Clinical investigation of former workers exposed to asbestos: the health surveillance experience of an Italian University Hospital.

Background: The need for health surveillance of former workers exposed to asbestos was provided by law in Italy after the asbestos ban in 1992. Objectives: We describe the results of the health surveillance of former workers exposed to asbestos, conducted over 27 years, from 1994 to 2020, at the Operative Unit of Occupational Medicine of the University Hospital of Bari. Materials and methods: We adopted the health surveillance protocol, which was validated at the national level in 2018. Results: A total of 1,405 former workers exposed to asbestos were examined. We proceeded with diagnosing pathologies in 339 cases (24% of the cohort subjected to surveillance), with diagnoses of some cases involving multiple pathologies. Specifically, pleural plaques were diagnosed in 49.2% of the 339 cases, asbestosis in 35.9%, malignant pleural mesothelioma (MPM) in 20.3%, mesothelioma of the vaginal tunic of the testis (MTVT) in 9.1%, lung cancer in 5.8%, and laryngeal cancer in 0.8%. Conclusion: Despite the 1992 asbestos ban, asbestos-related diseases remain a serious public health issue. It is important to establish criteria that ensure the health surveillance of formerly exposed workers minimizes costs, reduces the number of invasive examinations, and optimizes achievable results.

Living with mesothelioma: a systematic review of mental health and well-being impacts and interventions for patients and their informal carers.

OBJECTIVES: Mesothelioma is an aggressive cancer predominantly affecting the lung and abdominal linings. It can have a unique impact on mental health and well-being (MHWB) due to its incurability, poor prognosis and asbestos-exposure causation. This review's aims were to identify/synthesise international evidence on mesothelioma's MHWB impacts; explore MHWB interventions used by patients and carers; and identify evidence of their effectiveness. DESIGN: Systematic review. DATA SOURCES: Databases, searched March 2022 and March 2024, were MEDLINE; CINAHL; PsycINFO; Cochrane Library; ASSIA. ELIGIBILITY CRITERIA: We included study designs focusing on psychological impacts of living with mesothelioma and MHWB interventions used by patients and informal carers, published in English since January 2002. DATA EXTRACTION AND SYNTHESIS: A team of reviewers screened included studies using standardised methods. Quality was assessed using validated tools: Mixed-Methods Appraisal tool for primary research and Joanna Briggs Institute Critical Appraisal Checklist for Systematic Reviews. RESULTS: Forty-eight studies met the inclusion criteria: 20 qualitative, 16 quantitative, nine reviews, two mixed-methods, one combined systematic review/qualitative study. UK studies predominated. Many MHWB impacts were reported, including traumatic stress, depression, anxiety and guilt. These were influenced by mesothelioma's causation, communication issues and carer-patient relational interactions. Participants used wide-ranging MHWB interventions, including religious/spiritual practice; talking to mental-health professionals; meaning-making. Some strategies were presented as unhelpful, for example, denial. Participants reported lack of access to support. CONCLUSIONS: Most qualitative studies were rated high quality. The quality of the quantitative studies and reviews varied. The sparse literature regarding MHWB in mesothelioma means more research is needed into impacts on patients and carers, including trauma. To enable access to evidence-based support, research is recommended concerning MHWB interventions' effectiveness in mesothelioma. PROSPERO REGISTRATION NUMBER: CRD42022302187.

Germline BARD1 variants predispose to mesothelioma by impairing DNA repair and calcium signaling.

We report that ~1.8% of all mesothelioma patients and 4.9% of those younger than 55, carry rare germline variants of the BRCA1 associated RING domain 1 (BARD1) gene that were predicted to be damaging by computational analyses. We conducted functional assays, essential for accurate interpretation of missense variants, in primary fibroblasts that we established in tissue culture from a patient carrying the heterozygous BARD1V523A mutation. We found that these cells had genomic instability, reduced DNA repair, and impaired apoptosis. Investigating the underlying signaling pathways, we found that BARD1 forms a trimeric protein complex with p53 and SERCA2 that regulates calcium signaling and apoptosis. We validated these findings in BARD1-silenced primary human mesothelial cells exposed to asbestos. Our study elucidated mechanisms of BARD1 activity and revealed that heterozygous germline BARD1 mutations favor the development of mesothelioma and increase the susceptibility to asbestos carcinogenesis. These mesotheliomas are significantly less aggressive compared to mesotheliomas in asbestos workers.

Incidental Diagnosis of Malignant Peritoneal Mesothelioma During Liver Transplantation Surgery: A Case Report.

BACKGROUND Malignant peritoneal mesothelioma (MPM) is a rare, lethal tumor of serous membranes. The most common factor reported in association with MPM is asbestos exposure, while viral infections, genetic predisposition, paraneoplastic syndrome, and altered immunity have been described as well. The diagnosis can be challenging among those with lower tumor burden as well as nonspecific symptoms, and it is not unusual to discover the diagnosis incidentally. CASE REPORT A middle-aged woman with decompensated cirrhosis underwent extensive pre-transplant workup, showing no evidence of malignancy. She had a personal history of asbestos exposure and family history of MPM in the extended family. During transplant surgery, a few peritoneal nodules were noted, leading to termination of the procedure. Pathological analysis confirmed malignant MPM. A multidisciplinary discussion led to following a conservative treatment approach without any intervention, due to higher risk of worsening hepatic decompensation associated with peritonectomy and intraperitoneal chemotherapy. The patient's hepatic decompensation resolved 6 months after the aborted liver transplant operation. Since the diagnosis of MPM, positron emission tomography scans have shown no recurrence of MPM for 3 consecutive years. CONCLUSIONS This is the first case of MPM diagnosed incidentally during a liver transplantation surgery. This case highlights the challenges in the diagnosis and management of MPM in a patient with decompensated liver disease. A multidisciplinary approach and following a consensus decision led to prolonged survival in the described patient.

Integration of the PD-L1 inhibitor atezolizumab and WT1/DC vaccination into standard-of-care first-line treatment for patients with epithelioid malignant pleural mesothelioma-Protocol of the Immuno-MESODEC study.

Malignant pleural mesothelioma (MPM) is an aggressive cancer with a very poor prognosis. Recently, immune checkpoint inhibition (ICI) has taken center stage in the currently ongoing revolution that is changing standard-of-care treatment for several malignancies, including MPM. As multiple arguments and accumulating lines of evidence are in support of the existence of a therapeutic synergism between chemotherapy and immunotherapy, as well as between different classes of immunotherapeutics, we designed a multicenter, single-arm, phase I/II trial in which both programmed-death-ligand 1 (PD-L1) inhibition and dendritic cell (DC) vaccination are integrated in the first-line conventional platinum/pemetrexed-based treatment scheme for epithelioid MPM patients (Immuno-MESODEC, ClinicalTrials.gov identifier NCT05765084). Fifteen treatment-naïve patients with unresectable epithelioid subtype MPM will be treated with four 3-weekly (±3 days) chemo-immunotherapy cycles. Standard-of-care chemotherapy consisting of cisplatinum (75mg/m2) and pemetrexed (500mg/m2) will be supplemented with the anti-PD-L1 antibody atezolizumab (1200 mg) and autologous Wilms' tumor 1 mRNA-electroporated dendritic cell (WT1/DC) vaccination (8-10 x 106 cells/vaccination). Additional atezolizumab (1680 mg) doses and/or WT1/DC vaccinations (8-10 x 106 cells/vaccination) can be administered optionally following completion of the chemo-immunotherapy scheme. Follow-up of patients will last for up to 90 days after final atezolizumab administration and/or WT1/DC vaccination or 24 months after diagnosis, whichever occurs later. The trial's primary endpoints are safety and feasibility, secondary endpoints are clinical efficacy and immunogenicity. This phase I/II trial will evaluate whether addition of atezolizumab and WT1/DC vaccination to frontline standard-of-care chemotherapy for the treatment of epithelioid MPM is feasible and safe. If so, this novel combination strategy should be further investigated as a promising advanced treatment option for this hard-to-treat cancer.

[Advances in Targeted Therapy for Malignant Pleural Mesothelioma].

Malignant pleural mesothelioma (MPM) is a rare cancer with high malignancy and aggressiveness on the pleural, caused by the following risk factors including asbestos inhalation, genetic factors, and genetic mutation. The present chemotherapy, antiangiogenic therapy, and immunotherapy methods are ineffective and the survival time of patients is very short. There is an urgent need to find potential therapeutic targets for MPM. At present, it has been found the following types of targets: gene mutation targets such as BRCA associated protein 1 (BAP1) and cyclin-dependent kinase 2A (CDKN2A); epigenetic targets such as lysine (K)-specific demethylase 4A (KDM4A) and lysine-specific demethylase 1 (LSD1), and signal protein targets such as glucose-regulated protein 78 (GRP78) and signal transducer and activator of transcription 3 (STAT3). So far, available clinical trials include phase II clinical trials of histone methyltransferase inhibitor Tazemetostat, poly (ADP-ribose) polymerase (PARP) inhibitor Rucaparib and cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor Abemaciclib, as well as phase I clinical trials of mesothelin-targeting chimeric antigen receptor T-cell immunotherapy (CAR-T) cell injection in the thoracic cavity and TEA domain family member (TEAD) inhibitor VT3989 and IK-930, and the results of these trials have showed certain clinical efficacy.
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Confirmatory validation of the Mesothelioma Psychological Distress Tool-Patients: A brief patient-reported outcome measure assessing psychological distress in malignant mesothelioma patients.

OBJECTIVE: Psychological suffering in patients with Malignant Mesothelioma (MM) is different from the one experienced by patients with other cancers due to its occupational or environmental etiology and its peculiar symptomatology and prognosis (i.e., poor prognosis, reduced effectiveness of the therapies, poor quality of residual life, and advanced age at the time of diagnosis). Therefore, the Mesothelioma Psychological Distress Tool-Patients (MPDT-P) has been developed to evaluate the specific profile of psychological suffering in this population. This paper describes the item selection, factor analysis, and psychometric evaluation of the revised MPDT-P. METHODS: The analyses of the current work aimed to confirm the factorial structure found in the first version of the MPDT-P. In the case of nonfit, it aimed to find an alternative structure and causes of nonfit in the model. The search for the fit of the factorial model was conducted using a Bayesian approach. RESULTS: The two-factor model reported in the first version of the instrument did not fit the data. Confirmatory Bayesian analyses showed adequate fit for the three-factor solution. Based on the content of the items, we labeled the factors as dysfunctional emotions, claims for justice, and anxieties about the future. CONCLUSIONS: Integrating the MPDT-P into clinical practice could help clinicians gain insight into the specific suffering related to MM and investigate potential differences related to different occupational and environmental exposure contexts.

Imaging in pleural Mesothelioma: A review of the 16th International Conference of the International Mesothelioma Interest Group.

Imaging continues to gain a greater role in the assessment and clinical management of patients with mesothelioma. This communication summarizes the oral presentations from the imaging session at the 2023 International Conference of the International Mesothelioma Interest Group (iMig), which was held in Lille, France from June 26 to 28, 2023. Topics at this session included an overview of best practices for clinical imaging of mesothelioma as reported by an iMig consensus panel, emerging imaging techniques for surgical planning, radiologic assessment of malignant pleural effusion, a radiomics-based transfer learning model to predict patient response to treatment, automated assessment of early contrast enhancement, and tumor thickness for response assessment in peritoneal mesothelioma.

Small Extracellular Vesicle-Derived Circular RNA hsa_circ_0007386 as a Biomarker for the Diagnosis of Pleural Mesothelioma.

Pleural mesothelioma (PM) is a highly aggressive tumor that is caused by asbestos exposure and lacks effective therapeutic regimens. Current procedures for PM diagnosis are invasive and can take a long time to reach a definitive result. Small extracellular vesicles (sEVs) have been identified as important communicators between tumor cells and their microenvironment via their cargo including circular RNAs (circRNAs). CircRNAs are thermodynamically stable, highly conserved, and have been found to be dysregulated in cancer. This study aimed to identify potential biomarkers for PM diagnosis by investigating the expression of specific circRNA gene pattern (hsa_circ_0007386) in cells and sEVs using digital polymerase chain reaction (dPCR). For this reason, 5 PM, 14 non-PM, and one normal mesothelial cell line were cultured. The sEV was isolated from the cells using the gold standard ultracentrifuge method. The RNA was extracted from both cells and sEVs, cDNA was synthesized, and dPCR was run. Results showed that hsa_circ_0007386 was significantly overexpressed in PM cell lines and sEVs compared to non-PM and normal mesothelial cell lines (p < 0.0001). The upregulation of hsa_circ_0007386 in PM highlights its potential as a diagnostic biomarker. This study underscores the importance and potential of circRNAs and sEVs as cancer diagnostic tools.

Comparison of FDG-PET/CT and CT for evaluation of tumor response to nivolumab plus ipilimumab combination therapy and prognosis prediction in patients with unresectable malignant pleural mesothelioma.

OBJECTIVES: Results for malignant pleural mesothelioma (MPM) patients following first-line treatment with nivolumab plus ipilimumab obtained with immunotherapy-modified PERCIST (imPERCIST), shown by [18F]fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), and modified RECIST (mRECIST), shown by CT, were compared for response evaluation and prognosis prediction. RESULTS: imPERCIST indicated nine progressive metabolic disease (PMD), eight stable metabolic disease (SMD), four partial metabolic response (PMR), and five complete metabolic response (CMR) cases. mRECIST showed nine with progressive disease (PD), nine stable disease (SD), seven partial response (PR), and one complete response (CR). Although high concordance was noted (κ = 0.827), imPERCIST correctly judged a greater percentage with CMR (15.4%). Following a median 10.0 months, 15 patients showed progression and eight died from MPM. With both, progression-free survival (PFS) and overall survival (OS) were significantly longer in patients without progression (CMR/PMR/SMD, CR/PR/SD, respectively) as compared to PMD/PD patients (imPERCIST p < 0.0001 and p = 0.015, respectively; mRECIST p < 0.0001 and p = 0.015, respectively). METHODS: Twenty-six patients (23 males, 3 females; median 73.5 years) with histologically proven MPM and no curative surgery received nivolumab plus ipilimumab combination therapy. FDG-PET/CT and diagnostic CT scanning at the baseline, and after 2-4 cycles (2 in three, 3 in 17, 4 in six patients) were performed. Therapeutic response findings evaluated using imPERCIST and mRECIST were compared. PFS and OS analyses were done using log-rank and Cox methods. CONCLUSION: For unresectable MPM patient examinations, FDG-PET and CT provide accurate findings for evaluating tumor response and also prognosis prediction following first-line nivolumab plus ipilimumab immunotherapy (approximately three cycles).

A randomised phase II study of extended pleurectomy/decortication preceded or followed by chemotherapy in patients with early-stage pleural mesothelioma: EORTC 1205.

BACKGROUND: The role of surgery in pleural mesothelioma remains controversial. It may be appropriate in highly selected patients as part of a multimodality treatment including chemotherapy. Recent years have seen a shift from extrapleural pleuropneumonectomy toward extended pleurectomy/decortication. The most optimal sequence of surgery and chemotherapy remains unknown. METHODS: EORTC-1205-LCG was a multicentric, noncomparative phase 2 trial, 1:1 randomising between immediate (arm A) and deferred surgery (arm B), followed or preceded by chemotherapy. Eligible patients (Eastern Cooperative Oncology Group 0-1) had treatment-naïve, borderline resectable T1-3 N0-1 M0 mesothelioma of any histology. Primary outcome was rate of success at 20 weeks, a composite end-point including 1) successfully completing both treatments within 20 weeks; 2) being alive with no signs of progressive disease; and 3) no residual grade 3-4 toxicity. Secondary end-points were toxicity, overall survival, progression-free survival and process indicators of surgical quality. FINDINGS: 69 patients were included in this trial. 56 (81%) patients completed three cycles of chemotherapy and 58 (84%) patients underwent surgery. Of the 64 patients in the primary analysis, 21 out of 30 patients in arm A (70.0%; 80% CI 56.8-81.0%) and 17 out of 34 patients (50.0%; 80% CI 37.8-62.2%) in arm B reached the statistical end-point for rate of success. Median progression-free survival and overall survival were 10.8 (95% CI 8.5-17.2) months and 27.1 (95% CI 22.6-64.3) months in arm A, and 8.0 (95% CI 7.2-21.9) months and 33.8 (95% CI 23.8-44.6) months in arm B. Macroscopic complete resection was obtained in 82.8% of patients. 30- and 90-day mortality were both 1.7%. No new safety signals were found, but treatment-related morbidity was high. INTERPRETATION: EORTC 1205 did not succeed in selecting a preferred sequence of pre- or post-operative chemotherapy. Either procedure is feasible with a low mortality, albeit consistent morbidity. A shared informed decision between surgeon and patient remains essential.

Developing a fit-for-purpose composite symptom score as a symptom burden endpoint for clinical trials in patients with malignant pleural mesothelioma.

We developed a composite symptom score (CSS) representing disease-related symptom burden over time in patients with malignant pleural mesothelioma (MPM). Longitudinal data were collected from an open-label Phase IIB study in which 239 patients completed the validated MD Anderson Symptom Inventory for MPM (MDASI-MPM). A blinded, independent review committee of external patient-reported outcomes experts advised on MDASI-MPM symptoms to include in the CSS. Through iterative analyses of potential symptom-item combinations, 5 MPM symptoms (pain, fatigue, shortness of breath, muscle weakness, coughing) were selected. The CSS correlated strongly with the full MDASI-MPM symptom set (0.92-0.94) and the Lung Cancer Symptom Scale-Mesothelioma (0.79-0.87) at each co-administration of the scales. The CSS also had good sensitivity to worsening disease and global quality-of-life ratings. The MDASI-MPM CSS can be used as an outcome in MPM clinical trials, including in responder analyses and at the individual patient level. It is brief enough to administer frequently, including electronically, to better capture symptom trajectories during and after a trial and in clinical practice. As a single score, the CSS addresses multiplicity issues that can arise when several symptoms increase due to worsening disease. Our process can be adapted to produce a CSS for other advanced-cancer trials.

Rethinking continuity in primary care for people with mesothelioma.

BACKGROUND: Mesothelioma is a terminal disease that is linked to asbestos exposure. Continuity is difficult for GPs, and other healthcare professionals (HCPs), to provide within the current NHS primary care system, but is highly valued by people with mesothelioma. AIM: To understand the experiences of continuity in primary care among people with mesothelioma, their close persons, and their HCPs; how they achieve this (or not); and how it affects their healthcare service use. METHOD: Realist case studies of patient journeys through the healthcare system (involving longitudinal interviews with people with mesothelioma, their close persons, and HCPs; and exploration of the organisational context). Data analysis allowed understanding of hidden mechanisms (resources and reasoning), triggered in certain contexts, leading to specific outcomes. RESULTS: Forty-eight interviews (involving 9 patients, 8 close persons, and 12 HCPs) were undertaken (totalling 30.8 hours/1848 minutes). Context-Mechanism-Outcome configurations related to: challenges unique to mesothelioma; capacity of patients/close persons/HCPs to facilitate continuity; multidisciplinary (MDT) approach differs from the family doctor model; and 'the NHS primary care system is broken'. CONCLUSION: Patients perceive their continuity needs to be unmet by the inflexible primary care system, which needs to adapt to a society in which people receive increasingly novel treatments and live longer with complex healthcare needs. A societal perspective shift is required to understand that an MDT now shares responsibility for care, rather than an individual family doctor. Policy documents continue to focus on access, and still do not advocate strongly enough for continuity, despite unequivocal evidence demonstrating its worth.

Air pollution and survival in patients with malignant mesothelioma and asbestos-related lung cancer: a follow-up study of 1591 patients in South Korea.

BACKGROUND: Despite significant advancements in treatments such as surgery, radiotherapy, and chemotherapy, the survival rate for patients with asbestos-related cancers remains low. Numerous studies have provided evidence suggesting that air pollution induces oxidative stress and inflammation, affecting acute respiratory diseases, lung cancer, and overall mortality. However, because of the high case fatality rate, there is limited knowledge regarding the effects of air pollution exposures on survival following a diagnosis of asbestos-related cancers. This study aimed to determine the effect of air pollution on the survival of patients with malignant mesothelioma and asbestos-related lung cancer. METHODS: We followed up with 593 patients with malignant mesothelioma and 998 patients with lung cancer identified as asbestos victims between 2009 and 2022. Data on five air pollutants-sulfur dioxide, carbon monoxide, nitrogen dioxide, fine particulate matter with a diameter < 10 µm, and fine particulate matter with a diameter < 2.5 µm-were obtained from nationwide atmospheric monitoring stations. Cox proportional hazard models were used to estimate the association of cumulative air pollutant exposure with patient mortality, while adjusting for potential confounders. Quantile-based g-computation was used to assess the combined effect of the air pollutant mixture on mortality. RESULTS: The 1-, 3-, and 5-year survival rates for both cancer types decreased with increasing exposure to all air pollutants. The estimated hazard ratios rose significantly with a 1-standard deviation increase in each pollutant exposure level. A quartile increase in the pollutant mixture was associated with a 1.99-fold increase in the risk of malignant mesothelioma-related mortality (95% confidence interval: 1.62, 2.44). For lung cancer, a quartile increase in the pollutant mixture triggered a 1.87-fold increase in the mortality risk (95% confidence interval: 1.53, 2.30). CONCLUSION: These findings support the hypothesis that air pollution exposure after an asbestos-related cancer diagnosis can negatively affect patient survival.

Dendritic cells loaded with allogeneic tumour cell lysate plus best supportive care versus best supportive care alone in patients with pleural mesothelioma as maintenance therapy after chemotherapy (DENIM): a multicentre, open-label, randomised, phase 2/3 study.

BACKGROUND: Dendritic cell immunotherapy has proven to be safe and induces an immune response in humans. We aimed to establish the efficacy of dendritic cells loaded with allogeneic tumour cell lysate (MesoPher, Amphera BV, 's-Hertogenbosch, Netherlands) as maintenance therapy in patients with pleural mesothelioma. METHODS: In this open-label, randomised, phase 2/3 study, patients with histologically confirmed unresectable pleural mesothelioma, aged 18 years or older, with an Eastern Cooperative Oncology Group performance status score of 0-1, and non-progressing disease after four to six cycles of standard chemotherapy (with pemetrexed 500 mg/m2 plus platinum [cisplatin 75 mg/m2 or carboplatin area under the curve of 5]) were recruited from four centres in Belgium, France, and The Netherlands. Participants were randomly assigned (1:1), using block randomisation (block size of 4), stratified by centre and histology (epithelioid vs other), to MesoPher treatment plus best supportive care or best supportive care alone. Patients received up to a maximum of five MesoPher infusions, with treatment administered on days 1, 15, and 29, and weeks 18 and 30. At each timepoint, participants received an injection of 25 × 106 dendritic cells (two-thirds of the dendritic cells were administered intravenously and a third were injected intradermally). Best supportive care was per local institutional standards. The primary endpoint was overall survival, assessed in all participants randomly assigned to treatment (full analysis set) and safety assessed in all randomly assigned participants, and who underwent leukapheresis if they were in the MesoPher group. This study is registered with ClinicalTrials.gov, NCT03610360, and is closed for accrual. FINDINGS: Between June 21, 2018, and June 10, 2021, 176 patients were screened and randomly assigned to the MesoPher group (n=88) or best supportive care alone group (n=88). One participant in the MesoPher group did not undergo leukapheresis. Mean age was 68 years (SD 8), 149 (85%) of 176 were male, 27 (15%) were female, 173 (98%) were White, two were Asian (1%), and one (1%) was other race. As of data cutoff (June 24, 2023), after a median follow up of 15·1 months (IQR 9·5-22·4), median overall survival was 16·8 months (95% CI 12·4-20·3; 61 [69%] of 88 died) in the MesoPher group and 18·3 months (14·3-21·9; 59 [67%] of 88 died) in the best supportive care group (hazard ratio 1·10 [95% CI 0·77-1·57]; log-rank p=0·62). The most common grade 3-4 treatment-emergent adverse events were chest pain (three [3%] of 87 in the MesoPher group vs two [2%] of 88 in the best supportive care group), dyspnoea (none vs two [2%]), anaemia (two [2%] vs none), nausea (none vs two [2%]), and pneumonia (none vs two [2%]). No deaths due to treatment-emergent adverse events were recorded. Treatment-related adverse events consisted of infusion-related reactions (fever, chills, and fatigue), which occurred in 64 (74%) of 87 patients in the MesoPher group, and injection-site reactions (itch, erythema, and induration), which occurred in 73 (84%) patients, and all were grade 1-2 in severity. No deaths were determined to be treatment related. INTERPRETATION: MesoPher did not show improvement in overall survival in patients with pleural mesothelioma. Immune checkpoint therapy is now standard of care in pleural mesothelioma. Further randomised studies are needed of combinations of MesoPher and immune checkpoint therapy, which might increase efficacy without adding major toxicities. FUNDING: Amphera BV and EU HORIZON.

Comparative efficacy of immune checkpoint inhibitors versus chemotherapy alone in diffuse pleural mesothelioma.

BACKGROUND: This study aimed to investigate the effects of immune checkpoint inhibitors (ICIs) versus chemotherapy on the prognosis of real-world diffuse pleural mesothelioma patients in China. METHODS: Clinical data of 90 patients with diffuse pleural mesothelioma from 2019 to 2022 were collected from Harbin Medical University Cancer Hospital. Patients were divided into two groups: the ICIs-treated group (n = 46) and the chemotherapy-only group (n = 44). The efficacy and safety of immunotherapy relative to chemotherapy at different treatment stages were explored. RESULTS: The median progression-free survival (PFS) was 10.0 and 7.0 months, and the median overall survival (OS) was 24.7 and 15.8 months in the ICIs-treated group and the chemotherapy group, respectively. The ICIs-treated group showed an 11% increase in objective response rate (ORR) (52.2% vs. 41.0%) and an 8.0% increase in disease control rate (DCR) (78.3% vs. 70.0%) compared to the chemotherapy group. The Kaplan-Meier curves demonstrated significant PFS (HR: 0.61; 95% CI: 0.38-0.98; p = 0.038) and OS (HR: 0.47; 95% CI: 0.26-0.86; p = 0.011) benefits of receiving immunotherapy over chemotherapy alone. Subgroup analysis according to treatment timing showed the same trend. CONCLUSION: In patients with nonsurgical diffuse pleural mesothelioma, immunotherapy achieved better survival benefits compared to chemotherapy in both first- and second-/third-line treatments. The early addition of immunotherapy improved survival in patients with nonsurgical diffuse pleural mesothelioma.

Female Adnexal Tumor of Probable Wolffian Origin (Wolffian Tumor): A Potential Mimic of Peritoneal Mesothelioma.

Wolffian tumor and its nosologic relative, the recently defined STK11 adnexal tumor are rare neoplasms thought to arise from mesonephric remnants. These tumors typically arise in the broad ligament, fallopian tube, and ovarian hilum and although most are associated with a good prognosis, up to 50% of STK11 adnexal tumors demonstrate aggressive clinical behavior. The chief differential diagnoses include endometrioid adenocarcinoma and sex cord stromal tumors. However, the morphologic and immunohistochemical features of these tumors exhibit considerable overlap with peritoneal mesothelioma. To fully characterize their immunophenotypic signature, we examined a total of 21 cases (18 Wolffian and 3 STK11 adnexal tumors) with standard markers used in the diagnosis of mesothelioma. Morphologic and immunohistochemical (IHC) features were reviewed and additional IHC performed for cases with available material. Patient age ranged from 25 to 73 (mean: 51) years. Sites included adnexa/broad ligament (6, 28%), paratubal (5, 24%), ovary/paraovarian (5, 24%), tubal (intraluminal) (2, 9.5%), pelvis (2, 9.5%), and liver (1, 5%). The mean tumor size was 9.3 cm (range: 0.2 to 22 cm). The histomorphology in most cases (14/21, 66%) consisted of tubular to solid sheets of neoplastic cells lined by columnar to cuboidal cells containing uniform round to oval nuclei. Compressed tubules with slit-like lumens and sieve-like pattern were also seen in at least 7 (33%) cases. Three cases demonstrated interanastomosing cords and trabeculae of epithelioid cells with cribriform and microacinar patterns growing within prominent myxoid stroma as described in STK11 adnexal tumors. In the cases with available IHC for 3 mesothelial markers (calretinin, WT1, D2-40), 55.5% (5 of 9) showed reactivity with all 3 markers. In cases with at least 2 available mesothelial markers, 69% (11/16) were positive for 2 markers (mostly calretinin and WT1). Claudin-4, MOC31, and BER-EP4 were negative in most cases tested (78% [7/9], 71.4% [5/7], and 100% [6/6], respectively). Given the resemblance to mesothelioma, there was initial strong consideration and/or actual misdiagnosis of mesothelioma in 3 cases (14%). In summary, the morphologic and immunohistochemical features of Wolffian tumor and its recently defined relative, STK11 adnexal tumor, can lead to misdiagnosis of mesothelioma, particularly when encountered in the disseminated or metastatic setting. Wolffian tumor and STK11 adnexal tumor should be considered in the differential diagnosis of all pelvic and peritoneal mesotheliomas.

Time-course RNAseq data of murine AB1 mesothelioma and Renca renal cancer following immune checkpoint therapy.

Time-critical transcriptional events in the immune microenvironment are important for response to immune checkpoint blockade (ICB), yet these events are difficult to characterise and remain incompletely understood. Here, we present whole tumor RNA sequencing data in the context of treatment with ICB in murine models of AB1 mesothelioma and Renca renal cell cancer. We sequenced 144 bulk RNAseq samples from these two cancer types across 4 time points prior and after treatment with ICB. We also performed single-cell sequencing on 12 samples of AB1 and Renca tumors an hour before ICB administration. Our samples were equally distributed between responders and non-responders to treatment. Additionally, we sequenced AB1-HA mesothelioma tumors treated with two sample dissociation protocols to assess the impact of these protocols on the quality transcriptional information in our samples. These datasets provide time-course information to transcriptionally characterize the ICB response and provide detailed information at the single-cell level of the early tumor microenvironment prior to ICB therapy.