Efficacy and safety of first- or second-line irinotecan, cisplatin, and mitomycin in mesothelioma

Immunotherapy vs. Chemotherapy in Subsequent Treatment of Malignant Pleural Mesothelioma: Which Is Better?

(1) Background: Malignant pleural mesothelioma (MPM) is a rare but aggressive tumor arising from the pleural surface. For relapsed MPM, there is no accepted standard of- are for subsequent treatment. Thus, we aimed to compare the efficacy of chemotherapy, targeting drugs, and immune-checkpoint inhibitors (ICIs) as subsequent therapy for relapsed MPM. (2) Methods: The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched several acknowledged databases. Primary outcomes were defined as overall median progressive survival (mPFS) and median overall survival (mOS) in different treatment groups. Secondary outcomes were defined as objective response rate (ORR), the proportion of stable disease (SD), and progressive disease (PD). (3) Results: Ultimately, 43 articles were selected for the meta-analysis. According to the results of a pooled analysis of single-arm studies, ICIs showed a slight advantage in mOS, while chemotherapy showed a slight advantage in mPFS (mOS: 11.2 m vs. 10.39 m and mPFS: 4.42 m vs. 5.08 m for ICIs group and chemotherapy group, respectively). We identified only a few studies that directly compared the efficacy of ICIs with that of chemotherapy, and ICIs did not show significant benefits over chemotherapy based on mOS. (4) Conclusions: Based on current evidence, we considered that immunotherapy might not be superior to chemotherapy as a subsequent therapy for relapsed MPM. Although several studies investigated the efficacy of ICIs, targeting drugs, and chemotherapy in relapsed MPM, there was still no standard of care. Further randomized control trials with consistent criteria and outcomes are recommended to guide subsequent therapy in relapsed MPM and identify patients with certain characteristics that might benefit from such subsequent therapy.

Pleural mesothelioma (PM) - The status of systemic therapy

Pleural mesothelioma (PM) remains a malignancy with poor prognosis. Despite initial disappointing response rates to single-agent chemotherapy, upfront platinum and anti-folate-based combination chemotherapy has remained the backbone of treatment for PM for the last three decades. The role of maintenance chemotherapy remains unclear; switch-maintenance gemcitabine has shown improvements in progression-free but not overall survival. The addition of antiangiogenic agents to chemotherapy yielded modest improvements in survival, both upfront in combination with platinum-pemetrexed, and in the relapsed setting. Immunotherapy, particularly PD-(L)1 inhibitors, has shown important but variable effectiveness in relapsed PM when used as monotherapy, and is an important salvage treatment after first-line chemotherapy. Furthermore, the randomized phase 3 trial of ipilimumab-nivolumab versus platinum-pemetrexed chemotherapy demonstrated improved overall survival favouring ipilimumab-nivolumab (HR 0.74, 96.6% CI 0.60-0.91; p = 0.0020), establishing this regimen as the new standard first-line treatment for PM, particularly in those with non-epithelioid histology. Increased interest in PM genomics has led to development of novel personalized therapeutics, such as those targeting DNA repair and EZH2 pathways, however with variable outcomes in trials. Targeting the membrane glycoprotein mesothelin and arginine deprivation are other important strategies under ongoing investigation. The field of PM is changing and new treatments bring hope to a largely lethal and poor prognostic malignancy. Despite these developments, current challenges include understanding the role of combination and multimodality treatments, drivers of resistance to treatment, and establishing predictive biomarkers to improve patient selection and treatment sequencing.

Combined use of irinotecan and p53 activator enhances growth inhibition of mesothelioma cells

Malignant mesothelioma (MM) is an aggressive malignant neoplasm which rapidly invades pleural tissues and has a poor prognosis. Here, we explore enhancement of the effect of irinotecan [camptothecin-11 (CPT-11)] by the p53-dependent induction of carboxylesterase 2 (CES2), a CPT-11-activating enzyme, in MM. The level of CES2 mRNA was greatly increased on treatment with nutlin-3a. A combination of CPT-11 and nutlin-3a inhibited the growth of MM cells more effectively than either drug alone. Knocking down CES2 in MM cells reduced the effect of the drug combination, and its forced expression in MESO4 cells enhanced the growth inhibitory activity of CPT-11 in the absence of nutlin-3a. Enhancement of the growth inhibitory activity of CPT-11 by nutlin-3a suggests a possible new combinatorial MM chemotherapy regimen.

Efficacy and Safety of Avelumab Treatment in Patients With Advanced Unresectable Mesothelioma: Phase 1b Results From the JAVELIN Solid Tumor Trial

Importance

Patients with malignant mesothelioma whose disease has progressed after platinum and pemetrexed treatment have limited options. Anti-programmed cell death 1 (PD-1) antibodies have antitumor activity in this disease, but little is known about the activity of anti-programmed cell death ligand 1 (PD-L1) antibodies in patients with mesothelioma.

Objective

To assess the efficacy and safety of avelumab in a cohort of patients with previously treated mesothelioma.

Design, Setting, and Participants

Phase 1b open-label study (JAVELIN Solid Tumor) in patients with unresectable mesothelioma that progressed after platinum and pemetrexed treatment, enrolled at 25 sites in 3 countries between September 9, 2014, and July 22, 2015.

Interventions

Participants received avelumab, 10 mg/kg, every 2 weeks until disease progression, unacceptable toxic effects, or withdrawal from the study.

Main Outcomes and Measures

Prespecified end points included confirmed best overall response based on Response Evaluation Criteria In Solid Tumors, version 1.1; duration of response; progression-free survival (PFS); overall survival (OS); PD-L1 expression-based analyses; and safety.

Results

Of 53 patients treated with avelumab, the median age was 67 (range, 32-84) years; 32 (60%) were male. As of December 31, 2016, median follow-up was 24.8 (range, 16.8-27.8) months. Twenty patients (38%) had 3 or more previous lines of therapy (median, 2; range, 1-8). The confirmed objective response rate (ORR) was 9% (5 patients; 95% CI, 3.1%-20.7%), with complete response in 1 patient and partial response in 4 patients. Responses were durable (median, 15.2 months; 95% CI, 11.1 to not estimable months) and occurred in patients with PD-L1-positive tumors (3 of 16; ORR, 19%; 95% CI, 4.0%-45.6%) and PD-L1-negative tumors (2 of 27; ORR, 7%; 95% CI, 0.9%-24.3%) based on a 5% or greater PD-L1 cutoff. Disease control rate was 58% (31 patients). Median PFS was 4.1 (95% CI, 1.4-6.2) months, and the 12-month PFS rate was 17.4% (95% CI, 7.7%-30.4%). Median OS was 10.7 (95% CI, 6.4-20.2) months, and the median 12-month OS rate was 43.8% (95% CI, 29.8%-57.0%). Five patients (9%) had a grade 3 or 4 treatment-related adverse event, and 3 (6%) had a grade 3 or 4 immune-related, treatment-related adverse event. There were no treatment-related deaths.

Conclusions and Relevance

Avelumab showed durable antitumor activity and disease control with an acceptable safety profile in a heavily pretreated cohort of patients with mesothelioma.

Trial Registration

ClinicalTrials.gov identifier: NCT01772004.

Emerging therapies in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare cancer of the pleural surfaces frequently related to asbestos exposure. It is characterized by a poor prognosis even for patients treated with trimodality therapy, including surgery, chemotherapy and radiotherapy. Moreover, the majority of patients are not candidates for surgery due to disease advanced stage or medical comorbidities. For these patients, the survival rate is even lower and few therapeutic options are currently available. Nevertheless, many interesting novel approaches are under investigation, among which immunotherapy represents one of the most promising emerging strategies. In this review, we will discuss the role of new therapeutic options, particularly immunotherapy, and present the results of the most important and promising clinical trials.

Interplay of non-coding RNAs and approved antimetabolites such as gemcitabine and pemetrexed in mesothelioma

Gemcitabine and pemetrexed are clinically approved antimetabolites for the therapy of mesothelioma diseases. These drugs are often applied in combination with platinum complexes and other drugs. The activity of antimetabolites depended on the expression levels of certain non-coding RNAs, in particular, of small microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). The development of tumor resistance towards antimetabolites was regulated by non-coding RNAs. An overview of the interplay between gemcitabine/pemetrexed antimetabolites and non-coding RNAs in mesothelioma is provided. Further to this, various non-coding RNA-modulating agents are discussed which displayed positive effects on gemcitabine or pemetrexed treatment of mesothelioma diseases. A detailed knowledge of the connections of non-coding RNAs with antimetabolites will be constructive for the design of improved therapies in future.

Malignant Pleural Mesothelioma: Is Tailoring the Second-Line Therapy Really "Raising the Bar?"

OPINION STATEMENT

Unresectable or relapsed malignant pleural mesothelioma (MPM) has dismal prognosis. First-line combination therapy with pemetrexed and a platinum analog allows a modest survival benefit, while no clear therapeutic options exist for the second-line therapy. In this setting, pemetrexed seems to be the most active drug; however, the inclusion in front-line treatment limits its use in further lines. Nevertheless, rechallenge with one or both drugs used in first-line remains a feasible strategy for responder patients. Alternatively, only few cytotoxic drugs have demonstrated a mild activity in refractory MPM. Among other options, targeted therapy has unfortunately produced disappointing results as salvage treatment probably due to the lack of a clear understanding of the tumor biology. In contrast, recent data suggest moderate efficacy and mild toxicity of immunotherapy also for the treatment of MPM. The combination of checkpoint inhibitors with chemotherapy or other immunological agents seems promising and could really "raise the bar" in this setting.

The use of patient-reported outcome measures (PROMs) in the management of malignant pleural mesothelioma: a descriptive literature survey

Background

Malignant pleural mesothelioma (MPM) remains a highly symptomatic and aggressive malignancy. The treatment options are for most patients limited to palliative chemotherapy and best supportive care. Therefore, the use of patient-reported outcome measures (PROMs) is recommended for the improvement of the quality of care. The aim of this literature survey is to provide an up to date review of the use of PROMs in mesothelioma. A concise comparison is made of the identified instruments.

Methods

We searched PubMed, Web of Science and Google Scholar for the use of PROMs in MPM. Quality of the study and risk of bias were assessed using the appraisal tools recommended by the Dutch Cochrane Center.

Results

A total of 31 articles on PROMs in MPM were identified that met the inclusion criteria and a total of 14 instruments. The instruments are categorized in generic (n=2), cancer-specific (n=4), lung cancer-specific (n=3), mesothelioma-specific (n=2) and symptom-specific (n=3). They were mostly used in clinical trials.

Conclusions

PROMs have the potential to improve the management of MPM. No particular instrument is specifically recommended, although there is a preference for patient-reported disease-specific instruments encompassing the concept of health-related quality of life (hrQoL) and relevant symptoms. Such instruments are the EORTC QLQ-LC13, LCSS-Meso and FACT-L, which measure the impact of malignant mesothelioma and its treatment on patients. Assessments should be made on baseline and post-treatment. The frequency of assessments should be further evaluated in this population.

A systematic review and meta-analysis of second-line therapies for treatment of mesothelioma

INTRODUCTION

Advanced malignant pleural mesothelioma (MPM) is generally treated with platinum/pemetrexed-based first-line therapy. Once the disease progresses, evidence for the efficacy of palliative treatments is lacking, and platinum re-challenge or single-agent chemotherapy are commonly used. To assess the effects of cytostatic or targeted therapy for treating MPM, we performed a systematic review and meta-analysis.

MATERIAL AND METHODS

PubMed, the Cochrane Library, and Embase databases were searched to identify published articles on second-line treatments for recurrent or advanced mesothelioma. Inclusion criteria were publication in the English language, describing clinical trials with 20 or more patients, and evaluability for efficacy and for receiving second-line systemic therapies. Data were pooled using number of events/number of evaluable patients, median overall survival (OS) and progression-free survival (PFS), according to a fixed or random effect model. Pooled median OS was the primary endpoint.

RESULTS

A total of 49 eligible studies (n = 3938 patients; range, 12-400) were identified. Median progression-free survival (PFS) was 3.4 months (95%CI 2.87-3.93). Median pooled OS was 7.86 (95%CI 7.01-8.72). The pooled overall response rate (ORR) was 8.63% (95%CI 6-11.26), and the pooled disease control rate (DCR) was 54.8% (95%CI 48.9-60.6). Median pooled OS with platinum- and pemetrexed-based chemotherapy were 7.93 and 7.78 months, respectively.

CONCLUSIONS

There remains uncertainty about the ideal second-line agent for MPM. Based on this meta-analysis, palliative chemotherapy or other experimental agents can be considered for patients with MPM who desire further treatment after their disease has progressed, during or after first-line therapy.

Medical treatment of malignant pleural mesothelioma relapses

There are not established treatments for patients with advanced malignant pleural mesothelioma that progressed after first-line chemotherapy with cisplatin and pemetrexed. Retrospective analyses suggest a possible role for rechallenge with pemetrexed for selected patients. Phase II trials demonstrate a modest efficacy of vinorelbine monotherapy with a response rate ranging between 0% and 18% and a tolerable toxicity profile. Combination schedules, despite an increased toxicity, fail to demonstrate an improved efficacy. To date, genome wide analyses did not show molecular targets suitable for therapy and biological drugs did not exert a significant efficacy in clinical trials. Immunotherapy has given a hint of efficacy in early clinical trials but definitive evaluations are still ongoing.

Chemotherapy treatment in malignant pleural mesothelioma: a difficult history

Malignant pleural mesothelioma (MPM) is a rare neoplasm that typically arises from mesothelial surfaces of the pleural cavity. Despite treatment improvements, it carries a dismal prognosis. The majority of patients either have unresectable disease or are not candidates for surgery due to medical comorbidities or old age. For such patients, chemotherapy (CT) represents the gold-standard treatment. To date, combination CT with cisplatin plus pemetrexed represents the most widely used regimen in first-line setting for patients with unresectable MPM. Other first-line options are currently available, including the use of raltitrexed instead of pemetrexed combined with platinum. In this review, we discuss the role of CT in MPM mainly focusing on the results of the trials conducted in first-line setting.

Advances in systemic therapy for malignant mesothelioma: future perspectives

Malignant mesothelioma is a rare and aggressive form of cancer affecting the mesothelium. This mainly occupational disease is becoming more common in those countries where asbestos has been used for industrial applications. Notwithstanding the progress made in the field, patients do not survive more than 12 months on average with standard treatment. With the advent of next generation sequencing, it is now possible to study the mutational landscape of each tumor with the aim of identifying the genetic aberrations driving tumorigenesis. This review encompasses the latest research in the field, with particular attention to new chemotherapy combinatorial regimens, molecular targets and immunotherapies, providing a comprehensive picture of the current and future treatment options for malignant mesothelioma patients.

Sensitization of mesothelioma cells to platinum-based chemotherapy by GSTπ knockdown

It is predicted that the incidence of mesothelioma will increase and thus it is important to find new ways to treat this chemoresistant tumor. Glutathione-S-Transferase π (GSTπ) is found at significant levels in mesotheliomas and thus attenuating its intracellular levels may provide a means of sensitizing mesothelioma cells to chemotherapy. GSTπ knockdowns were therefore prepared with shRNA (less off-target effects) employing two cell lines (211H, H2452) that were typed by immunohistochemistry to be of mesothelial origin. The knockdowns exhibited a decrease in both total GST enzyme activity and GSTπ protein levels as well as an increase in both glutathione levels and sensitivity to cis and oxaliplatin. Cisplatin treatment of the knockdowns increased ROS levels significantly (as compared to the parental cells) and produced activation of the JNK/p38 pathways and activating transcription factor (ATF2). The degree of activation and increase in ROS appeared to correlate with the cell line's sensitivity to cisplatin. Treatment with N-Acetyl Cysteine decreased ROS production and JNK/p38 phosphorylation but had minimal affect on ATF2 suggesting a direct interaction of GTPπ with this transcription factor. Oxaliplatin treatment produced only minimal changes in ROS levels and activation of the JNK/p38 pathway. Recently, new methods of siRNA delivery (nanoparticles) have been shown to be effective in decreasing the levels of target proteins in humans including candidate genes involved in drug resistance - thus this approach may have promise in sensitizing cisplatin-resistant tumors to chemotherapy.

Vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-platinum chemotherapy is the standard first-line treatment of unresectable malignant pleural mesothelioma (MPM). At progression, patients are generally selected to experimental trials, when available, or, in every-day clinical practice, they are offered second-line chemotherapy. The optimal treatment has not yet been defined. The aim of this retrospective, single-center study was to evaluate the activity and toxicity of vinorelbine administered to a consecutive series of pemetrexed-pretreated MPM patients.

METHODS

Vinorelbine 25 mg/m(2) was administered intravenously as a single agent on days 1, 8 every three weeks, either as second-line (2L) or further-line (>2L) therapy. Treatment was repeated for a maximum of 6 cycles, until progression, or unacceptable toxicity.

RESULTS

Fifty-nine patients were included in this analysis. Vinorelbine was given to 34 patients as 2L, and to 25 as > 2L treatment. The median age was 69 years (range 45-80). Forty-two patients (71.2%) had a good EORTC prognostic score. Partial response was observed in 9 (15.2%) cases, stable disease in 20 (33.9%). The overall disease control rate (DCR) was 49.1%. Median progression-free survival (PFS) and overall survival (OS) were 2.3 and 6.2 months, respectively. ECOG performance status (PS) (HR(0 vs. 1-2) 0.50; 95%CI: 0.3-0.8; p = 0.014) and PFS ≥ 6 months following first-line (FL) chemotherapy (HR(FL-PFS>6 ms vs. <6 ms) 0.50; 95%CI: 0.3-0.9; p = 0.031) were significantly associated to OS in multivariate analysis. No difference was observed in terms of DCR, PFS, and OS in relation to age, histology, sex, line of vinorelbine therapy, or response to FL treatment. Hematological toxicity was acceptable, with grade 3/4 neutropenia occurring in 5 (8.4%) patients, and there were no cases of febrile neutropenia. The main non-hematological toxicities were grade 2 fatigue in 17 (28.8%) and constipation in 7 (11.8%) patients.

CONCLUSIONS

Vinorelbine was moderately active in pemetrexed-pretreated MPM patients, with an acceptable toxicity profile, particularly in patients with ECOG-PS0 and FL-PFS ≥ 6 months.

Glutathione S-transferase P1-1 as a target for mesothelioma treatment

Malignant pleural mesothelioma is a poorly responsive tumor known to overexpress the phase II detoxification enzyme glutathione-S-transferase, which catalyzes the conjugation between glutathione and platinum(II)-containing drugs. Therefore, we evaluated the effect of the strong glutathione S-transferase inhibitor NBDHEX on human mesothelioma cell lines (MSTO-211H, MPP89, MM-B1 and Mero 48a) featuring the most common mesothelioma phenotypes: epithelioid and biphasic. Even though a different response to NBDHEX was observed, the molecule was very effective on all cell lines tested, triggering a sustained activation of both JNK and p38, followed by caspase activation and apoptosis. NBDHEX also caused severe oxidative stress in the MPP89 cells and, to a lesser extent, in the MMB1 cells, while it did not cause a significant redox imbalance in the other cell lines. The efficacy of the drug was found to be comparable or even higher than that of cisplatin. Moreover, it showed synergistic or additive effects when used in combination with cisplatin. In conclusion, NBDHEX was effective on mesothelioma cell lines, with IC(50) values in the low micromolar range (IC(50) between 1 and 4 μM). These findings indicate that NBDHEX, alone or in combination with cisplatin, is a promising new strategy for treating this rare and aggressive malignancy.

Advanced diffuse malignant peritoneal mesothelioma responding to palliative chemotherapy

A 64-year-old man diagnosed with advanced malignant peritoneal mesothelioma by laparoscopic biopsy was treated with systemic chemotherapy. The patient underwent first-line chemotherapy with pemetrexed plus cisplatin for 11 months, then second-line chemotherapy with gemcitabine plus vinorelbine for 6 months, and third-line chemotherapy with CPT-11 for 4 months. After third-line chemotherapy failed, he received palliative treatment. Although the tumor continued to grow, and he died 24 months after initiation of treatment, chemotherapy prolonged the survival time and improved his quality of life.

Second-line chemotherapy in malignant pleural mesothelioma: results of a retrospective multicenter survey

The pemetrexed-cisplatin chemotherapy is standard of care in first-line (FL) treatment of malignant pleural mesothelioma (MPM). The second-line (SL) chemotherapy is considered, but the optimal treatment has not been defined yet. The aim of this study was to evaluate the clinical outcomes of SL-therapy in a series of MPM-patients included in a retrospective multicenter database. Clinical records of MPM-patients who received SL-treatment from 1996 to 2008 were reviewed. Study endpoints were response, overall-survival (OS), and progression-free-survival (PFS) for SL, stratified for patient characteristics, FL-outcomes, and type of SL. Out of 423 patients, 181 with full clinical data were identified. Patients' characteristics: median-age 64 years (range: 36-85); male gender 115 (63.5%); good EORTC-score 109 (60.2%); epithelial histology 135 (74.6%). After FL, 147 (81.2%) patients achieved disease-control (DC) and 45 had a time-to-progression≥12 months (TTP≥12). After SL, 95 patients (52.6%) achieved DC (21 response; 74 stable-disease); median PFS and OS were 4.3 and 8.7 months, respectively. According to multivariate analysis, DC after SL-therapy was significantly related to pemetrexed-based treatment (OR: 2.46; p=0.017) and FL-TTP≥12 (OR: 3.50; p=0.006). PFS was related to younger age (<65 years) (HR: 0.70; p=0.045), ECOG-PS0 (HR: 0.67; p=0.022), and FL-TTP≥12 (HR: 0.45; p<0.001). OS was significantly related to ECOG-PS0 (HR: 0.43; p<0.001) and to FL-TTP≥12 (HR: 0.54; p=0.005). In pemetrexed pre-treated patients, re-treatment with a pemetrexed/platinum combination significantly reduced the risk-of-death than pemetrexed alone (HR: 0.11; p<0.001). In conclusion, SL-chemotherapy seems to be active in MPM-patients, particularly in younger patients with ECOG-PS0 and prolonged TTP after FL-pemetrexed-based chemotherapy. In selected patients, re-challenge with pemetrexed-based regimens, preferentially associated with platinum-compound, appears to be an option for SL-setting. Considering the important limitations of this study, due to retrospective nature and the possible selection bias, prospective clinical trials are warranted to clarify these issues.

Investigational approaches for mesothelioma

Malignant pleural mesothelioma (MPM) is a rare, aggressive tumor with a poor prognosis. In view of the poor survival benefit from first-line chemotherapy and the lack of subsequent effective treatment options, there is a strong need for the development of more effective treatment approaches for patients with MPM. This review will provide a comprehensive state of the art of new investigational approaches for mesothelioma. In an introductory section, the etiology, epidemiology, natural history, and standard of care treatment for MPM will be discussed. This review provide an update of the major clinical trials that impact mesothelioma treatment, discuss the impact of novel therapeutics, and provide perspective on where the clinical research in mesothelioma is moving. The evidence was collected by a systematic analysis of the literature (2000-2011) using the databases Medline (National Library of Medicine, USA), Embase (Elsevier, Netherlands), Cochrane Library (Great Britain), National Guideline Clearinghouse (USA), HTA Database (International Network of Agencies for Health Technology Assessment - INAHTA), NIH database (USA), International Pleural Mesothelioma Program - WHOLIS (WHO Database), with the following keywords and filters: mesothelioma, guidelines, treatment, surgery, chemotherapy, radiotherapy, review, investigational, drugs. Currently different targeted therapies and biologicals are under investigation for MPM. It is important that the molecular biologic research should first focus on mesothelioma-specific pathways and biomarkers in order to have more effective treatment options for this disease. The use of array technology will be certainly an implicit gain in the identification of new potential prognostic or biomarkers or important pathways in the MPM pathogenesis. Probably a central mesothelioma virtual tissue bank may contribute to the ultimate goal to identify druggable targets and to develop personalized treatment for the MPM patients.

Chemotherapy for malignant pleural mesothelioma

OPINION STATEMENT

All MPM patients with a good performance status should be considered for enrollment on clinical trials. With that said, the standard frontline therapy for fit MPM patients remains an antifolate/platinum doublet, based on large, well powered randomized clinical trials that showed not only a survival benefit for antifolate/platinum regimens but also improvements in quality of life and/or symptoms. For less fit patients, single agents can be used as frontline therapy. In the second line setting, there is benefit from retreatment with single agent pemetrexed after prior exposure to that agent, as well as after exposure to other chemotherapeutic agents. Other single chemotherapy agents and combinations are viable options for fit patients who have had relatively long time to progression after their frontline therapy. Additionally, several prognostic scales designed for MPM (CALGB and EORTC) provide additional means to better select patients for frontline and second line chemotherapy.

Phase II study of gemcitabine plus docetaxel as second-line treatment in malignant pleural mesothelioma: a single institution study

OBJECTIVE

The combinations of cisplatin-pemetrexed and cisplatin-gemcitabine are considered the standard systemic therapy for malignant pleural mesothelioma (MPM), which is a rapidly progressive tumor. The purpose of the present study is to evaluate the efficacy, safety, and clinical benefit of the gemcitabine plus docetaxel regimen in the second-line treatment of this disease.

PATIENTS AND METHODS

A total of 37 patients with MPM were treated with the combination of docetaxel (80 mg/m) and gemcitabine (1000 mg/m) on day 1 and 14 of a 28-day cycle. The regimen was repeated for a maximum of 6 cycles or until disease progression or unacceptable toxicity.

RESULTS

There was partial response of the disease in 7 patients (18.9%), whereas it remained stable in 23 patients (62.2%) and progressed in 7 patients (18.9%). The median time to disease progression was 7 months (range: 5.8-8.2 months) with a mean survival of 16.2 months (range: 13-19.3 months).

CONCLUSION

The biweekly administration of docetaxel and gemcitabine, along with granulocyte colony-stimulating factor support, constitutes a safe, tolerable, and convenient regimen for the treatment of MPM, suggesting that this combination may be a viable option, especially in previously treated patients.

[Guidelines of the European Respiratory Society and the European Society of Thoracic Surgeons for the management of malignant pleural mesothelioma]

恶性胸膜间皮瘤（malignant pleural mesothelioma, MPM）是一种罕见肿瘤，但发病率正逐渐上升，且预后较差。2008年，欧洲呼吸学会（European Respiratory Society, ERS）和欧洲胸外科医师学会（European Society of Thoracic Surgeons, ESTS）特别工作组召集各方专家计划制定MPM诊治经验及更新指南。

为了使MPM得到及时准确的诊断，专家推荐对患者实施胸腔镜检查，有手术禁忌和胸腔粘连的病例除外。约10%的病例采用标准染色方法无法获得满意的结果。因此我们推荐在胸膜活检的基础上，采用特异性免疫组化标志物。由于目前缺乏一个统一的、切实有效的分期系统，我们推荐应用最新的TNM分期，并且提出三个阶段的治疗前评估。在MPM的治疗中，患者的体力状态评分和组织亚型是目前唯一的、具有重要临床价值的预后因素。在临床试验中，应对其它潜在因素进行初步探讨并予以报道。MPM对化疗高度耐受，仅有少数患者可接受根治性手术。本文对新的治疗方法和策略进行了综述。

目前由于最佳综合治疗的资料有限，适合采用多种方案联合治疗策略的患者应被纳入专业机构的前瞻性试验中。

[Second-line therapy in patients with malignant pleural mesothelioma. A French retrospective study (2005-2006)]

BACKGROUND

The role of second-line chemotherapy (SLC) has still not been established in malignant pleural mesothelioma (MPM) but SLC is increasingly used because many patients are still fit at the time of the progression of the disease.

METHODS

In this retrospective study, the authors reviewed their experience with SLC in pemetrexed-pretreated patients with MPM at two French thoracic oncology units (institut Gustave-Roussy, Villejuif, and hôpital d'Instruction des Armées Percy, Clamart).

RESULTS

Between January 2005 and December 2006, 84 consecutive patients with progressing MPM after pemetrexed chemotherapy were enrolled. Forty-four patients received an SLC. There were 30 men and 14 women. The median age was 58 years (range: 34 to 76 years). Most patients had a performance status (PS) less than or equal to 1 (82%) and an epithelial histological subtype (91 %). The median time to progression (TTP) after first-line chemotherapy was 6.1 months. The SLC was a pemetrexed therapy in 21 patients and a new regime in 20 patients (gemcitabine alone or with oxaliplatin). The other three patients were enrolled in a phase I study. According to the Recist criteria, a partial response was observed in four patients and the disease was stabilised in six patients after SLC. The median TTP after SLC was 3.8 months. The median survival was 12.2 months (range: 2 to 72 months). Four of these 44 patients then received third-line (4.8 %) and two received fourth-line therapy (2.4 %).

CONCLUSIONS

This experience indicates the feasibility of administering SLC in patients with MPM who are healthy at the time of the progression of the disease. The optimal treatment has not been defined to date and prospective trials are needed.

Systemic treatments for mesothelioma: standard and novel

Systemic therapy is the only treatment option for the majority of mesothelioma patients, for whom age, co-morbid medical illnesses, non-epithelial histology, and locally advanced disease often preclude surgery. For many years, chemotherapy had a minimal impact on the natural history of this cancer, engendering considerable nihilism. Countless drugs were evaluated, most of which achieved response rates below 20% and median survival of <1 year. Several factors have hampered the evaluation of systemic regimens in patients with mesothelioma. The disease is uncommon, affecting only about 2500 Americans annually. Thus, most clinical trials are small, and randomized studies are challenging to accrue. There is significant heterogeneity within the patient populations of these small trials, for several reasons. Since all of the staging systems for mesothelioma are surgically based, it is almost impossible to accurately determine the stage of a patient who has not been resected. Patients with very early stage disease may be lumped together with far more advanced patients in the same study. The disease itself is heterogenous, with many different prognostic factors, most notably three pathologic subtypes—epithelial, sarcomatoid, and biphasic—that have different natural histories, and varying responses to treatment. Finally, response assessment is problematic, since pleural-based lesions are difficult to measure accurately and reproducibly. Assessment criteria often vary between trials, making some cross-trial comparisons difficult to interpret. Despite these limitations, in recent years, there has been a surge of optimism regarding systemic treatment of this disease. Several cytotoxic agents have been shown to generate reproducible responses, improve quality of life, or prolong survival in mesothelioma. Drugs with single-agent activity include pemetrexed, raltitrexed, vinorelbine, and vinflunine. The addition of pemetrexed or raltitrexed to cisplatin prolongs survival. The addition of cisplatin to pemetrexed, raltitrexed, gemcitabine, irinotecan, or vinorelbine improves response rate. The combination of pemetrexed plus cisplatin is considered the benchmark front-line regimen for this disease, based on a phase III trial in 456 patients that yielded a response rate of 41% and a median survival of 12.1 months. Vitamin supplementation with folic acid is essential to decrease toxicity, though recent data suggests that there may be an optimum dose of folic acid that should be administered; higher doses may diminish the effectiveness of pemetrexed. There are also several unresolved questions about the duration and timing of treatment with pemetrexed that are the subject of planned clinical trials. It is essential to recognize that the improvements observed with the pemetrexed/cisplatin combination, though real, are still modest. Other active drugs or drug combinations may be more appropriate for specific individuals, and further research is still needed to improve upon these results. Since the majority of mesotheliomas in the United States occur in the elderly, non-cisplatin-containing pemetrexed combinations may be more appropriate for some patients. Now that effective agents have been developed for initial treatment, several classical cytotoxic drugs and many novel agents are being evaluated in the second-line setting. These include drugs targeted against the epidermal growth factor, platelet-derived growth factor, vascular endothelial growth factor, src kinase, histone deacetylase, the proteasome, and mesothelin. Given the progress made in recent years, there is reason to believe that more effective treatments will continue to be developed.

The efficacy and safety of weekly vinorelbine in relapsed malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rapidly progressive invariably lethal tumor. Treatment options remain limited and the outcome in relapsed disease is poor warranting new therapeutic options. Following our previous experience in the first-line setting, we conducted a phase 2 open-label non-comparative study to assess the safety and efficacy of weekly vinorelbine chemotherapy, each cycle consisting of 30 mg/m(2) for 6 weeks, in patients with previous exposure to chemotherapy. In 63 individuals with relapsed MPM who had not received previous vinorelbine, we observed an objective response rate of 16% and an overall survival of 9.6 months (95% confidence interval 7.3-11.8 months). The main grade III/IV toxicity observed was neutropenia and toxicity was similar to weekly vinorelbine when used in the first-line setting. Weekly vinorelbine appeared to have a reasonable response rate with an acceptable toxicity profile in the second-line treatment of MPM. Its use should be prospectively evaluated in a randomised trial in the first or second-line therapy of MPM.

Gemcitabine and vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-cisplatin chemotherapy is the standard of care in the first-line treatment of unresectable malignant pleural mesothelioma (MPM). Second-line cytotoxic therapy is considered for a growing group of patients, but the optimal treatment has not been defined to date. Gemcitabine and vinorelbine have shown activity in the first-line setting. The objective of this study was to evaluate the activity and toxicity of the gemcitabine-vinorelbine combination in pemetrexed-pretreated patients with MPM.

METHODS

From January 2004 to September 2006, 30 consecutive patients who were pretreated with pemetrexed with or without a platinum-derivative were enrolled. Gemcitabine 1000 mg/m(2) and vinorelbine 25 mg/m(2) were administered intravenously on Days 1 and 8 every 3 weeks. Treatment was repeated for a maximum of 6 cycles or until progression or unacceptable toxicity.

RESULTS

A partial response was observed in 3 patients (10%; 95% confidence interval [CI], 2.1-26.5%), and 10 patients (33.3%; 95% CI, 17.3-52.8%) had stable disease after treatment. Overall, 13 patients (43.3%; 95% CI, 25.5-62.6%) achieved disease control. The median time to progression was 2.8 months (range, 0.6-12.1 months), and the median survival was 10.9 months (range, 0.8-25.3 months). Hematologic toxicity was acceptable, with grade 3 or 4 neutropenia occurring in 11% of patients and thrombocytopenia occurring in 4% of patients; no case of febrile neutropenia was observed. Nonhematologic toxicity generally was mild.

CONCLUSIONS

The gemcitabine and vinorelbine combination was moderately active and had an acceptable toxicity profile in pemetrexed-pretreated patients with MPM. The role of second-line treatment in MPM needs to be evaluated in prospective trials in large series of patients who are stratified according to previous treatment and prognostic factors.

Advances in the systemic therapy of malignant pleural mesothelioma

Malignant pleural mesothelioma is an aggressive thoracic malignancy associated with exposure to asbestos, and its incidence is anticipated to increase during the first half of this century. Chemotherapy is the mainstay of treatment, yet sufficiently robust evidence to substantiate the current standard of care has emerged only in the past 5 years. This Review summarizes the evidence supporting the clinical activity of chemotherapy, discusses the use of end points for its assessment and examines the influence of clinical and biochemical prognostic factors on the natural history of malignant pleural mesothelioma. Early-phase clinical trials of second-line and novel agents are emerging from an increased understanding of mesothelioma cell biology. Coupled with high-quality translational research, such developments have real potential to improve the outlook of patients at a time of increasing incidence.

Management options for malignant pleural mesothelioma: clinical and cost considerations

Malignant pleural mesothelioma (MPM) is a resistant form of lung cancer that is often related to prior asbestos exposure. While surgical resection and radiotherapy techniques have been refined in recent years, neither has been proven to significantly extend patient survival compared with untreated controls. Until the release of pemetrexed in 2004, even combination chemotherapy regimens often resulted in a response rate of <20%. A recent phase III trial documented a 41.3% response rate for cisplatin plus pemetrexed. In the future, new multimodality regimens featuring novel targeted therapies directed against molecular targets, such as the vascular endothelial growth factor, hold the greatest promise for improved outcomes in MPM. The standard radiographic assessment of response to MPM therapy remains a poor surrogate for clinically relevant endpoints such as median survival. Furthermore, it is not currently known whether aggressive multimodality treatment for MPM will improve survival or quality of life above and beyond symptomatic care. Ongoing clinical trials are comparing chemotherapy and surgery with supportive care in an effort to define the role of different therapies in MPM. MPM treatment is a costly public health issue; after efficacy is proven, additional studies are needed to measure the cost effectiveness of MPM treatment regimens.

Phase II trial of irinotecan, cisplatin and mitomycin for relapsed small cell lung cancer

There is no standard therapy for relapsed small cell lung cancer (rSCLC). We evaluated the efficacy and toxicity of a new triplet consisting of irinotecan (100 mg/m(2) Days 1 and 15 q28), cisplatin (40 mg/m(2) Days 1 and 15 q28) and mitomycin (6 mg/m(2) d1 q28) administered to a maximum of 6 cycles in individuals with rSCLC that had relapsed following first line treatment. Partial remissions were observed in 35% and progression in 30% of patients. Progression free survival measured 4.5 months (95% CI 0.8-8.2) and overall survival was 7.8 months (95% CI 5.3-10.3). QoL showed improvement in activity symptoms and stabilization of physical symptoms. As IPM was a well-tolerated regimen with activity in rSCLC, a phase III trial comparing this triplet with other regimens in this setting is warranted.