Assessment of interferon-γ in pleural fluid as a prognostic factor of survival in malignant pleural mesothelioma.

BACKGOUND: Literature reports suggest that the host immune system may control Malignant Pleural Mesothelioma (MPM) growth, although its activity is limited by regulatory mechanisms. In this retrospective study, we analyzed the levels of pro-inflammatory (IL-1, IL-6, TNF), immune-regulatory (IL-10) and Th1/CTL-related cytokines (IL-12p70, IFN-γ) in the pleural exudate and their relationship with overall survival (OS) in MPM. METHODS: Cytokines were quantified by multiplexed immunoassay. Concentrations were dichotomized with respect to the median value. Correlation between cytokine level and OS was assessed using univariate (Kaplan-Meier curves) and multivariate (Cox regression) analyses. RESULTS: Regarding outcome, tumor histology, therapies undergone and IFN-γ were independent prognostic factors of OS in a 72 MPM training cohort. Notably, high concentrations of IFN-γ halved death probability (HR of high vs low IFN-γ concentration = 0.491, 95%CI 0.3-0.8, p = 0.007). Also in patients with epithelioid histology and those receiving at least one line of therapy, high IFN-γ level was an independent factor predictive of OS (HR of high vs low IFN-γ concentration were 0.497, p = 0.007 and 0.324, p = 0.006, respectively). However, these data were not confirmed in a 77 MPM validation cohort, possibly due to the low IFN-γ levels encountered in this population, and the heterogeneous distribution of disease stages between the training and the validation cohorts. None of the other cytokines showed any effect on survival. CONCLUSIONS: High level of IFN-γ in pleural effusion may be associated with better survival in MPM patients and potentially serve as a prognostic biomarker. Larger prospective studies are needed to ascertain this hypothesis.

Potential role of serum mesothelin in predicting survival of patients with malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor survival rates. Therefore, it is essential to have effective biological markers predicting the course of the disease and prognosis. The aim of the present study was to highlight the prognostic significance of serum soluble mesothelin-related protein (Se-SMRP) in patients with MPM at diagnosis. Se-SMRP was determined in 60 patients using an ELISA commercial kit. Se-SMRP levels were subdivided into three tertile-based categories and in each category overall survival (OS) indexes were determined using the Kaplan-Meier and Cox regression analyses. The association between Se-SMRP levels and OS was also assessed by restricted cubic spline (RCS) analysis. No notable differences in the Kaplan-Meier probabilities were identified across the Se-SMRP categories (<0.66 nM, 0.66-1.46 nM, >1.46 nM) although an upward trend in death rate ratios (RR) was pointed out by comparing the higher (RR=1.95) and intermediate (RR=1.86) categories with the lower category (RR=1.00). In addition, such an increasing tendency, particularly when the biomarker exceeded 1.0 nM, was confirmed by an RCS function of Se-SMPR levels fitted to survival data using the Cox regression equation. The present study provided evidence in favor of a prognostic value of Se-SMRP in patients with MPM.

Characterization of soluble PD-L1 in pleural effusions of mesothelioma patients: potential implications in the immune response and prognosis.

PURPOSE: Programmed death-ligand 1 (PD-L1) protein plays a central role in the antitumor immune response, and appears to be a predictor of prognosis and efficacy for PD-L1 and programmed death 1 (PD-1) blockade therapy. The immunoregulatory role and prognostic impact of PD-L1 soluble form (sPD-L1) have been investigated in biological fluids of patients with different tumors. In malignant pleural mesothelioma (MPM), circulating sPD-L1 has been recently reported in patients' sera, but no data are available in pleural effusions (PE). In our study, we evaluated the baseline expression levels of sPD-L1 in PE from 84 MPM patients and correlated them with PD-L1-status in matched tumors and patients' overall survival (OS). METHODS: sPD-L1 in PE was determined by ELISA and tumor PD-L1 by immunohistochemistry. Association of sPD-L1 with OS was estimated using the Cox regression model. RESULTS: We observed that sPD-L1 was variably expressed in all the PE and tended to be higher (by 30%) in patients with PD-L1-positive tumors (cut-off ≥ 1% stained cells) as compared to patients with PD-L1-negative tumors (geometric mean ratio = 1.28, P value = 0.288). sPD-L1 levels were significantly higher than those of sPD-1 (P value = 0.001) regardless of the MPM histotypes and they were positively correlated (r = 0.50, P value < 0.001). Moreover, high PE sPD-L1 concentrations were associated with a trend towards increased OS (hazard ratio 0.79, 95% CL 0.62-1.01, P value = 0.062). CONCLUSIONS: Our study documents the presence of sPD-L1 in PE of MPM patients, and suggests its possible biological and prognostic role in MPM.

Determination of Mesothelin Levels in Pleural Effusion Does Not Help Predict Survival of Patients With Malignant Pleural Mesothelioma.

AIM: This study evaluated the prognostic value of soluble mesothelin-related protein (SMRP) levels in pleural effusions (PE) from patients with pleural mesothelioma (MPM). PATIENTS AND METHODS: SMRP level in PE was tested using an enzyme-linked immunosorbent assay (ELISA) in 109 patients with MPM at diagnosis before any treatment. The Kaplan-Meier method and the Cox regression were applied to compare overall survival probabilities across tertile categories of SMRP level. RESULTS: No significant differences in Kaplan-Meier overall survival probabilities among the SMRP categories were found. A statistically non-significant trend for increased death rate ratio (RR) was computed (p=0.327) when the higher (>46.5 nM, RR=1.38) and intermediate (8.5-46.5 nM, RR=1.18) SMRP categories were compared to the lower category (<8.5 nM, RR=1.00). Cox regression modelling including a restricted cubic spline showed a moderately rising non-linear trend in death rate. CONCLUSION: The SMRP level in PE does not appear to have prognostic significance and its detection is not recommended in routine clinical management of patients with MPM.

Comparison of the Diagnostic Performance of Fibulin-3 and Mesothelin in Patients with Pleural Effusions from Malignant Mesothelioma.

BACKGROUND: In the literature, there exist conflicting data on the value of fibulin-3 (FBLN3) for the diagnosis of pleural effusion (PE) in malignant pleural mesothelioma (MPM). Therefore we compared the diagnostic performance of FBLN3 against that of soluble mesothelin-related peptide (SMRP) in a cohort of Italian patients. MATERIALS AND METHODS: FBLN3 and SMRP were detected in PE from 33 patients with MPM, 64 with pleural benign lesions and 23 with non-MPM pleural metastases using a commercial enzyme-linked-immunosorbent(ELISA)-assay kit according to manufacturers' instructions. RESULTS: Levels of FBLN3 were similar in PE from MPM and PE from other pathologies (geometric mean=68.1 vs. 66.2 ng/ml; p=0.872) in contrast to SMRP levels, which were significantly higher in PE from MPM (geometric mean=14.6 vs. 3.2 nM; p<0.001). Receiver operating characteristic analysis confirmed that SMRP showed a good performance (area under the curve=0.79, p<0.001), whereas FBLN3 was not able to discriminate MPM from other pathologies (area under the curve=0.44, p=0.838). CONCLUSION: FBLN3 detection in PE, in contrast to SMRP detection, is not useful as a biomarker for the diagnosis of PE from MPM.

Role of respiratory-triggered diffusion-weighted MRI in the assessment of pleural disease.

OBJECTIVE:: To evaluate the correlation between apparent diffusion coefficient (ADC) values and histopathological features in a cohort of patients with suspected malignant pleural disease. METHODS:: We evaluated 56 consecutive patients undergoing a chest MRI examination for clinical suspicion of malignant pleural disease; all patients underwent thoracoscopic biopsy for histological assessment. All MRI examinations were performed with a 1.5-T scanner using a dedicated protocol, including a respiratory-triggered diffusion-weighted sequence with three b-values (0, 100 and 750). The ADC values were calculated, and a statistical analysis was performed. RESULTS:: The average ADC value in non-neoplastic pleural disease (NNPD) resulted in 1.84 ± 0.37 × 10-3 mm2 s-1, whereas we obtained an average value of 0.96 ± 0.19 × 10-3 mm2 s-1 in epitheliod, of 0.76 ± 0.33 × 10-3 mm2 s-1 in biphasic and of 0.67 ± 0.2 × 10-3 mm2 s-1 in sarcomatoid pleural mesotheliomas. Histology revealed the presence of malignant pleural mesothelioma (MPM) in 44 patients, chronic pleuritis in 8 patients and atypical mesothelial hyperplasia in 4 patients. Statistical analysis showed a significant difference between NNPD and MPM (p < 0.001) and between epithelioid and sarcomatoid MPM subtypes (p = 0.0004), whereas biphasic MPMs showed a wide range of overlapping with the other groups. CONCLUSION:: We observed a statistically significant difference between NNPD, epitheliod and sarcomatoid subtypes of MPM regarding ADC values. ADVANCES IN KNOWLEDGE:: Our study confirmed previous data regarding distribution of ADC values in pleural disease using a respiratory-triggered diffusion-weighted technique that allowed us to minimize motion artefacts and to reduct acquisition time.

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.

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.

Mesothelin in serum and pleural effusion in the diagnosis of malignant pleural mesothelioma with non-positive cytology.

BACKGROUND/AIM: Mesothelin (SMRP) is regarded as a biomarker of malignant pleural mesothelioma (MPM). Herein, we analyzed the contribution of SMRP detection in pleural effusion and in serum to the diagnosis of MPM with non-positive cytology. MATERIALS AND METHODS: The present study included 52 cases of MPM, 43 of pleural benign lesions and 25 of non-MPM pleural metastases. SMRP was measured by MesoMark ELISA (Cis-Bio International Gif/Yvette; France). RESULTS: In non-positive cytology, effusion-SMRP showed higher diagnostic performance than serum-SMRP. We found 38 out of 52 (73.1%) cases of non-positive cytology MPM, out of which 27 (71.0%) were positive for effusion-SMRP (cut-off=12.70 nM) and 18 (47.4%) for serum-SMRP (cut-off=1.08 nM). When cytology, effusion- and serum-SMRP were used in combination, an overall sensitivity in detection of MPM of 78.9% was achieved. The same sensitivity was obtained by combining cytology with effusion-SMRP alone, whereas the combination of serum-SMRP with cytology led to a sensitivity of 61.5%. CONCLUSION: Detection of both effusion- and serum-SMRP can contribute to improve the diagnosis of MPM with non-positive cytology. However, the analysis of SMRP in effusion makes it unnecessary to test SMRP in the serum.

Status of Anaplastic Lymphoma Kinase (ALK) in malignant mesothelioma.

BACKGROUND: Malignant mesothelioma (MM) is a particularly aggressive type of primary tumor, associated with exposure to asbestos, and characterized by high mortality. To date, there is no curative therapy for MM. The receptor anaplastic lymphoma kinase (ALK) was found to be mutated in many cases of cancer and used as a target in biological therapies. We investigated whether this pharmacological treatment could also be applicable to MM. MATERIALS AND METHODS: The state of ALK was analyzed by immunohistochemistry and fluorescent in situ hybridization in 63 MM tissue specimens. RESULTS: None of the 63 MM samples showed overexpression or translocation of ALK. CONCLUSION: Our preliminary data exclude the utility of analysis of the ALK gene in MM and suggest that ALK inhibitor therapy is not applicable to MM.

Clinical value of mesothelin in pleural effusions versus histology by medical thoracoscopy: brief report.

The aim of this study based on the third phase of the architecture of diagnostic research was to assess the sensitivity and specificity of soluble mesothelin-related peptide (SMRP) in pleural exudative effusions (PE) compared to the histology obtained by medical thoracoscopy as the diagnostic gold standard examination. We assessed 104 consecutive thoracoscopies. SMRP concentrations were obtained using an ELISA test. We had 34 mesotheliomas (25 epithelioid and 9 sarcomatoid), 35 pleural metastases, and 35 benign diseases. PE-SMRP were significantly higher in patients with epitheliomorphic mesothelioma (mean ± SD 46.55 ± 44.29 nM) than in patients with sarcomatoid mesothelioma (16.11 ± 25.02 nM; p = 0.061), pleural metastasis (7.52 ± 10.77 nM; p < 0.0001), or benign diseases (5.82 ± 8.86 nM; p < 0.0001). Using ROC curve analysis, PE-SMRP offered an AUC of 0.767 in its ability to differentiate between patients with mesothelioma and all other diagnoses. The diagnostic sensitivity and specificity of PE-SMRP for distinguishing mesothelioma from all other causes of pleural effusion, at a cut-off value of 19.6 nM, were 58.8 and 97.1 %, respectively. PE-SMRP higher than the assumed cut-off of 19.6 nM were observed in 18/25 (72.0%) epitheliomorphic mesotheliomas, 2/9 (22.2%) sarcomatoid mesotheliomas, 5/35 (14.3%) pleural metastases, and 1/35 (2.9%) benign diseases. We conclude that PE-SMRP adds some clinical information in the work-up of patients with a PE of unknown origin: (1) thoracoscopy should always be done in patients with a positive mesothelin; (2) a negative mesothelin does not exclude a malignant disease.

Mesothelin is more useful in pleural effusion than in serum in the diagnosis of pleural mesothelioma.

BACKGROUND/AIM: Soluble mesothelin-related peptide (SMRP) is regarded as a biomarker of malignant pleural mesothelioma (MPM). Herein, we compared the diagnostic performances of SMRP in matched pleural effusion (PE-SMRP) and serum (S-SMRP). MATERIALS AND METHODS: Diagnosis on pleural biopsies was performed for all patients including 43 with MPM, 23 with non-MPM pleural metastases (MTS) and 36 with benign (BNG) pleural diseases. SMRP was measured by a MesoMark ELISA (Cis-Bio International Gif/Yvette; France). RESULTS: Using the receiver operating characteristic (ROC) analysis, 12.70 and 1.08 nM were detected as cut-off values to optimal discrimination for PE-SMRP and S-SMRP, respectively. PE-SMRP showed a better diagnostic accuracy than S-SMRP in MPM vs. MTS+BNG (area under the ROC curve=81.6 vs. 70.5; sensitivity=69.8% vs. 46.5%; specificity=88.1% vs. 84.7%; diagnostic odds ratio (DOR)=17.1 vs. 4.8). In S-SMRP-negative patients, PE-SMRP maintained an acceptable performance (Sensitivity=47.8%; DOR=8.3; p=0.001), whereas in PE-SMRP-negative patients, S-SMRP performed very poorly (Sensitivity=15.4%; DOR=1.2; p=0.858). CONCLUSION: PE-SMRP detection has a superior diagnostic accuracy than S-SMRP detection in the diagnosis of MPM.

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.