Survival In Malignant Pleural Mesothelioma Research Articles

Impact of surgical intervention on overall survival in malignant pleural mesothelioma: A population-based cohort study with propensity score matching

BackgroundMalignant pleural mesothelioma (MPM) is a rare and aggressive cancer with limited treatment options. This study aims to assess the impact of surgical intervention on overall survival (OS) in patients with MPM and to identify prognostic factors influencing survival outcomes. MethodsData from the SEER-17 Database between 2000 and 2019 were analyzed. Patients were categorized into surgery and no-surgery groups. Survival analyses were conducted using Kaplan-Meier curves and Cox proportional hazards models. Propensity score matching (PSM) was applied to reduce biases. ResultsThe study included a total of 3901 MPM patients, with 1190 in the surgery group and 2711 in the no-surgery group. The median OS for the entire cohort was 10 months. The surgery group had a median OS of 15 months compared to 8 months in the no-surgery group (p < 0.001). The 1-year and 5-year OS rates for surgery patients were 56.9% and 11.2%, respectively, while for no-surgery patients, they were 34.9% and 3.7% (p < 0.001). Multivariate analysis indicated that no-surgery was an independent risk factor for worse OS (HR 1.38, 95% CI 1.21-1.39, p < 0.001). After PSM, no-surgery remained an independent risk factor influencing OS. Subgroup analysis indicated that surgery benefited most groups except those aged ≥80 years, bilateral disease, N3 stage, and certain histological grades. ConclusionSurgical intervention significantly improves survival in patients with MPM. However, benefits vary across subgroups, and careful consideration of patient-specific factors is essential.

Predicting Overall Survival for Patients with Malignant Mesothelioma Following Radiotherapy via Interpretable Machine Learning.

Malignant pleural mesothelioma (MPM) is a rare but aggressive cancer arising from the cells of the thoracic pleura with a poor prognosis. We aimed to develop a model, via interpretable machine learning (ML) methods, predicting overall survival for MPM following radiotherapy based on dosimetric metrics as well as patient characteristics. Sixty MPM (37 right, 23 left) patients treated on a Tomotherapy unit between 2013 and 2018 were retrospectively analyzed. All patients received 45 Gy (25 fractions). The multivariable Cox regression (Cox PH) model and Survival Support Vector Machine (sSVM) were applied to build predictive models of overall survival (OS) based on clinical, dosimetric, and combined variables. Significant differences in dosimetric endpoints for critical structures, i.e., the lung, heart, liver, kidney, and stomach, were observed according to target laterality. The OS was found to be insignificantly different (p = 0.18) between MPM patients who tested left- and right-sided, with 1-year OS of 77.3% and 75.0%, respectively. With Cox PH regression, considering dosimetric variables for right-sided patients alone, an increase in PTV_Min, Total_Lung_PTV_Mean, Contra_Lung_Volume, Contra_Lung_V20, Esophagus_Mean, and Heart_Volume had a greater hazard to all-cause death, while an increase in Total_Lung_PTV_V20, Contra_Lung_V5, and Esophagus_Max had a lower hazard to all-cause death. Considering clinical variables alone, males and increases in N stage had greater hazard to all-cause death; considering both clinical and dosimetric variables, increases in N stage, PTV_Mean, PTV_Min, and esophagus_Mean had greater hazard to all-cause death, while increases in T stage and Heart_V30 had lower hazard to all-cause-death. In terms of C-index, the Cox PH model and sSVM performed similarly and fairly well when considering clinical and dosimetric variables independently or jointly. Clinical and dosimetric variables may predict the overall survival of mesothelioma patients, which could guide personalized treatment planning towards a better treatment response. The identified predictors and their impact on survival offered additional value for translational application in clinical practice.

Predicting survival for patients with mesothelioma: development of the PLACE prognostic model

IntroductionThe overall survival of patients with mesothelioma is poor and heterogeneous. At present, the prediction model for Chinese patients needs to be improved. We sought to investigate predictors of survival in malignant pleural mesothelioma and develop prognostic prediction models.MethodsThis Two-center retrospective cohort study recruited patients with pathologically diagnosed mesothelioma at Beijing Chao-Yang Hospital and Beijing Tong-Ren Hospital. We developed a new prognostic prediction model based on COX multivariable analysis using data from patients who were recruited from June 1, 2010 to July 1, 2021 in Beijing Chao-Yang Hospital (n = 95, development cohort) and validated this model using data from patients recruited from July 18, 2014 to May 9, 2022 in Beijing Tong-Ren Hospital (n = 23, validation cohort). Receiver operating characteristic analysis was used to estimate model accuracy.ResultsThe parameters in this new model included PLT > 289.5(10^9/L) (1 point), Lymphocyte > 1.785(10^9/L) (-1point), Age > 73 years old (1 point), Calcium > 2.145(mmol/L) (-1point), Eastern Cooperative Oncology Group performance status (ECOG PS) > 2 (2 points). When the sum of scores < 0, it is recognized as a low-risk group; when the score is 0 ~ 3, it is recognized as a high-risk group. The survival rate of patients in the high-risk group was significantly lower than that in the low-risk group (hazard ratio [HR], 3.878; 95% confidence interval [CI], 2.226–6.755; P < 0.001). The validation group had similar results (HR,3.574; 95%CI,1.064–12.001; P = 0.039). Furthermore, the areas under the curve 6 months after diagnosis in the two cohorts were 0.900 (95% CI: 0.839–0.962) and 0.761 (95% CI: 0.568–0.954) for development and validation cohorts, respectively.ConclusionWe developed a simple, clinically relevant prognostic prediction model for PLACE by evaluating five variables routinely tested at the time of diagnosis. The predictive model can differentiate patients of Chinese ethnicity into different risk groups and further guide prognosis.

48 - The Scottish Mesothelioma Network: impact of a national multidisciplinary team on overall survival in malignant pleural mesothelioma

48 - The Scottish Mesothelioma Network: impact of a national multidisciplinary team on overall survival in malignant pleural mesothelioma

Factors affecting the life expectancy in malignant pleural mesothelioma: Our 10 years of studies and experience.

Malignant pleural mesothelioma (MPM) is an aggressive tumor with a poor prognosis. In our study, we aimed to investigate the specific clinical, laboratory, and radiological features of the tumor and the prognostic effect of SUVmax (maximum standardized uptake values) according to PET/CT (positron emission tomography). Demographic, therapeutic, clinical, and survival information of patients diagnosed with histologically-validated pleural mesothelioma in our hospital between January 2010 to December 2019 will be retrospectively scanned from the hospital records. A total of 116 patients, 61 men (52.6%), and 55 women (47.4%), were analyzed. Thirty five patients (30.2%) were over the age of 65. Percentage of patients over 65 years of age, neutrophil count, and PET SUV Max values, asbestos exposure and pleural thickening rate were significantly higher in the deceased patients’ group than in the living patients’ group (P = .042, P = .039, P = .002, P = .004, P = .037). T stage (tumor stage), N stage (lymph nodes stage), metastasis stage, and Grade distribution were significantly higher in the deceased patients’ group than in the living patients’ group (P < .000, P < .000, P = .003, P < .000). The rates of chemotherapy and surgical treatment, right lung location, and epithelioid pathology were significantly lower in the deceased patients’ group compared to the living patients’ group (P = .016, P = .030, P = .018, P = .008). The mean follow-up time was 13 months. Key determinants of survival in MPM include age, male gender, neutrophil increase, pleural thickening, high PET SUV max values, stage, histological type, asbestos exposure, and treatment regimen.

Positive impact of academic center care on overall survival in malignant pleural mesothelioma (MPM): A National Cancer Database (NCDB) socioeconomic factor analysis.

8558 Background: MPM is a rare cancer with a poor prognosis. Median survival for untreated patients is 4-13 months, and for treated patients is 6-18 months. Despite asbestos regulations in the United States, annual deaths from MPM rose from 2,479 in 1999 to 2,597 in 2015. Given recent treatment advances, including improvements in multimodality therapy and the introduction of immunotherapy as a treatment option in the frontline setting, the impact that patient demographics and treatment factors have on survival outcomes for MPM requires further evaluation. Methods: We identified all patients with MPM in the NCDB from 2004 to 2017. Differences in demographic, disease, and treatment characteristics were assessed by year of diagnosis using Chi-square test. The effect of age, race, insurance status, income, distance to treatment center, and education level on overall survival (OS) was assessed by log-rank test. Results: There were 15,287 MPM diagnoses in the NCDB between 2004-2010 and 17,059 diagnoses between 2011-2017. OS improved between the two time periods, with median OS of 9.46 months (95% CI: 9.23-9.63) and 5-year OS rate of 8.3% (95% CI: 7.9-8.7%) in patients from 2004-2011 and median OS of 11.33 months (95% CI: 11.01-11.7) and 5-year OS rate of 12.4% (95% CI: 11.8-13.1%) in patients after 2011, despite an increase in stage IV disease in the latter group. Older patients (≥65 years-old), males, patients with stage IV disease, patients with government primary payer insurance, and patients from urban areas all had significantly worse OS. Patients without comorbidities and those treated at an academic center had significantly better OS. OS was found to significantly increase as both income and education level increase. Patients diagnosed after 2011 were significantly older, were more frequently female, had more stage IV disease, were more frequently treated at academic centers, more commonly had government primary payer insurance, and lived significantly further away from their treatment center. Patients’ time to treatment was significantly increased after 2011 (from 28 to 31 days). Conclusions: Socioeconomic factors play an important role in survival outcomes for patients with MPM. Many of these are linked with access to healthcare resources, which may increase the likelihood of evaluation at academic centers. For a rare malignancy such as mesothelioma, subspecialty care consisting of a comprehensive thoracic surgical evaluation and appropriate multimodality treatment are of great importance. Time to treatment increased during the study period yet OS improved, which our findings suggest are a result of an increase in evaluation and treatment at academic centers by providers skilled in delivering care to MPM patients.

Incidence, mortality and survival in malignant pleural mesothelioma before and after asbestos in Denmark, Finland, Norway and Sweden

BackgroundMalignant pleural mesothelioma (MPM) is a rare but fatal cancer, which is largely caused by exposure to asbestos. Reliable information about the incidence of MPM prior the influence of asbestos is lacking. The nationwide regional incidence trends for MPM remain poorly characterized. We use nationwide MPM data for Denmark (DK), Finland (FI), Norway (NO) and Sweden (SE) to assess incidence, mortality and survival trends for MPM in these countries.MethodsWe use the NORDCAN database for the analyses: incidence data were available from 1943 in DK, 1953 in FI and NO and 1958 in SE, through 2016. Survival data were available from 1967 through 2016. World standard population was used in age standardization.ResultsThe lowest incidence that we recorded for MPM was 0.02/100,000 for NO women and 0.05/100,000 for FI men in 1953–57, marking the incidence before the influence of asbestos. The highest rate of 1.9/100,000 was recorded for DK in 1997. Female incidence was much lower than male incidence. In each country, the male incidence trend for MPM culminated, first in SE around 1990. The regional incidence trends matched with earlier asbestos-related industrial activity, shipbuilding in FI and SE, cement manufacturing and shipbuilding in DK and seafaring in NO. Relative 1-year survival increased from about 20 to 50% but 5-year survival remained at or below 10%.ConclusionIn the Nordic countries, the male incidence trends for MPM climaxed and started to decrease, indicating that the prevention of exposure was beneficial. Survival in MPM has improved for both sexes but long-term survival remains dismal.

Multivariate Model for Predicting Overall Survival in Malignant Pleural Mesothelioma After Adjuvant Radiotherapy

<h3>Purpose/Objective(s)</h3> Malignant pleural mesothelioma (MPM) is a rare but aggressive cancer arising from the cells of the thoracic pleura. Its anatomic complexity, large surface area, and unique location pose challenges for target coverage while sparing adjacent organs at risk (OARs) during treatment planning for adjuvant radiotherapy after pleurectomy and decortication. We aimed to investigate the associations between patient/target characteristics and achievable dosimetric plan quality with overall survival. <h3>Materials/Methods</h3> Sixty patients with MPM patients who were treated on a tomotherapy unit between 2013-2018 at a single institution were included. All patients received helical IMRT with 45 Gy/25 fractions. Dosimetric quantities for the lungs, heart, and liver were systematically examined for 37 right-sided (RSM) and 23 left-sided mesothelioma (LSM) patients. Patient characteristics and/or planning dosimetric metrics were input into machine learning algorithms, e.g., LASSO regression, support vector machine (SVM), and multiple layer perceptron (MLP), in order to construct predictive models for overall survival. The performance of predictive models was evaluated with area under the curve (AUC) using 3-fold cross validation. Normal tissue complication probabilities (NTCP) for selected OARs were estimated using the Lyman-Kutcher-Burman model based on individual dose volume histograms. <h3>Results</h3> The achieved dosimetric endpoints were significantly different (<b>P</b> < 0.05) between LSM vs. RSM patients, respectively: ipsilateral lung V20_Gy of 91.2 ± 6.7 vs. 85.3 ± 6.5%, ipsilateral mean lung doses of 39.1 ± 3.8 vs. 36.9 ± 2.5 Gy, heart mean doses of 25.2 ± 3.6 vs. 18.8 ± 3.7 Gy, and liver mean doses of 10.6 ± 2.7 vs. 23.4 ± 4.2 Gy. There was no significant difference in total lung – planning target volume (PTV) mean dose, 13.4 ± 2.0 vs. 14.4 ± 1.5 Gy, nor expected lung pneumonitis for the LSM vs. RSM. No differences were observed between PTV coverage of 94.2 ± 1.2 vs. 93.4 ± 2.4%, and average survival intervals were 16.8 ± 14.4 months and 18.0 ± 18.0 months after RT between LSM vs. RSM. The MLP model achieved AUCs of 0.65, 0.67 and 0.71 using patient characteristics, dosimetric features, and combined features. The identified predictors most associated with overall survival were age, PTV volume, ipsilateral lung volume/V20_Gy, and ipsilateral lung – PTV V20_Gy <h3>Conclusion</h3> We demonstrated correlations between patient specific characteristics and achieved planning dosimetric parameters for left- and right-sided MPM treatment planning endpoints. Combining patient characteristics and dosimetric endpoints, the multivariate predictive model achieved decent performance in predicting overall survival. The predictive model may guide treatment planning to achieve optimal planning dosimetry, and to improve clinical outcome via personalized treatment for MPM.

OA13.03 Type M1 and Type M2 Macrophages Are Associated With Patient Survival in Malignant Pleural Mesothelioma

Previous studies have demonstrated the prognostic role of the immunological tumor microenvironment in malignant pleural mesothelioma (MPM). Tumor-infiltrating macrophages form the major component of the leucocytes in MPM tumor microenvironment. Macrophages can be divided into two main phenotypes: type M1 macrophages have an anti-tumorigenic function and type M2 macrophages a pro-tumorigenic function promoting tumor development. The macrophage phenotypes affect the biological behavior of MPM and may provide potential therapeutic targets.

Pre-Clinical Research Advancements Relating to Improving the Diagnosis and Treatment of Malignant Pleural Mesothelioma: A Review

Malignant pleural mesothelioma (MPM) is a rare, aggressive cancer of the lung lining that is predominantly associated with occupational exposure to asbestos. MPM is responsible for thousands of deaths worldwide every year, with the median survival of MPM of 8–14 months. There are limited biomarkers available in the clinic to effectively diagnose MPM, an invasive biopsy procedure is usually required to provide a definitive diagnosis. Due to the long latency period associated with MPM disease presentation, the cancer is usually at an advanced stage at the time of diagnosis where treatment options are largely ineffective at controlling disease progression. Previous MPM-based pre-clinical studies have made significant strides in determining the exact molecular mechanisms associated with asbestos carcinogenesis. Exploring less invasive blood-based biomarkers and treatment strategies involving targeted therapy, immunotherapy, and virotherapy is particularly important. Research in these areas is of crucial importance in relation to improving the rate of novel diagnostic biomarkers and treatment strategies progressing through to clinical trials and ultimately into the clinical setting. This review comprehensively summarises both previous and current pre-clinical research developments that have specifically contributed to an improved understanding of MPM disease biology, and the development of novel diagnostic biomarkers and treatment strategies.

High Expression of PEA15 Is Associated With Patient Survival in Malignant Pleural Mesothelioma.

Malignant pleural mesothelioma (MPM) is a rare but very aggressive tumor that is primarily pleural in origin. The 5-year overall survival rate of patients with MPM has not improved despite therapeutic advances. Therefore, biomarker discovery to identify premalignant or early malignant tumors of the mesothelium are crucial. PEA15 is a cytoplasmic protein that is involved in various human malignancies, including MPM. However, the clinicopathological involvement of PEA15 in MPM has not yet been documented. The Oncomine database and GEPIA2 platform were used to analyze PEA15 mRNA expression and patient survival in patients with MPM. PEA15 was found to be significantly up-regulated in MPM, and this up-regulation inversely correlated with prolonged patient survival. Further, PEA15 expression was found to be increased in other cancer tissues without affecting overall survival. PEA15 may represent a new potential prognostic biomarker in MPM patients.

1736P Prognostic factors predicting survival in malignant pleural mesothelioma: A retrospective study in two Spanish hospitals

Malignant pleural mesothelioma (MPM) is a rare, aggressive tumor, with poor prognosis. Its well-known association to asbestos exposure helps to identify the population mostly affected by this disease. The aim of this study is to characterize patients with MPM in two Spanish hospitals, as well as define prognostic variables which may influence outcomes and survival.

The Association Between Pleural Fluid Exposure and Survival in Pleural Mesothelioma

Most patients with malignant pleural mesothelioma (MPM) seek treatment with malignant pleural effusion (MPE). Invitro evidence suggests that MPE may not be a simple bystander of malignancy, but rather potentially has biological properties that improve cancer cell survival and promote cancer progression. If this is the case, MPE management may need to shift from current symptomatic strategies to aggressive fluid removal to impact survival. Is there an association between pleural fluid exposure and survival in MPM? Data from 761 patients who received a diagnosis of MPM between 2008 and 2018 were collected from patient medical records in three UK pleural units. Data included factors previously identified as influencing prognosis in MPM. Medical imaging was reviewed for presence, size, and duration of pleural effusion. Time-dependent covariate analysis of pleural fluid exposure and survival (model included weight loss, serum albumin, hemoglobin, MPM subtype, performance status, chemotherapy, and age) and multivariate Cox regression analysis of pleurodesis and survival were conducted. Median overall survival was 278days (interquartile range, 127-505days; 95%CI, 253-301days). Pleural fluid exposure duration showed no association with survival (hazard ratio, 1.0; 95%CI, 1.0-1.0). Median survival was 473, 378, and 258days with complete, partial, and no pleurodesis (P= .008). Pleurodesis success seems to be associated with improved survival; however, it is unclear whether duration of MPM exposure to pleural fluid is associated with survival within the limitations of this retrospective study. Future prospective studies are required to assess this potentially important mechanism.

A narrative review of the health disparities associated with malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is a cancer of the mesothelial lining of the pleura that has traditionally been associated with asbestos exposure in an industrial setting. Asbestos usage has fortunately been banned or phased out in most industrialized countries resulting in its decline in countries such as the United States. Despite this, MPM continues to place significant burden on its affected patients resulting in overall poor prognosis and survival. Questions arise as to what factors, especially what health disparities, contribute to the disease’s dismal prognosis. This article will present a narrative review of recent literature that identifies the impact age, sex, race, access to medical centers, and economics have on the diagnosis, treatment, and prognosis of MPM. As will be discussed, research has shown that factors including younger age, female sex, non-white race, private insurance, Medicare, and higher income have been associated with better survival in MPM. Whereas older age, male sex, white race, lack of insurance, and lower income are associated with worse survival. The identification of these and other health disparities related to MPM may allow for future research, clinical guidelines, and policies to be implemented to decrease the burden health disparities create in the diagnosis, treatment, and prognosis of patients with MPM.

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

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. 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. 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. 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.

Clinical prognostic factors in pleural mesothelioma: best supportive care and anti-tumor treatments in a real-life setting

Background This study aims to investigate patient- and disease characteristics associated with survival in malignant pleural mesothelioma (MPM) patients with anti-tumor treatment or with best supportive care (BSC). Materials and methods Consecutive MPM cases diagnosed in North Denmark Region from 1972 to 2015 were reevaluated and verified by two pathologists using modern immunohistochemical techniques. Danish registries and hospital records were used to gather patient-, asbestos exposure-, and disease information. Results Of the 279 patients, anti-tumor treatment was administered to 184 patients (66.0%). All of those received chemotherapy alone or as part of a multimodal treatment, where pemetrexed was given to 126 (68.5%) patients. Asbestos exposure was documented in 92.5% of all patients. In the treated group, mean age was lower (66 years versus 74 years, p < 0.01), rate of occupational asbestos exposure was higher (74.5 versus 54.7%, p < 0.01), more patients had better performance score (98.4 versus 60%, p < 0.01) and stage was lower (81 versus 63.2%, p < 0.01) compared to the BSC group. Multivariate analysis showed that epithelioid subtype was the only common prognostic factor for OS in both groups. In BSC patients, good PS and female gender was associated with improved OS. Median overall survival (OS) was 17 versus 4 months (p < 0.01), and independently of the histopathological subtype, the median and 2-year survival was higher in the treated versus the BSC group (p < 0.02). Conclusions This retrospective study showed that epithelioid subtype is the only independent positive prognostic factor of survival in treated patients with MPM. For BSC patients, the epithelioid subtype, good PS, and female gender were positive prognostic factors, while age and comorbidities were not significant. This study with long-term follow-up of treated and BSC MPM patients can contribute to the clinical stratification of patients. Further validation is appropriate to verify these findings.

Predicting survival in malignant pleural mesothelioma using routine clinical and laboratory characteristics

IntroductionThe prognosis of malignant pleural mesothelioma (MPM) is poor, with a median survival of 8–12 months. The ability to predict prognosis in MPM would help clinicians to make informed decisions...

First-line nivolumab plus ipilimumab in unresectable malignant pleural mesothelioma (CheckMate 743): a multicentre, randomised, open-label, phase 3 trial

Approved systemic treatments for malignant pleural mesothelioma (MPM) have been limited to chemotherapy regimens that have moderate survival benefit with poor outcomes. Nivolumab plus ipilimumab has shown clinical benefit in other tumour types, including first-line non-small-cell lung cancer. We hypothesised that this regimen would improve overall survival in MPM. This open-label, randomised, phase 3 study (CheckMate 743) was run at 103 hospitals across 21 countries. Eligible individuals were aged 18 years and older, with previously untreated, histologically confirmed unresectable MPM, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Eligible participants were randomly assigned (1:1) to nivolumab (3 mg/kg intravenously once every 2 weeks) plus ipilimumab (1 mg/kg intravenously once every 6 weeks) for up to 2 years, or platinum plus pemetrexed chemotherapy (pemetrexed [500 mg/m2 intravenously] plus cisplatin [75 mg/m2 intravenously] or carboplatin [area under the concentration-time curve 5 mg/mL per min intravenously]) once every 3 weeks for up to six cycles. The primary endpoint was overall survival among all participants randomly assigned to treatment, and safety was assessed in all participants who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT02899299, and is closed to accrual. Between Nov 29, 2016, and April 28, 2018, 713 patients were enrolled, of whom 605 were randomly assigned to either nivolumab plus ipilimumab (n=303) or chemotherapy (n=302). 467 (77%) of 605 participants were male and median age was 69 years (IQR 64-75). At the prespecified interim analysis (database lock April 3, 2020; median follow-up of 29·7 months [IQR 26·7-32·9]), nivolumab plus ipilimumab significantly extended overall survival versus chemotherapy (median overall survival 18·1 months [95% CI 16·8-21·4] vs 14·1 months [12·4-16·2]; hazard ratio 0·74 [96·6% CI 0·60-0·91]; p=0·0020). 2-year overall survival rates were 41% (95% CI 35·1-46·5) in the nivolumab plus ipilimumab group and 27% (21·9-32·4) in the chemotherapy group. Grade 3-4 treatment-related adverse events were reported in 91 (30%) of 300 patients treated with nivolumab plus ipilimumab and 91 (32%) of 284 treated with chemotherapy. Three (1%) treatment-related deaths occurred in the nivolumab plus ipilimumab group (pneumonitis, encephalitis, and heart failure) and one (<1%) in the chemotherapy group (myelosuppression). Nivolumab plus ipilimumab provided significant and clinically meaningful improvements in overall survival versus standard-of-care chemotherapy, supporting the use of this first-in-class regimen that has been approved in the USA as of October, 2020, for previously untreated unresectable MPM. Bristol Myers Squibb.

Diagnostic Laparoscopy Improves Staging of Malignant Pleural Mesothelioma With Routine Positron Emission Tomography Imaging

With a multimodal treatment strategy, cytoreductive surgery extends survival in malignant pleural mesothelioma. Improving the accuracy of staging can refine patient selection. Our objective was to determine whether diagnostic laparoscopy (DL) improves staging for patients with malignant pleural mesothelioma with the routine use of positron emission tomography (PET). We performed a retrospective review of our prospectively maintained database from February 2014 to May 2019. Inclusion criteria were patients who had disease in the chest that was deemed potentially resectable by radiographic criteria and who underwent DL as part of the staging evaluation before surgery. Of 187 patients (71% men, 80% epithelial) who underwent DL during staging, 76% proceeded to surgery; 22% were unresectable at exploratory thoracotomy and 78% underwent resection (pleurectomy and decortication, 68%; extrapleural pneumonectomy, 32%). Also, 89% had a PET computed tomography (CT), and 11% had a preoperative CT without PET. DL revealed peritoneal disease in 17%. Among patients with pathologically proven disease at DL, 77% had negative PET-CT imaging. Based on the pathologic findings at DL the sensitivity, specificity, positive predictive value, and negative predictive value of PET-CT were 23%, 78%, 17%, and 83%, respectively. The accuracy of PET-CT was 68%. PET-CT has low sensitivity and diagnostic accuracy to identify peritoneal disease in malignant pleural mesothelioma. DL as part of the preoperative staging defines an important subset of patients with bicavitary disease. We recommend DL as a component of staging before surgery.

Prognostic Role of Programmed Cell Death 1 Ligand 1 in Resectable Pleural Mesothelioma

The prognostic role of programmed cell death 1 ligand 1 (PD-L1) in malignant pleural mesothelioma (MPM) is incompletely understood. Our objectives were to evaluate the evidence for tumor PD-L1 as a prognostic biomarker in MPM through meta-analysis and to determine whether tumor PD-L1 expression is associated with survival in MPM patients undergoing macroscopic complete resection. Meta-analysis was performed to determine the association of PD-L1 with overall survival in MPM (n= 1655) from 14 studies containing overall survival and tumor PD-L1 expression. Univariable and multivariable analyses tested the relationship of tumor PD-L1 with overall survival and recurrence-free survival in an institutional cohort of MPM patients treated by macroscopic complete resection (n= 75). To validate the association of PD-L1 with overall survival, we utilized two independent MPM cohorts (n= 284). Meta-analysis demonstrated that high tumor PD-L1 expression was associated with poor overall survival. Among 75 patients undergoing macroscopic complete resection, 49 tumors (65%) expressed PD-L1 (1% or more), and high PD-L1 (50% or greater) was more commonly expressed on nonepithelial (29%) compared with epithelial tumors (14%). High tumor PD-L1 expression was independently associated with poor overall survival (P < .001, hazard ratio 5.67) and recurrence-free survival (P= .003, hazard ratio 3.28). The association of PD-L1 overexpression with unfavorable survival was more significant in epithelial MPMs than nonepithelial MPMs. These findings were validated in RNA sequencing analyses in two independent cohorts. Exploratory transcriptome analysis revealed that MPM tumors with PD-L1 overexpression displayed coexpression of other immune regulatory molecules, programmed cell death 1 ligand 2 and T-cell immunoglobulin mucin receptor3. Tumor PD-L1 expression is a prognostic biomarker in patients undergoing surgical resection for MPM and may be useful in perioperative decision making.