Project description:Malignant pleural mesothelioma (MPM) is a rare disease of the pleura and is largely related to asbestos exposure. Despite recent advancements in technologies and a greater understanding of the disease, the prognosis of MPM remains poor; the median overall survival rate is about 6 to 9 months in untreated patients. The main therapeutic strategies for MPM are surgery, chemotherapy, and radiation therapy (RT). The two main surgical approaches for MPM are extrapleural pneumonectomy (EPP), in which the lung is removed en bloc, and pleurectomy/decortication, in which the lung stays in situ. Chemotherapy usually consists of a platinum-based chemotherapy, such as cisplatin, often combined with a folate antimetabolite, such as pemetrexed. More recently, immunotherapy has emerged as a possible therapeutic strategy for MPM. Evidence suggests that single-modality treatments are not an effective therapeutic approach for MPM. Therefore, researchers have started to explore different multimodality treatment approaches, in which often combinations of surgery, chemotherapy, immunotherapy, and RT are investigated. There is still no definitive answer to the question of which multimodality treatment combinations are most effective in improving the poor prognosis of MPM. Research into the effects of trimodality treatment approaches have found that radical approaches such as EPP and hemithoracic RT post-EPP are less effective than was previously assumed. In general, there are still a great number of unanswered questions and unknown factors regarding the ideal treatment approach for MPM. Hopefully, more research into multimodality therapy will provide insight into which combination of treatment modalities is most effective.
Project description:Malignant pleural mesothelioma is an aggressive tumor of the pleura with an overall poor prognosis. Even with surgical resection, for which only a subset of patients are eligible, long term disease free survival is rare. Standard first-line systemic treatment consists of a platinum analog, an anti-metabolite, and sometimes anti-angiogenic therapy, but there is currently no well-established standard therapy for refractory or relapsed disease. This review focuses on efforts to develop improved systemic therapy for the treatment of malignant pleural mesothelioma (MPM) including cytotoxic systemic therapy, a variety of tyrosine kinase inhibitors and their downstream effector pathways, pharmacologic targeting of the epigenome, novel approaches to target proteins expressed on mesothelioma cells (such as mesothelin), arginine depletion therapy, and the emerging role of immunotherapy. Overall, these studies demonstrate the challenges of improving systemic therapy for MPM and highlight the need to develop therapeutic strategies to control this disease.
Project description:PurposeWe conducted a two-center phase II study to determine the safety of hemithoracic intensity-modulated pleural radiation therapy (IMPRINT) after chemotherapy and pleurectomy-decortication (P/D) as part of a multimodality lung-sparing treatment.Patients and methodsPatients received up to four cycles of pemetrexed plus platinum. If feasible, P/D was performed. Hemithoracic IMPRINT was administered to a planned dose of 50.4 Gy in 28 fractions. The primary end point was the incidence of grade 3 or greater radiation pneumonitis (RP).ResultsA total of 45 patients were enrolled; 18 were not evaluable (because of disease progression before radiation therapy [RT], n = 9; refusal of surgery or RT, n = 5; extrapleural pneumonectomy at time of surgery, n = 2; or chemotherapy complications, n = 2). A total of 26 patients received pemetrexed plus cisplatin, 18 received pemetrexed plus carboplatin, and four received a combination. Thirteen patients (28.9%) had a partial response, 15 patients (33.3%) experienced disease progression, one patient died during chemotherapy, and all others had stable disease. Eight patients underwent P/D or an extended P/D, and 13 underwent a partial P/D. A total of 27 patients started IMPRINT (median dose, 46.8 Gy; range, 28.8 to 50.4 Gy) and were evaluable for the primary end point (median follow-up, 21.6 months). Six patients experienced grade 2 RP, and two patients experienced grade 3 RP; all recovered after corticosteroid initiation. No grade 4 or 5 radiation-related toxicities were observed. The median progression-free survival and overall survival (OS) were 12.4 and 23.7 months, respectively; the 2-year OS was 59% in patients with resectable tumors and was 25% in patients with unresectable tumors.ConclusionsHemithoracic IMPRINT for malignant pleural mesothelioma (MPM) is safe and has an acceptable rate of RP. Its incorporation with chemotherapy and P/D forms a new lung-sparing treatment paradigm for patients with locally advanced MPM.
Project description:Malignant pleural mesothelioma (MPM) is a particularly aggressive thoracic malignancy with limited survival following combination chemotherapy. As a result, there has been increased interested in immunotherapy for mesothelioma, both in the first-line and salvage settings. Early investigations of interleukin-2 (IL-2) and interferon alfa-2a/b have been limited by modest response rates and toxicity, whereas cytokine gene therapy is currently being investigated and shows early promise. The most prominent class of immunotherapies to be trialed with mesothelioma in the past half-decade has been immune checkpoint inhibitors (CPI). Early results are encouraging, particularly for agents targeting the PD-1/PD-L1 pathways. With the increasing recognition of the immune potential of mesothelioma, interest in the immunomodulatory properties of radiation therapy has emerged. The combination of immunotherapy and radiation therapy may allow for complimentary immunologic effects that can enhance antitumor response. This article reviews the existing literature on the efficacy of immunotherapy for MPM, describes the rationale for combining immunotherapy with radiation therapy, and discusses early literature on this treatment combination.
Project description:Malignant pleural mesothelioma (MPM) is a highly lethal, poorly understood neoplasm that is typically associated with asbestos exposure. We performed transcriptional profiling using high-density oligonucleotide microarrays containing approximately 22,000 genes to elucidate potential molecular and pathobiological pathways in MPM using discarded human MPM tumor specimens (n=40), normal lung specimens (n=4), normal pleura specimens (n=5), and MPM and SV40-immortalized mesothelial cell lines (n=5). In global expression analysis using unsupervised clustering techniques, we found two potential subclasses of mesothelioma which correlate loosely with tumor histology. We also identified sets of genes with expression levels that distinguish between multiple tumor subclasses, normal and tumor tissues, and tumors with different morphologies. Microarray gene expression data were confirmed using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and protein analysis for three novel candidate oncogenes (NME2, CRI1, and PDGFC) and one candidate tumor suppressor (GSN). Finally, we used bioinformatics tools (i.e. software) to create and explore complex physiological pathways that may be relevant in mesothelioma tumorigenesis, pathobiology, or both. Tissues and cell lines profiled using microarrays. Discarded MPM surgical specimens (n=40), normal pleura specimens (n=5), and normal lung specimens (n=4) were freshly collected (and snap frozen) from patients who underwent surgery at Boston's Brigham and Women's Hospital (BWH) between October 1998 and August 2000. All of these patients underwent extrapleural pneumonectomy with heated intra-pleural cisplatin chemotherapy delivered after the specimens were removed. All normal specimens were obtained from patients who were never diagnosed with MPM. Two human MPM cell lines (MS589 and MS428) were kindly provided by Jonathan A. Fletcher, M.D., Department of Pathology, BWH. The JMN1B MPM cell line19,20 has been described previously. The SV40-immortalized, non-tumorigenic mesothelial cell line (Met-5A)21 and the MPM cell line MSTO-211H22 were purchased from the American Type Culture Collection. Normal tissues were obtained from additional consented patients undergoing treatment for diseases other than MPM. All MPM samples used in these studies contained relatively pure tumor (greater than 50% tumor cells per high power field examined in a section adjacent to the tissue used). The microscopic slides from the patients' resection specimens were reviewed by one of the authors (J.G.), and the diagnosis and histologic subclassification of MPM confirmed in all cases. Linked clinical and pathological data were obtained for all patients who contributed tumor specimens. Specimens and data were rendered anonymous to protect patient confidentiality. Studies utilizing human tissues were approved by and conducted in accordance with the policies of the Institutional Review Board at BWH.
Project description:PurposeWe previously reported our technique for delivering intensity modulated radiation therapy (IMRT) to the entire pleura while attempting to spare the lung in patients with malignant pleural mesothelioma (MPM). Herein, we report a detailed pattern-of-failure analysis in patients with MPM who were unresectable or underwent pleurectomy/decortication (P/D), uniformly treated with hemithoracic pleural IMRT.Methods and materialsSixty-seven patients with MPM were treated with definitive or adjuvant hemithoracic pleural IMRT between November 2004 and May 2013. Pretreatment imaging, treatment plans, and posttreatment imaging were retrospectively reviewed to determine failure location(s). Failures were categorized as in-field (within the 90% isodose line), marginal (<90% and ≥50% isodose lines), out-of-field (outside the 50% isodose line), or distant.ResultsThe median follow-up was 24 months from diagnosis and the median time to in-field local failure from the end of RT was 10 months. Forty-three in-field local failures (64%) were found with a 1- and 2-year actuarial failure rate of 56% and 74%, respectively. For patients who underwent P/D versus those who received a partial pleurectomy or were deemed unresectable, the median time to in-field local failure was 14 months versus 6 months, respectively, with 1- and 2-year actuarial in-field local failure rates of 43% and 60% versus 66% and 83%, respectively (P=.03). There were 13 marginal failures (19%). Five of the marginal failures (38%) were located within the costomediastinal recess. Marginal failures decreased with increasing institutional experience (P=.04). Twenty-five patients (37%) had out-of-field failures. Distant failures occurred in 32 patients (48%).ConclusionsAfter hemithoracic pleural IMRT, local failure remains the dominant form of failure pattern. Patients treated with adjuvant hemithoracic pleural IMRT after P/D experience a significantly longer time to local and distant failure than patients treated with definitive pleural IMRT. Increasing experience and improvement in target delineation minimize the incidence of avoidable marginal failures.
Project description:The only registered systemic treatment for malignant pleural mesothelioma (MPM) is platinum based chemotherapy combined with pemetrexed, with or without bevacizumab. Immunotherapy did seem active in small phase II trials. In this review, we will highlight the most important immunotherapy-based research performed and put a focus on the future of MPM. PD-(L)1 inhibitors show response rates between 10 and 29% in phase II trials, with a wide range in progression free (PFS) and overall survival (OS). However, single agent pembrolizumab was not superior to chemotherapy (gemcitabine or vinorelbine) in the recent published PROMISE-Meso trial in pre-treated patients. In small studies with CTLA-4 inhibitors there is evidence for response in some patients, but it fails to show a better PFS and OS compared to best supportive care in a randomized study. A combination of PD-(L)1 inhibitor with CTLA-4 inhibitor seem to have a similar response as PD-(L)1 monotherapy. The first results of combining durvalumab (PD-L1 blocking) with cisplatin-pemetrexed in the first line are promising. Another immune treatment is Dendritic Cell (DC) immunotherapy, which is recently tested in mesothelioma, shows remarkable anti-tumor activity in three clinical studies. The value of single agent checkpoint inhibitors is limited in MPM. There is an urgent need for biomarkers to select the optimal candidates for immunotherapy among MPM patients in terms of efficacy and tolerance. Results of combination checkpoint inhibitors with chemotherapy are awaiting.
Project description:Malignant mesotheliomas are rare types of cancers that affect the mesothelial surfaces, usually the pleura and peritoneum. They are associated with asbestos exposure, but due to a latency period of more than 30 years and difficult diagnosis, most cases are not detected until they reach advanced stages. Treatment options for this tumor type are very limited and survival ranges from 12 to 36 months. This review discusses the molecular physiopathology, current diagnosis, and latest therapeutic options for this disease.
Project description:Despite advances in malignant pleural mesothelioma therapy, life expectancy of affected patients remains short. The limited efficiency of treatment options is mainly caused by inter- and intra-tumor heterogeneity of mesotheliomas. This diversity can be observed at the morphological and molecular levels. Molecular analyses reveal a high heterogeneity (i) between patients; (ii) within different areas of a given tumor in terms of different clonal compositions; and (iii) during treatment over time. The aim of the present review is to highlight this diversity and its therapeutic implications.
Project description:BackgroundThe effects of extra-pleural pneumonectomy (EPP) on survival and quality of life in patients with malignant pleural mesothelioma have, to our knowledge, not been assessed in a randomised trial. We aimed to assess the clinical outcomes of patients who were randomly assigned to EPP or no EPP in the context of trimodal therapy in the Mesothelioma and Radical Surgery (MARS) feasibility study.MethodsMARS was a multicentre randomised controlled trial in 12 UK hospitals. Patients aged 18 years or older who had pathologically confirmed mesothelioma and were deemed fit enough to undergo trimodal therapy were included. In a prerandomisation registration phase, all patients underwent induction platinum-based chemotherapy followed by clinical review. After further consent, patients were randomly assigned (1:1) to EPP followed by postoperative hemithorax irradiation or to no EPP. Randomisation was done centrally with computer-generated permuted blocks stratified by surgical centre. The main endpoints were feasibility of randomly assigning 50 patients in 1 year (results detailed in another report), proportion randomised who received treatment, proportion eligible (registered) who proceeded to randomisation, perioperative mortality, and quality of life. Patients and investigators were not masked to treatment allocation. This is the principal report of the MARS study; all patients have been recruited. Analyses were by intention to treat. This trial is registered, number ISRCTN95583524.FindingsBetween Oct 1, 2005, and Nov 3, 2008, 112 patients were registered and 50 were subsequently randomly assigned: 24 to EPP and 26 to no EPP. The main reasons for not proceeding to randomisation were disease progression (33 patients), inoperability (five patients), and patient choice (19 patients). EPP was completed satisfactorily in 16 of 24 patients assigned to EPP; in five patients EPP was not started and in three patients it was abandoned. Two patients in the EPP group died within 30 days and a further patient died without leaving hospital. One patient in the no EPP group died perioperatively after receiving EPP off trial in a non-MARS centre. The hazard ratio [HR] for overall survival between the EPP and no EPP groups was 1·90 (95% CI 0·92-3·93; exact p=0·082), and after adjustment for sex, histological subtype, stage, and age at randomisation the HR was 2·75 (1·21-6·26; p=0·016). Median survival was 14·4 months (5·3-18·7) for the EPP group and 19·5 months (13·4 to time not yet reached) for the no EPP group. Of the 49 randomly assigned patients who consented to quality of life assessment (EPP n=23; no EPP n=26), 12 patients in the EPP group and 19 in the no EPP group completed the quality of life questionnaires. Although median quality of life scores were lower in the EPP group than the no EPP group, no significant differences between groups were reported in the quality of life analyses. There were ten serious adverse events reported in the EPP group and two in the no EPP group.InterpretationIn view of the high morbidity associated with EPP in this trial and in other non-randomised studies a larger study is not feasible. These data, although limited, suggest that radical surgery in the form of EPP within trimodal therapy offers no benefit and possibly harms patients.FundingCancer Research UK (CRUK/04/003), the June Hancock Mesothelioma Research Fund, and Guy's and St Thomas' NHS Foundation Trust.