Search Results (390)

Background and Clinical Significance: Lymph node metastases from carcinoma of unknown primary origin (CUP) are a rare and diagnostically challenging entity, particularly when arising from thoracic malignancies with atypical clinical presentations. This study aims to illustrate the essential nature of multidisciplinary integration, with a particular emphasis on the role of the pathologist in identifying occult thoracic tumors. Case Presentation: We report three cases of patients presenting with cervical or systemic lymphadenopathy as the initial clinical manifestation. Comprehensive diagnostic workups included advanced imaging (CT, MRI, and PET), comprehensive histopathological analysis, and next-generation sequencing of circulating tumor DNA. Case one and case two were diagnosed as occult primary non-mucinous lung adenocarcinomas, based on the integration of morphological features and immunohistochemical co-expression of TTF-1 and Napsin A, despite the absence of identifiable lung lesions. One case harbored an ALK rearrangement, guiding effective targeted therapy with alectinib. Case three involved metastatic pleural epithelioid mesothelioma, which presented with systemic lymphadenopathy and was initially misclassified as metastatic adenocarcinoma. Diagnosis was confirmed by the loss of BAP1 expression by immunohistochemistry and the detection of a BAP1 S160fs*1 mutation, emphasizing the role of molecular pathology. Conclusions: Lymphadenopathy as the first manifestation of thoracic malignancy is a rare but clinically significant occurrence. In such atypical presentations, pathologists play a pivotal role in diagnosis, often leading the process when clinical or radiological clues are minimal or absent. Accurate histopathological assessment is essential to establish a correct diagnosis and guide appropriate therapy. A multidisciplinary approach remains the cornerstone of diagnostic precision in CUP cases. Full article

Background: Pleural mesothelioma (PM) is characterised by often rapid therapeutic failure and chemotherapy resistance. While terminal resistance is well studied, the initial transition into a drug-tolerant phenotype remains poorly understood. Methods: We established patient-derived organoids (PDOs) from malignant pleural effusions to model this transition. Cisplatin-tolerant lines were generated via repeated incremental exposure to cisplatin and compared to time-matched treatment-naive controls using RNA sequencing and Seahorse XFe96 metabolic flux analysis. Results: Integrated profiling suggested that the route to tolerance may be influenced by the underlying mutational profile. In this cohort, all BAP1-retained models (including those with KRAS mutations or MTAP loss) adopted an elevated basal metabolic hybrid phenotype, significantly upregulating baseline oxidative phosphorylation and glycolysis to fuel survival mechanisms. Conversely, BAP1-deficient models entered a hypometabolic state of dormancy, characterised by baseline bioenergetic suppression and reduced Ki-67 proliferation. Transcriptomic analysis identified a vesicular transport signature (SYNGR3, VPS52, PROM2) in plastic models, suggesting altered membrane trafficking as a potential survival strategy. Conclusions: Our findings demonstrate that mesothelioma therapeutic escape is not a uniform process. Identifying these patient-specific metabolic and transcriptomic trajectories via 3D PDOs provides a hypothesis-generating framework to explore potential avenues for future personalised therapy. Full article

Background and Objectives: The presence of comorbidities in both the pre- and post-diagnostic periods is a critical consideration in the diagnosis and management of patients with cancer. This study aimed to investigate the prevalence and burden of pulmonary and extrapulmonary comorbidities in patients diagnosed with lung cancer (LC) and malignant pleural mesothelioma (MPM). Materials and Methods: The data were obtained from official patient records of the Turkish Ministry of Health. Patients diagnosed with either lung cancer (LC) or malignant pleural mesothelioma (MPM) between 2015 and 2018 were included in the study. Comorbidities were classified as pulmonary or extrapulmonary. Results: A total of 74,835 patients with LC and 1678 patients with MPM were included. The burden of comorbid conditions increased significantly in the post-diagnostic period in both males and females across both cancer types. When the two cancer groups were compared with respect to diagnostic periods, comorbidities such as hypertension (HT), phlebitis/venous thrombosis/thrombophlebitis, pulmonary embolism, pneumothorax, and pleural effusion were significantly more prevalent in the MPM group (p < 0.05). Compared with the pre-diagnostic period, the comorbidity risk in LC was highest for pulmonary embolism, ARF, and pneumonia in the post-diagnostic period, whereas renal failure was the most frequent comorbidity in the MPM group (p < 0.001 and p = 0.024). When comparing changes in comorbidity burden between sexes in the lung cancer group, male patients had higher frequencies of pulmonary embolism, pneumonia, pneumothorax, and coronary artery disease than females. In contrast, in the female lung cancer group, the prevalence of chronic renal failure was higher than in males (OR = 2.14 vs. 2.00), whereas acute renal failure was more prominent in the male patient group (OR = 2.64 vs. 1.94). In gender-based comparison of comorbid conditions among patients with MPM, the risk of renal failure was higher in females than in males (CRF and ARF respectively: OR = 2.63 vs. 2.16 and OR = 6.80 vs. 5.44). Additionally, increased rates of COPD were observed in male patients within this group (OR = 1.93 vs. 1.81). Conclusions: Patients with LC and MPM are burdened not only by their primary malignancies but also by a wide spectrum of comorbidities, particularly in the post-diagnostic period. Comprehensive knowledge of comorbid conditions is essential for clinicians to guide clinical decision-making, anticipate disease progression, and optimize treatment strategies, thereby informing national healthcare policies. Future studies incorporating matched control groups or longitudinal designs with standardized surveillance protocols may help conduct better research. Full article

Accurate diagnosis of PM and precise histologic subtyping are critical for optimal therapeutic decision-making, as treatment strategies—including chemotherapy, immunotherapy, or multimodality approaches—are largely subtype-dependent. Because of the several-decade latency between fiber inhalation and symptom onset, many cases are diagnosed at an advanced stage, when patients are already in poor clinical condition. As observed across multiple solid malignancies, earlier-stage diagnosis is associated with improved prognosis and expanded therapeutic options. However, the rarity of PM, the absence of validated screening strategies, and its nonspecific clinical and radiologic presentation—often mimicking both benign and metastatic pleural conditions, frequently result in diagnostic delay. Furthermore, the lack of pathognomonic histopathologic markers further complicates timely and definitive diagnosis. This review aims to delineate the epidemiologic, clinical, radiologic, and pathologic barriers that hinder accurate and early detection of PM. Current clinical evidence points to an urgent need to develop novel, validated biomarkers in PM, which will require a multidisciplinary approach. Full article

Pleural Mesothelioma (PM) is a rare, incurable malignancy of the pleura. Lung-sparing surgery, considered investigational, aims to prolong survival and improve quality of life (QOL). Beyond the standard quantitative measures used to determine successful surgical outcomes, an understanding of an individual’s perception of the impact surgery has had on their symptom burden and QOL has not been reported in the literature. The primary aim of this study was to explore the lived experience of dyspnea and QOL before and after lung-sparing surgery. The philosophical approach to this study was grounded in hermeneutical phenomenology. Participants underwent in-depth semi-structured interviews before and 3–4 months post-surgery, analyzed through Interpretive Phenomenological analysis. The analysis identified Group Experiential Themes (GETs) before and after surgery: Psychological (mind supports body), Physiological (body fighting, enduring, and adapting), Social (others sharing and supporting), and Existential (facing an uncertain future). The emotional impact of PM is multidimensional, involving time, internal psychological struggles, and coping with the diagnosis. The physical impact disrupts normal routines and interactions, while social interactions influence the perception of the illness experience. Facing PM disrupts normal bodily routines and interactions with the world. This study provides qualitative evidence that perceptions of dyspnea and QOL significantly impact the patient experience before and after surgery. The enriched understanding of living with mesothelioma and enduring lung-sparing surgery comes from the patients’ voices, highlighting the continuum of dyspnea and QOL influenced by various factors. Healthcare teams must consider patients’ physical, emotional, social, and existential experiences beyond measurable outcomes. Full article

Background/Objective: The identification of novel non-invasive diagnostic and prognostic biomarkers is urgently needed in pleural mesothelioma (PM). While soluble mesothelin-related peptides (SMRP) are the most established circulating biomarker, their prognostic value is limited. A wide range of microRNAs (miRs) play diverse roles in regulating gene expression in PM. MiR-21 has been shown to be upregulated in mesothelioma tissue; nevertheless, the diagnostic and prognostic utility of miR-21 in the circulation and its association with survival in PM have not been extensively investigated to date. The objective of the current study was to evaluate miR-21 as a potential blood-based diagnostic and prognostic biomarker in PM. Methods: Plasma samples from PM patients (n = 94) were collected at the time of diagnosis, prior to treatment. Sex- and age-matched healthy individuals (n = 30) served as controls. MiR-21 levels were measured using quantitative RT-PCR and normalized to miR-16, and potential correlations with clinicopathological data were analyzed. Serum SMRP levels were measured in matched patients (n = 84), and a direct comparative analysis of miR-21 and SMRP was conducted. In situ hybridization (ISH) was used to confirm the presence of miR-21 in tumor cells. Results: Plasma miR-21 levels were significantly elevated in PM patients compared to healthy controls (p < 0.001), demonstrating good diagnostic performance (AUC 0.81). The localization of miR-21 in PM cells was confirmed by ISH. High miR-21 levels were associated with significantly shorter median overall survival (12.4 vs. 24.3 months, p < 0.001). Elevated SMRP levels were also associated with reduced survival (12.4 vs. 19.5 months, p = 0.032); however, SMRP did not retain independent prognostic significance in multivariable analysis. In contrast, high-circulating miR-21 was confirmed as an independent predictor for poor survival (HR 3.12, p < 0.001). Conclusions: Our findings highlight that circulating miR-21 is a potential non-invasive biomarker with both diagnostic and independent prognostic value in pleural mesothelioma and outperforms SMRP in multivariable survival analysis. Further research is warranted to validate its role in the biology of this disease and to assess its correlation with outcome and treatment responses. Full article

Background/Objectives: Malignant mesothelioma has a poor prognosis and limited therapeutic options. C-ERC/mesothelin is highly expressed in mesotheliomas and is a potential target for radioimmunotherapy (RIT). This study evaluated the radiolabeled anti-C-ERC/mesothelin antibody mAb 22A31 as a therapeutic agent. Methods: C-ERC/mesothelin expression in mesothelioma cell lines was assessed by Western blotting, and the specific binding of ¹²⁵I-labeled mAb 22A31 was examined. Biodistribution of ¹¹¹In-labeled mAb 22A31 was evaluated in a mesothelioma cell line, MSTO-211H tumor-bearing mice. The therapeutic efficacy of ⁹⁰Y-labeled mAb 22A31 was evaluated in subcutaneous and pleural dissemination models. Results: mAb 22A31 showed specific binding considering the level of C-ERC/mesothelin expression in each mesothelioma cell line. ¹¹¹In-mAb 22A31 accumulated in tumors with minimal uptake in normal tissues. ⁹⁰Y-mAb 22A31 significantly delayed the growth of subcutaneous tumors and improved survival in a pleural dissemination model. Conclusions: Radiolabeled mAb 22A31 specifically targeted C-ERC/mesothelin and demonstrated therapeutic efficacy in a mesothelioma xerograph model. Therefore, ⁹⁰Y-mAb 22A31 is a promising RIT agent and supports the further development of C-ERC/mesothelin-targeted therapy for mesothelioma. Full article

Malignant pleural mesothelioma (MPM) is a rare and aggressive tumor associated with asbestos exposure, which represents a current problem. MPM is characterized by a poor prognosis and an unsatisfactory therapeutic approach. Therefore, improving MPM prognosis is the real challenge for research today. Regarding preclinical data, Transforming Growth Factor-β (TGF-β) plays a crucial role in cancer, and its alteration has been associated with tumor progression and invasiveness, in particular through the Epithelial to Mesenchymal Transition (EMT) event. We investigated the role of TGF-β inhibition in proliferation, cell cycle, migration, and invasiveness in human MPM cells. Data obtained clearly highlighted how TGF-β inhibition, through the silencing or treatment of MPM cells with antibody anti-TGF-β (Fresolimumab), significantly reduces cell proliferation (MTT, PCNA) and prevents metastasis, reducing EMT and decreasing the invasiveness and migration of MPM cells. Finally, we also evaluated TGF-β inhibitory effects in 3D MPM cellular models (spheroids), highlighting a significant slowdown in the growth rate of spheroids treated with anti-TGF-β antibody or Fresolimumab, confirming the results previously obtained. Taken as a whole, targeting TGF-β will represent a starting point for future improvements in MPM management. This is particularly important as we foresee a growing increase in MPM in the coming years. Full article

Pleural mesothelioma (PM) is a rare malignancy with opportunities for improvement in current treatment paradigms despite recent advances in systemic therapy. While histology remains the most clinically relevant prognostic indicator, the expanding use of immunotherapy and ongoing clinical trials involving targeted therapies have increased interest in the development of predictive and prognostic biomarkers in this disease. This review summarizes the current biologic and therapeutic landscape of PM and the biomarkers that influence prognosis and treatment response. Biomarkers such as programmed death ligand 1 (PD-L1) expression and tumor mutational burden (TMB) demonstrate inconsistent predictive value in PM and are not currently used in clinical decision pathways in the real-world setting. This review highlights the developing role of dynamic biomarkers such as circulating tumor DNA (ctDNA) for molecular response assessment and minimal residual disease (MRD) detection. This review also examines important genomic and transcriptomic alterations in PM, such as MTAP, BAP1, CDKN2A, and NF2/YAP/TEAD. These alterations provide potential targets for ongoing early-phase clinical trials. Future advances in PM will depend on the development and integration of comprehensive biomarker models that combine clinicopathologic, immune, and molecular features of this complex and heterogenous disease. Full article

Immunotherapy has significantly reshaped the management of malignant pleural mesothelioma (MPM), offering new therapeutic opportunities after decades in which platinum–pemetrexed chemotherapy represented the only systemic option. However, clinical benefit remains markedly heterogeneous, with outcomes strongly influenced by histologic subtype, patient characteristics, and real-world treatment conditions. Evidence from monotherapy trials has been inconsistent, whereas combination approaches—particularly nivolumab plus ipilimumab—have demonstrated improved survival compared with chemotherapy, mainly in non-epithelioid tumors. Nevertheless, real-world data consistently show lower efficacy and higher toxicity than registrational studies, especially among elderly and unselected populations. Recent translational work has highlighted the relevance of the tumor microenvironment and recurrent genomic alterations such as BAP1, NF2, and CDKN2A in shaping immune activity and potentially modulating response to immune checkpoint inhibitors. Transcriptomic signatures and circulating biomarkers—including soluble mesothelin-related peptide—have shown prognostic associations but no validated predictive value. Overall, current evidence suggests that sensitivity to immunotherapy in MPM arises from a complex interplay of genomic, immunologic, and clinical factors, and that no biomarker is yet suitable for guiding treatment decisions. Prospective studies integrating molecular and immune profiling will be essential to refine patient selection and advance toward a more rationally personalized use of immunotherapy Full article

SATB2 (special AT-rich binding protein 2) functions as a chromatin-associated epigenetic regulator that modulates gene expression, in part by serving as a transcriptional cofactor. This study assessed whether SATB2 overexpression is sufficient to promote in vitro transformation of human mesothelial cells and whether SATB2 suppression in mesothelioma cancer stem cell (CSC)–enriched populations is associated with altered chemoresistance. SATB2 expression was high in human malignant pleural mesothelioma (MPM) cell lines but absent in Met5A mesothelial cells. Ectopic SATB2 expression in Met5A cells was associated with acquisition of malignant and stem cell–like phenotypes, including increased expression of stem cell markers and pluripotency-associated factors, as well as anchorage-independent growth in soft agar and spheroid formation in suspension culture. In contrast, Met5A cells transduced with an empty vector did not form colonies or mesospheres. SATB2 overexpression in Met5A cells was also associated with increased motility, migration, and invasion, accompanied by induction of epithelial–mesenchymal transition (EMT)–related transcription factors relative to empty vector controls. Conversely, shRNA-mediated SATB2 knockdown in an MPM cell line attenuated proliferation, EMT-associated features, and CSC-like characteristics. Chromatin immunoprecipitation assays identified SATB2 occupancy at promoter regions of Bcl2, XIAP, KLF4, c-Myc, NANOG, and SOX2, consistent with a role in transcriptional regulation of genes linked to transformation, pluripotency, cell survival, proliferation, and EMT. In CSC-enriched cells, SATB2 inhibition was associated with increased sensitivity to cisplatin and pemetrexed, concomitant with reduced OCT4 and SOX2 expression. Collectively, these findings support SATB2 as a candidate therapeutic target in MPM and suggest that SATB2 suppression may enhance chemotherapy response when combined with standard agents. Full article

Background: Malignant pleural mesothelioma (MPM) is an aggressive neoplasm, the major cause of which is asbestos exposure. Adjuvant radiotherapy after pleurectomy/decortication (P/D) aims at reducing locoregional recurrence but is limited by the risk of radiation pneumonitis (RP). In this study, we attempted to evaluate the predictive value of conventional and functional dosimetric parameters in assessing RP risk. Methods: This retrospective study analyzed 68 patients with non-metastatic MPM treated with adjuvant radiotherapy after P/D. Dosimetric parameters, including V20, V5, and mean lung dose (MLD), were calculated for both total lung volume and functional lung volume (FLV), with emphysematous regions excluded based on CT imaging thresholds. Statistical analyses assessed correlations between these parameters and acute RP incidence. Results: Acute RP developed in 42% of patients, and 28% had moderate-to-severe (Grade 2–3) events. V20 and FCL_V20 were significantly associated with the risk of RP (p = 0.017 and p = 0.028, respectively). Predictive accuracy for conventional V20 (AUC = 0.668) and Functional Contralateral Lung V20 (FCL_V20) (AUC = 0.655) showed moderate efficacy, without further significant improvement in using functional parameters. A V20 threshold > 1.8% predicted severe RP with high specificity (89.8%). Conclusions: While functional lung delineation provides an alternative in dosimetry, conventional V20 is a robust predictor of RP. Optimization of dosimetric constraints, in an effort to reduce pulmonary toxicity in MPM patients, should be further combined with advanced radiotherapy techniques and biomarkers. Full article

Background/Objectives: Pleural mesothelioma (PM) frequently recurs despite multimodal therapy. Here, we aimed to retrospectively evaluate the safety and potential clinical benefit of radiofrequency ablation (RFA) for recurrent PM. Methods: Fourteen consecutive patients underwent CT-guided RFA between July 2019 and June 2025. The cohort comprised 13 men and 1 woman, with a median age of 69 (range, 54–77) years. All patients had previously received systemic therapy, and 12 had undergone surgery. Seven patients (50%) presented with multiple lesions, and 25 tumors (median diameter 1.8 cm; range, 0.5–7.0 cm) were treated in 23 sessions. Outcomes assessed were local tumor control, complications, and survival. Local progression and overall survival were estimated using Kaplan–Meier analysis. Adverse events were classified according to the Society of Interventional Radiology guidelines. Results: Technical success was achieved in all sessions. Two tumors showed local recurrence, corresponding to 1- and 2-year local progression rates of 10.6%. Seven patients showed distant metastases, most of whom subsequently received systemic therapy. Three patients died, two from disease progression and one from treatment-related gastrointestinal perforation during therapy for an unrelated cancer. The overall survival rates were 100%, 100%, and 60% at 1, 3, and 5 years, respectively. Major and minor complications occurred in one case each (4.3%): a refractory skin ulcer and retroperitoneal hematoma, respectively. Conclusions: RFA was technically feasible and generally well tolerated and helped achieve encouraging local control and survival in patients with recurrent PM, warranting further evaluation of RFA as a complementary approach in multimodal treatment strategies. Full article

Malignant pleural mesothelioma (MPM) is a very aggressive tumor. The prognostic value of PD-L1 and BAP1 expression has been investigated in many studies. A retrospective study was conducted that analyzed PD-L1 and BAP1 expression as prognostic biomarkers in patients with MPM. The study included 53 patients with MPM. PD-L1 expression ≥ 1% was found in 39.6%, and BAP1 loss was found in 81.1% of patients. The median overall survival (mOS) was 11 months. Subtype of MPM (p = 0.045), early tumor stage (p = 0.049), therapy (p = 0.002), and good PS (0–1) (p = 0.012) were associated with better survival. Expression of PD-L1 and BAP1 did not show statistical significance regarding OS, but OS was numerically shorter in patients with PD-L1 ≥ 10% (5 vs. 12 months) and longer in patients with BAP1 loss (12 vs. 4 months). In patients with PD-L1 ≥ 1% and BAP1 loss, the median progression-free survival (mPFS) was numerically longer (10 vs. 7 months) but in patients with PD-L1 ≥ 1% and BAP1 positivity, PFS was statistically significantly shorter (1 vs. 7 months, p = 0.048). Our results did not show that PD-L1 and BAP1 are prognostic biomarkers for MPM, but positive PD-L1 expression and BAP1 loss were associated with worse survival in patients with MPM. Full article

Reactive oxygen species (ROS)-induced aberrant oncogenic signalling has been proposed to mediate the progression and development of pleural mesothelioma (PM). In this study, we demonstrate how ROS promote oncogenic signalling, especially in the context of cell migration and immune evasion via YB-1 phosphorylation in mesothelial and PM cell models. Xanthine (X)- and xanthine oxidase (XO)-generated ROS exposure led to increased migration and a more elongated cell shape in mesothelial and PM cells in live-cell videomicroscopy analyses. These effects were associated with the enhanced phosphorylation of ERK, AKT, and YB-1 and the elevated gene expression of PD-L1 and PD-L2, which were analysed with immunoblotting and quantitative real-time RT-PCR, respectively. The pharmacological inhibition of AKT (ipatasertib), MEK (trametinib), and RSK (BI-D1870) resulted in the reversal of ROS-induced effects, with the strongest effects observed upon the inhibition of YB-1 phosphorylation by BI-D1870. The results suggest that ROS exposure has a strong impact on cell migration and immune evasion not only in PM cells but also in mesothelial cells, from which PM arises. Interfering with ROS-responsive kinase pathways, particularly YB-1 phosphorylation, could counteract pro-migratory and immune-evasive effects in PM. Full article