentrations were measured in 45 MPM patients and 53 non-MPM individuals (24 individuals with non-malignant pleural effusions and 29 individuals with lung cancer involving malignant pleural effusion).

RESULTS

This study demonstrated that patients with MPM had significantly higher pleural effusion mesothelin levels than a population with non-malignant pleuritis or lung cancer involving malignant pleural effusion. The difference in overall survival between the groups with pleural effusion mesothelin levels lower and higher than the assumed cut-off of 10 nM was significant.

CONCLUSIONS

The data suggest that the pleural effusion mesothelin concentration could be useful as an aid for the diagnosis of MPM.

Soluble markers for diagnosis of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive and invasive tumor, whose incidence is expected to peak, in many countries, at the end of the present decade, 20–40 years after the peak of asbestos use (asbestos being the most important etiological factor). MPM has a poor prognosis, in part, owing to a difficult and often late diagnosis hindered by a lack of available tests able to diagnose or predict this cancer in its early stages. Recently, there has been increased interest in noninvasive, economic and well-accepted diagnostic tests for screening of asbestos-exposed subjects, as well as for monitoring response of MPM patients to treatment. Several markers have been studied in biofluids, such as serum, plasma and pleural effusions, especially using ELISA, and some of them are still under investigation. However, only mesothelin and ostepontin have proven levels of sensitivity and specificity that are worth testing in the clinical setting.

Diagnostic value of Her-2/neu, Cyfra 21-1, and carcinoembryonic antigen levels in malignant pleural effusions of lung adenocarcinoma

AIMS

Cytology fails to detect neoplastic cells in 40-50% of cases of malignant pleural effusion, a condition that frequently accompanies lung adenocarcinoma. Published reports of diagnostic sensitivity of various tumour markers are inconsistent, and optimal cut-off points have not been determined. This study aimed to evaluate the ability of three markers to discriminate lung adenocarcinoma-associated malignant pleural effusion (LAC-MPE) from benign effusion.

METHODS

Pleural effusion samples were collected from 41 patients with LAC-MPE, and from 93 with various benign conditions. The diagnostic sensitivity and specificity for Her-2/neu, Cyfra 21-1, and carcinoembryonic antigen (CEA) were evaluated. Cut-off points for these markers are optimally set at 3.6 microg/L, 60 microg/L, and 6.0 microg/L, respectively.

RESULTS

Her-2/neu, Cyfra 21-1, and CEA vary in their diagnostic accuracy to differentiate LAC-MPE from benign pleural effusion: 79.85%, 88.81%, and 94.03%, respectively. CEA combined with Cyfra 21-1 increases diagnostic sensitivity to 97.6%, with a specificity of 91.4%.

CONCLUSIONS

With appropriate cut-off points, CEA currently provides the best diagnostic accuracy. Combining CEA with Cyfra 21-1 increases diagnostic sensitivity to nearly 100%. The results of the present study may help clinicians decide whether to obtain a cytological/histological specimen by invasive means to investigate a possible diagnosis of malignancy.

Assessment of Confounding Factors Affecting the Tumor Markers SMRP, CA125, and CYFRA21-1 in Serum

The purpose of this analysis was to evaluate if serum levels of potential tumor markers for the diagnosis of malignant mesothelioma and lung cancer are affected by confounding factors in a surveillance cohort of workers formerly exposed to asbestos. SMRP, CA125, and CYFRA21-1 concentrations were determined in about 1,700 serum samples from 627 workers formerly exposed to asbestos. The impact of factors that could modify the concentrations of the tumor markers was examined with linear mixed models. SMRP values increased with age 1.02-fold (95% CI 1.01–1.03) and serum creatinine concentration 1.32-fold (95% CI 1.20–1.45). Levels differed by study centers and were higher after 40 years of asbestos exposure. CA125 levels increased with longer storage of the samples. CYFRA21-1 values correlated with age 1.02-fold (95% CI 1.01–1.02), serum creatinine 1.21-fold (95% CI 1.14–1.30) and varied by study centers due to differences in sample handling. Tumor marker concentrations are influenced by subject-related factors, sample handling, and storage. These factors need to be taken into account in screening routine.

Biomarkers for malignant pleural mesothelioma: current status

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis, whose main etiology is exposure to asbestos fibers. The incidence of MPM is anticipated to increase worldwide during the first half of this century. For various reasons, MPM is difficult to diagnose and is notoriously refractory to most treatments. However, recently two active chemotherapy regimens have been demonstrated to significantly increase survival in patients with MPM, and several therapeutic agents and strategies are currently under evaluation.Researchers have actively sought MPM biomarkers for more than 20 years. Biomarkers would be helpful in managing three clinical aspects of MPM: early diagnosis, prognosis, and treatment outcome prediction. The aims of the present review are to summarize the published and recently presented data on MPM biomarkers and to identify the prospects for future translational research projects.Among the 'classical' diagnostic biomarkers measured in biological fluids, such as cytokeratins and cell surface antigens, none discriminate patients with MPM from those with other malignancies and nonmalignant diseases. Osteopontin, soluble mesothelin, and megakaryocyte potentiating factor (MPF) appear to be the most promising of the recent biomarkers, but are still subject to some limitations. Osteopontin lacks specificity for mesothelioma, while both soluble mesothelin and MPF lack sensitivity for detecting non-epithelial subtypes. Panels consisting of a small set of biomarkers do not improve the diagnostic yield, and results from molecular profiling are too preliminary to be brought into daily clinical practice. While a large number of biomarkers have been assessed in biological fluids and tumor tissue for their prognostic value, none have had a widespread impact on clinical practice. In contrast, data concerning predictive biomarkers are very limited, even though they are most interesting from the perspective of clinicians.Additional prospective studies, in large and independent samples of patients, with rigorous statistical methodology and standardized laboratory techniques are now warranted to validate and define the precise value of diagnostic and prognostic MPM biomarkers. Future research efforts should focus on biomarkers predictive of the efficacy and toxicity of standard chemotherapy. Translational research should be systematically incorporated into the design of clinical trials assessing new targeted agents in MPM.

Diagnostic value of carcinoembryonic antigen in malignant pleural effusion: a meta-analysis

BACKGROUND AND OBJECTIVE

Conventional tests are not always helpful in making a diagnosis of malignant pleural effusion (MPE). Many studies have investigated the utility of pleural carcinoembryonic antigen (CEA) in the early diagnosis of MPE. The present meta-analysis determined the accuracy of CEA measurement in the diagnosis of MPE.

METHODS

A systematic review of English language studies was conducted and data on the accuracy of pleural CEA concentrations in the diagnosis of MPE were pooled using random effects models. Receiver operating characteristic curves were used to summarize the overall test performance.

RESULTS

Forty-five studies met the inclusion criteria for the meta-analysis. The summary estimates for CEA in the diagnosis of MPE were: sensitivity 0.54 (95% CI: 0.52-0.55), specificity 0.94 (95% CI: 0.93-0.95), positive likelihood ratio 9.52 (95% CI: 6.97-13.01), negative likelihood ratio 0.49 (95% CI: 0.44-0.54) and diagnostic odds ratio 22.5 (95% CI: 15.6-32.5). Analysis of a subset of 11 studies which examined the value of pleural CEA in ruling out a diagnosis of malignant mesothelioma found that the sensitivity and specificity of a CEA level exceeding cut-off values were 0.97 (95% CI: 0.93-0.99) and 0.60 (95% CI: 0.55-0.65), respectively.

CONCLUSIONS

Measurement of pleural CEA is likely to be a useful diagnostic tool for confirming MPE, and is also helpful in the differential diagnosis between malignant pleural mesothelioma and metastatic lung cancer. The results of CEA assays should be interpreted in parallel with clinical findings and the results of conventional tests.

Soluble mesothelin in effusions: a useful tool for the diagnosis of malignant mesothelioma

BACKGROUND

The diagnosis of malignant mesothelioma is frequently difficult, the most common differential diagnosis being reactive pleural conditions and metastatic adenocarcinoma. Soluble mesothelin levels in serum have recently been shown to be highly specific and moderately sensitive for mesothelioma. As most patients with mesothelioma present with exudative effusions of either the pleura or the peritoneum, a study was undertaken to determine if levels of mesothelin were raised in these fluids and if the increased levels could help to distinguish mesothelioma from other causes of exudative effusion.

METHODS

Pleural fluid was collected from 192 patients who presented to respiratory clinics (52 with malignant mesothelioma, 56 with non-mesotheliomatous malignancies and 84 with effusions of non-neoplastic origin). Peritoneal fluid was collected from 42 patients (7 with mesothelioma, 14 with non-mesotheliomatous malignancies and 21 with benign effusions). Mesothelin levels were determined in effusion and serum samples by ELISA.

RESULTS

Significantly higher levels of mesothelin were found in effusions of patients with mesothelioma; with a specificity of 98%, the assay had a sensitivity of 67% comparing patients with mesothelioma and those with effusions of non-neoplastic origin. In 7 out of 10 cases mesothelin levels were raised in the effusion collected 3 weeks to 10 months before the diagnosis of mesothelioma was made; in 4 out of 8 of these, mesothelin levels were increased in the effusion but not in the serum.

CONCLUSIONS

Measurement of mesothelin concentrations in the pleural and/or peritoneal effusion of patients may aid in the differential diagnosis of mesothelioma in patients presenting with effusions.

Cytological diagnosis of malignant mesothelioma—improvement by additional analysis of hyaluronic acid in pleural effusions

Cytology allows the diagnosis of malignant mesothelioma (MM) from effusions with high specificity but low sensitivity. Conversely, elevated levels of hyaluronic acid (HA) in effusions are sensitive indicators of MM, although specificity is insufficient. We studied whether the cytological diagnosis of MM could be improved by HA analysis. HA was analysed in patients with histologically confirmed MM (n=162), adenocarcinoma or other malignant tumours (n=100) and in 90 patients with benign pleural diseases. In 77 out of 162 effusions, all, and in 33 some, cytological criteria of MM were satisfied. The cut-off value of HA showing maximum diagnostic reliability (86%) regarding MM was 30 mg/l (sensitivity 87%, specificity 86%). A HA value of 100 mg/l yielded 39 and 98%, respectively. Seventy three out of 77 patients with cytological findings indicative of MM showed HA levels greater than 30 mg/l as well as 27 of 33 patients with suspicious lesions. These 100 patients were correctly recognised as having MM. The addition of HA analysis to cytology, requiring all or some criteria of MM as positive, increased sensitivity for MM from 48 to 71-91%, whereas specificity only slightly decreased to 94-96%. We conclude that the combined cytological and HA analysis of pleural effusions had the potential to improve the diagnosis of MM.

Detection of numerical aberrations of chromosomes 7 and 9 in cytologic specimens of pleural malignant mesothelioma

BACKGROUND

Accurate diagnosis of malignant mesothelioma (MM) in effusion fluid specimens can be challenging. Previous cytogenetic studies demonstrated that chromosomal aneusomy is commonly associated with MM. The authors attempted to determine whether the detection of numerical chromosomal aberrations in the effusion fluid specimens could be a useful diagnostic adjunct in morphologically inconclusive cases for MM.

METHODS

The authors analyzed 17 cytologic specimens (15 pleural fluids, 2 fine-needle aspirates) of histologically confirmed MM obtained from 16 patients using fluorescent in situ hybridization (FISH) with centromeric chromosome 7 and 9 probes. Seventeen benign pleural effusion fluid specimens containing reactive/benign mesothelial (RM) cells were used as controls. After destaining of Diff-Quik-stained smears, the slides were hybridized using a standard FISH protocol. One hundred cells/probe/case were counted manually.

RESULTS

For chromosome 7, polysomy (defined as >/= 3 signals/nucleus in >10% of the cells) was present in 88% and 0% of the MM and the RM cases, respectively. Trisomy (defined as 3 signals/nucleus in > 5% of the cells) was present in 77% and 0% of the MM and the RM cases, respectively. Tetrasomy (defined as 4 signals/nucleus in > 10% of the cells) was present in 29% and 0% of the MM and the RM cases, respectively. The mean values of positive cells showing polysomy 7 and trisomy 7 were markedly different in MM and RM cases (39% vs. 4% and 31% vs. 1%, respectively). The frequency of polysomy 9 and trisomy 9 in MM and RM cases was 69% vs. 13% and 62% vs. 6%, respectively.

CONCLUSIONS

These results suggest that polysomy of chromosome 7 or 9 is a common finding in MM but uncommon in RM. Therefore, in conjunction with cytomorphologic and clinical suspicion of MM, detection of numerical chromosomal aberrations of chromosome 7 using FISH with routine cytologic smears can be a valuable diagnostic adjunct.