Malignant pleural mesothelioma and the Society of Thoracic Surgeons Database: an analysis of surgical morbidity and mortality

The Role of Surgery in Pleural Mesothelioma

Surgery plays a central role in the diagnosis, staging, and management of pleural mesothelioma. Achieving an accurate diagnosis through surgical intervention and identifying the specific histologic subtype is crucial for determining the appropriate course of treatment. The histologic subtype guides decisions regarding the use of chemotherapy, immunotherapy, or multimodality treatment. The goal of surgery as part of multimodality treatment is to accomplish macroscopic complete resection with the eradication of grossly visible and palpable disease. Over the past two decades, many medical centers worldwide have shifted from performing extra-pleural pneumonectomy (EPP) to pleurectomy decortication (PD). This transition is motivated by the lower rates of short-term mortality and morbidity associated with PD and similar or even better long-term survival outcomes, compared to EPP. This review aims to outline the role of surgery in diagnosing, staging, and treating patients with pleural mesothelioma.

Optimal surgery for resectable malignant pleural mesothelioma in the setting of multimodality treatment

The surgical treatment of malignant pleural mesothelioma (MPM) involves procedures to achieve macroscopic complete resection, depending on the patient's condition. We reviewed the evolution of surgical approaches for resectable MPM. Since surgery is no more than a single step in the set of processes in multimodality treatment (MMT), we concluded that these procedures should give precedence to lung preservation and minimize resection whenever possible. Postoperative quality of life must be prioritized when the patient can receive appropriate adjuvant therapy.

Contemporary issues in the surgical management of pleural mesothelioma

The surgical management of pleural mesothelioma (PM) can be divided into diagnostic, staging, palliation, and cytoreductive surgery. In the cytoreductive surgical setting, the combination of different treatment modalities has led to better outcomes than surgery alone. The scarcity of high-quality studies has led to heterogeneity in management of PM across the mesothelioma treatment centers. Here, we review the literature regarding the most important open questions and ongoing clinical trials.

Activation of Adaptive and Innate Immune Cells via Localized IL2 Cytokine Factories Eradicates Mesothelioma Tumors

PURPOSE

IL2 immunotherapy has the potential to elicit immune-mediated tumor lysis via activation of effector immune cells, but clinical utility is limited due to pharmacokinetic challenges as well as vascular leak syndrome and other life-threatening toxicities experienced by patients. We developed a safe and clinically translatable localized IL2 delivery system to boost the potency of therapy while minimizing systemic cytokine exposure.

EXPERIMENTAL DESIGN

We evaluated the therapeutic efficacy of IL2 cytokine factories in a mouse model of malignant mesothelioma. Changes in immune populations were analyzed using time-of-flight mass cytometry (CyTOF), and the safety and translatability of the platform were evaluated using complete blood counts and serum chemistry analysis.

RESULTS

IL2 cytokine factories enabled 150× higher IL2 concentrations in the local compartment with limited leakage into the systemic circulation. AB1 tumor burden was reduced by 80% after 1 week of monotherapy treatment, and 7 of 7 of animals exhibited tumor eradication without recurrence when IL2 cytokine factories were combined with anti-programmed cell death protein 1 (aPD1). Furthermore, CyTOF analysis showed an increase in CD69+CD44+ and CD69-CD44+CD62L- T cells, reduction of CD86-PD-L1- M2-like macrophages, and a corresponding increase in CD86+PD-L1+ M1-like macrophages and MHC-II+ dendritic cells after treatment. Finally, blood chemistry ranges in rodents demonstrated the safety of cytokine factory treatment and reinforced its potential for clinical use.

CONCLUSIONS

IL2 cytokine factories led to the eradication of aggressive mouse malignant mesothelioma tumors and protection from tumor recurrence, and increased the therapeutic efficacy of aPD1 checkpoint therapy. This study provides support for the clinical evaluation of this IL2-based delivery system. See related commentary by Palanki et al., p. 5010.

The Effects of Preserving the Diaphragm on Early and Late Outcome of Lung-Sparing Radical Surgery for Malignant Pleural Mesothelioma

BACKGROUND

The accepted aim of radical surgery for malignant pleural mesothelioma (MPM) is the achievement of macroscopic complete resection (MCR) whilst reducing perioperative morbidity by preserving normal tissue. Whilst preservation of the lung by pleurectomy/decortication (PD) has become widely utilised, there remains debate regarding the management of the diaphragm. Muscle-sparing complete excision of the diaphragmatic pleura is technically challenging; thus, surgeons may proceed to extended PD with phrenectomy and possible increased morbidity or to preserve the diaphragmatic pleura at the expense of MCR with potential survival deficit. We aimed to evaluate the effects of an intentional change in protocol to diaphragm-sparing PD whilst maintaining MCR as the treatment of choice for MPM.

METHODS

In a series of 136 patients (111M:25F, median age 68(63-73) years) undergoing radical surgery for MPM, we identified 28 patients (22M:6F, median age 67(60-71) years) in whom MCR was achieved without phrenectomy (PD group). We compared their perioperative outcomes and survival with a historical control group of 18 patients (18M:0F, median age 69(57-78) years) in whom MCR had been achieved with phrenectomy (EPD group) but in whom there was no histological evidence of diaphragm muscle invasion and who, in retrospect, could have undergone muscle-sparing MCR if this procedure had been attempted.

RESULTS

There was no significant intergroup difference in demographics or tumour cell type; the majority of both groups were found to be epithelial (PD 85.7%, EPD 77.8%). The EPD group was found to be more locally advanced (T3 55.56%) than the PD group (T1 46.43%) (p = 0.03). All the following parameters were significantly reduced after PD compared to EPD: operative time (188 vs. 220 min, p = 0.007); duration of air leak (5 vs. 10 days, p = 0.001), duration of inotrope (p = 0.009) and post-operative hospital stay (8 vs. 13 days, p = 0.034). There were no significant differences (p = 0.123) in overall survival (OS) between the two groups, but the median survival in the PD group had not been reached at a median follow up of 33.9 (24.2-46) months.

CONCLUSIONS

A surgical strategy of attempting to spare the diaphragm whilst still achieving MCR wherever possible is justified by improved perioperative outcomes without compromising OS.

Single-Center 20-Year Experience in Surgical Treatment of Malignant Pleural Mesothelioma

Objectives: We examined a series of malignant pleural mesothelioma (MPM) patients who consecutively underwent surgery in our institution during the last 20 years. Across this period, we changed our surgical approach to MPM, adopting extended pleurectomy and decortication (eP/D) instead of extrapleural pneumonectomy (EPP). In this study, we compare the perioperative outcomes and long-term survival of patients who underwent EPP vs. eP/D. Methods: A retrospective analysis was carried out of all the MPM patients identified from our departmental database who underwent EPP or P/D from 2000 to 2021. Clavien−Dindo criteria was adopted to score postoperative complications, while Kaplan−Meier methods and a Cox multivariable analysis were used to perform the survival analysis. Results: Of 163 patients, 78 (48%) underwent EPP and 85 (52%) eP/D. Induction chemotherapy was significantly administrated more often in the eP/D group (88% vs. 51%). Complete trimodality treatment including induction chemotherapy, radical surgery, and adjuvant radiotherapy was administered in 74% of the eP/D group versus 32% of the EPP group (p < 0.001). The postoperative morbidity rate was higher in the eP/D group (54%) compared to the EPP group (36%) (p = 0.02); no statistically significant differences were identified concerning major complications (EPP 43% vs. eP/D 24%, p = 0.08). No statistical differences were identified in 30-day mortality, 90-day mortality, median disease-free, and overall survival statistics between the two groups. The Cox multivariable analysis confirmed no induction chemotherapy (HR, 0.5; p = 0.002), RDW (HR, 1.08; p = 0.02), and the presence of pathological nodal disease (HR, 1.99; p = 0.001) as factors associated with worse survival in the entire series. Conclusions: Our data support that eP/D is a well-tolerated procedure allowing the implementation of a trimodality strategy (induction chemotherapy, surgery, and radiotherapy) in most MPM patients. When eP/D is offered in this setting, the oncological results are comparable to EPP. To obtain the best oncological results, the goal of surgical resection should be macroscopic complete resection (R0) in carefully selected patients (clinical N0).

Long-term outcomes after lung-sparing surgery for epithelial mesothelioma

Background

This observational study evaluates retrospectively the long-term outcomes after pleurectomy/decortication for pleural mesothelioma, with and without the resection/reconstruction of diaphragm and pericardium.

Methods

Data from 155 consecutive patients undergoing lung-sparing surgery for epithelial pleural mesothelioma were reviewed. Selection criteria for surgery were cT1-3, cN0-1, good performance status, age <80 years. Perioperative Pemetrexed-Platinum regimen was administered as induction in 101 cases (65.2%) and as adjuvant treatment in 54 cases (34.8%). Extended pleurectomy/decortication was performed in 87 cases (56.12%). In 68 patients (43.87%) standard pleurectomy/decortication was performed without resection/reconstruction of diaphragm and pericardium, when tumour infiltration was deemed absent after intraoperative frozen section. The log-rank test and Cox regression model were used to assess the factors affecting overall survival and recurrence free survival.

Results

Median follow-up was 20 months. The 2- and 5-year survival rate was 60.9% and 29.2% with a median survival of 34 months. An improved survival was observed when standard pleurectomy/decortication was carried out (P=0.007). A significant impact on survival was found comparing the TNM-stages (P=0.001), pT (P=0.002) and pN variables (P=0.001). Multivariate analysis identified the pN-status (P=0.003) and standard pleurectomy/decortication (P=0.017) as predictive for longer survival. The recurrence-free survival >12 months was strongly related to the overall survival (P<0.001). The macroscopic complete resection (P=0.001), TNM-stage (P=0.003) and pT-status (P=0.001) are related to relapse.

Conclusions

Within multimodal management of pleural mesothelioma, lung-sparing surgery is a valid option even with more conservative technique. A benefit for a longer survival was observed in the early stage of disease, with pN0 and when pleurectomy/decortication is carried out, preserving diaphragm and pericardium. Recurrence is not affected by the type of surgery, and a recurrence-free interval >12 months is predictive of an increased survival when the macroscopic complete resection is achieved.

Extended Pleurectomy/Decortication for Malignant Pleural Mesothelioma: Humanitas's Experience

BACKGROUND

We analysed a series of malignant pleural mesothelioma (MPM) patients who consecutively underwent extended Pleurectomy/Decortication (eP/D) in a centre with a high level of thoracic surgery experience (IRCCS Humanitas Research Hospital) to explore postoperative morbidity and mortality, pattern of recurrence and survival.

METHODS

A retrospective analysis was performed on MPM patients underwent eP/D in our centre from 2010 to 2021. All patients were identified from our departmental database. Postoperative complications were scored according to Clavien-Dindo criteria. Survival analysis was performed by the Kaplan-Meier methods and Cox multivariable analysis.

RESULTS

Eighty-five patients underwent extended pleurectomy decortication (eP/D) during study period. Macroscopical residual disease (R2) was reported in one case. A neoadjuvant chemotherapy regiment was administrated in 88% of the surgical cohort. A complete trimodality treatment including induction with platinum agents and pemetrexed, radical cytoreductive surgery and volumetric modulated arc therapy technology (VMAT) could be administered in 63 patients (74%). Postoperative morbidity rate was 54.11%, major complications (defined as Clavien-Dindo ≥ 3) were reported in 11 patients (12.9%). Thirty-day mortality and 90-day mortality were, respectively, 2.35% and 3.53%. Median disease-free and overall survival were, respectively, 13.7 and 25.5 months. The occurrence of major complications (Clavien-Dindo ≥ 3), operative time, pT3-T4, pathological node involvement (pN+) were prognostic factors associated with worse survival.

CONCLUSIONS

In our experience, eP/D is a well-tolerated procedure with acceptable mortality and morbidity, allowing for the administration of trimodality regimens in most patients. eP/D offered in a multimodality treatment setting have satisfactory long term oncological results. To obtain best oncological results the goal of surgery should be macroscopic complete resection in carefully selected patients (clinical N0).

Malignant pleural mesothelioma: Comparison of surgery-based trimodality therapy to medical therapy at two tertiary academic institutions

OBJECTIVES

Medical management based on palliative chemotherapy is currently the standard of care in malignant pleural mesothelioma (MPM). Median survival of 12-16 months has been reported with modern chemotherapy regimens with or without anti-angiogenic agents. Multimodality therapy incorporating cytoreductive surgery, systemic chemotherapy and radiotherapy has been offered for years to fit patients with early-stage disease, but its role remains debated. Our objective was to compare overall survival in patients offered multimodality therapy in a specialized clinic setting in London, UK to that of patients offered exclusively medical treatment at another academic institution in Quebec, Canada.

MATERIALS AND METHODS

We retrospectively compared the survival rates of 2 separate cohorts of patients treated consecutively: Cohort 1 (n = 106) received multimodality therapy including systemic chemotherapy, extended pleurectomy/decortication (P/D) and prophylactic radiotherapy in London (United Kingdom) between 2009 and 2016, while Cohort 2 (n = 98) received medical treatment at the Quebec Heart and Lung Institute (Canada) during the same period.

RESULTS

In Cohort 1, all patients but two completed trimodality therapy. In cohort 2, 51 % received palliative care only and 40 % received systemic chemotherapy. Median survival was 32 months vs 10 months in Cohort 1 and Cohort 2, respectively (hazard ratio with age, gender, pathology and TNM staging as covariates: 3.81; 95 % CI: 2.67-5.45; p < 0.0001). Similar results were obtained in sensitivity analyses, after excluding those who received best supportive care only and in a propensity score-matched analysis.

CONCLUSION

Aggressive therapy of MPM using cancer-directed surgery, systemic chemotherapy and prophylactic radiotherapy may provide a significant survival benefit in selected patients.

Japanese Current Status of Curative-Intent Surgery for Malignant Pleural Mesothelioma

BACKGROUND

Few reports about surgical outcomes in malignant pleural mesothelioma (MPM) were based on reliable nationwide databases. Here we analyzed the incidence, surgical outcome, and operative risk factors using Japanese nationwide database.

METHODS

Characteristics and perioperative data from 622 patients who underwent curative-intent surgery for MPM between January 2014 and December 2017 were recorded from National Clinical Database of Japan. We analyzed the incidence, surgical outcomes, and risk factors for surgical complications after two surgical procedures (extrapleural pneumonectomy, EPP; and pleurectomy/decortication, P/D).

RESULTS

During 4 years, EPP was performed in 279 patients and P/D in 343. EPP was more frequently performed in less-MPM-experienced institutions, while P/D was more frequently performed in well-MPM-experienced institutions (P < .001), especially in high-volume centers with more than 10 cases during this period. P/D was more frequently performed, especially in high-volume centers. The morbidity rates were 45.2% in EPP and 35.9% in P/D. Heart failure and pneumonia were most frequent in EPP, while prolonged air leakage was most frequent in P/D. Thirty-day- and in-hospital mortality rates were 1.1% and 3.2% (EPP) and 1.2% and 3.2% (P/D), respectively. Regression analyses revealed that higher age (>65 years) was associated with operative complications in EPP (odds ratio, OR: 3.56 [1.26-8.56]), whereas no risk factor was observed in P/D.

CONCLUSIONS

In Japanese nationwide annual database, P/D was more frequently performed, especially in high-volume centers. Morbidity was higher in EPP than P/D; however, the mortality rates were quite low in Japan regardless surgical procedures.

VATS Pleurectomy Decortication Is a Reasonable Alternative for Higher Risk Patients in the Management of Malignant Pleural Mesothelioma: An Analysis of Short-Term Outcomes

Simple Summary

Malignant pleural mesothelioma (MPM) is an aggressive malignancy that drastically affects a patient’s quality of life. Surgery typically entails radical resection with or without the removal of the underlying lung. In an era where minimally invasive surgery is sought after, MPM remains an anomaly. The purpose of this study is to assess the feasibility of minimally invasive surgery as an alternative to more radical surgery in MPM. We examined short-term outcomes between the radical approaches and minimally invasive surgery and minimally invasive surgery had improved outcomes. Minimally invasive surgery can be considered in patients with MPM.

Abstract

Surgery is a mainstay of treatment allowing for debulking of tumor and expansion of the lung for improvement in median survival and quality of life for patients with malignant pleural mesothelioma (MPM). Although optimal surgical technique remains open for debate—extrapleural pneumonectomy (EPP) vs. pleurectomy/decortication (P/D)—minimally invasive surgery (VATS-P/D) remains underutilized in the management of MPM. We examined whether VATS-P/D is a feasible alternative to EPP and P/D. We evaluated the New York Statewide Planning and Research Cooperative System (SPARCS) from 2007–2017 to assess the short-term complications of EPP vs. P/D, including a subanalysis of open P/D vs. VATS-P/D. There were 331 patients with open surgery; 269 with P/D and 62 with EPP. There were 384 patients with P/D; 269 were open and 115 VATS. Rates of any complication were similar between EPP and P/D patients, but EPP had significantly higher rates of cardiovascular complications. After adjusting for confounders, those with a VATS approach were less likely to have any complication, compared to an open approach and significantly less likely to have a pulmonary complication. VATS-P/D remains a viable alternative to radical surgery in MPM patients allowing for improved short-term outcomes.

ECLS for Life-Threatening Complications in Mesothelioma's Surgery: Is It Worthwhile?

Extracorporeal life support (ECLS) is an effective method for bridging patients to recovery in cases of respiratory and/or cardiac failure that are potentially reversible and unresponsive to conventional management. Nevertheless, there have been only few reports about the use of ECLS in oncological patients with complications due to their neoplasm or its treatment. We report the use of veno-arterial extracorporeal membrane oxygenation in three cases of severe perioperative complications following surgery for mesothelioma after induction chemotherapy at our Institution.

Landmark Trials in the Surgical Management of Mesothelioma

The treatment of mesothelioma has evolved slowly over the last 20 years. While surgery as a standalone treatment has fallen out of favor, the importance of multimodality treatment consisting of combinations of chemotherapy, radiotherapy, and surgery have become more common in operable, fit patients. In this review, we discuss trials in surgery, chemotherapy, and radiation that have shaped contemporary multimodality treatment of this difficult malignancy, and we touch on the new and emerging immunotherapeutic and targeted agents that may change the future treatment of this disease. We also review the multimodality treatment regimens, with particular attention to trimodality therapy and neoadjuvant hemithoracic radiation strategies.

Pleurectomy Decortication in the Treatment of Malignant Pleural Mesothelioma: Encouraging Results and Novel Prognostic Implications Based on Experience in 355 Consecutive Patients

OBJECTIVE

We report a series of 355 consecutive patients treated over 9 years in a single institution with intended PDC.

BACKGROUND

Surgery for MPM has shifted from extra-pleural pneumonectomy to PDC with the goal of MCR.

METHODS

Clinical and outcome data were reviewed. Kaplan-Meier estimators and log rank test were used to compare the overall survival, and logistic regression models were used.

RESULTS

MCR was achieved in 304. There were 223 males, median age was 69 and histology was epithelioid in 184. The 30 and 90-day mortality were 3.0% and 4.6%.Most complications were low grade. Prolonged air leak in 141, deep venous thrombosis in 64, Atrial fibrillation in 42, chylothorax in 24, Empyema in 23, pneumonia in 21, Hemothorax in 12 and pulmonary embolus in 8.Median/5-year survival were 20.7 months/17.9% in the intent-to-treat cohort and 23.2 months/21.2% in the MCR group. The survivals were best for patients with T1stage and epithelioid histology (69.8 months/54.1%). In a multivariable analysis, factors that were found to be associated with longer patient overall survival included epithelioid histology, T stage, quantitative clinical stage/tumor volume staging, adjuvant chemotherapy, intraoperative heated chemo, female sex, and length of stay shorter than 14 days.

CONCLUSIONS

PDC is feasible with low mortality and is associated with manageable complication rates. 5-year survival of patients undergoing PDC with MCR in multi-modality setting is approaching 25% depending on quantitative and clinical stage, sex and histological subtype and is better than PDC without- MCR.

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

BACKGROUND

The prognostic role of programmed cell death 1 ligand 1 (PD-L1) in malignant pleural mesothelioma (MPM) is incompletely understood. Our objectives were to evaluate the evidence for tumor PD-L1 as a prognostic biomarker in MPM through meta-analysis and to determine whether tumor PD-L1 expression is associated with survival in MPM patients undergoing macroscopic complete resection.

METHODS

Meta-analysis was performed to determine the association of PD-L1 with overall survival in MPM (n = 1655) from 14 studies containing overall survival and tumor PD-L1 expression. Univariable and multivariable analyses tested the relationship of tumor PD-L1 with overall survival and recurrence-free survival in an institutional cohort of MPM patients treated by macroscopic complete resection (n = 75). To validate the association of PD-L1 with overall survival, we utilized two independent MPM cohorts (n = 284).

RESULTS

Meta-analysis demonstrated that high tumor PD-L1 expression was associated with poor overall survival. Among 75 patients undergoing macroscopic complete resection, 49 tumors (65%) expressed PD-L1 (1% or more), and high PD-L1 (50% or greater) was more commonly expressed on nonepithelial (29%) compared with epithelial tumors (14%). High tumor PD-L1 expression was independently associated with poor overall survival (P < .001, hazard ratio 5.67) and recurrence-free survival (P = .003, hazard ratio 3.28). The association of PD-L1 overexpression with unfavorable survival was more significant in epithelial MPMs than nonepithelial MPMs. These findings were validated in RNA sequencing analyses in two independent cohorts. Exploratory transcriptome analysis revealed that MPM tumors with PD-L1 overexpression displayed coexpression of other immune regulatory molecules, programmed cell death 1 ligand 2 and T-cell immunoglobulin mucin receptor 3.

CONCLUSIONS

Tumor PD-L1 expression is a prognostic biomarker in patients undergoing surgical resection for MPM and may be useful in perioperative decision making.

Quantitation and predictors of short-term mortality following extrapleural pneumonectomy, pleurectomy/decortication, and nonoperative management for malignant pleural mesothelioma

Background

For malignant pleural mesothelioma (MPM), the benefit of resection, as well as the optimal surgical technique, remain controversial. In efforts to better refine patient selection, this retrospective observational cohort study queried the National Cancer Database in an effort to quantify and evaluate predictors of 30- and 90-day mortality between extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D), as well as nonoperative management.

Methods

After applying selection criteria, cumulative incidences of mortality by treatment paradigm were graphed for the unadjusted and propensity-matched populations, as well as for six a priori age-based intervals (≤60, 61–65, 66–70, 71–75, 76–80, and ≥81 years). The interaction between age and hazard ratio (HR) for mortality between treatment paradigms was also graphed. Cox multivariable analysis ascertained factors independently associated with 30- and 90-day mortality.

Results

Of 10,723 patients, 2,125 (19.8%) received resection (n=438 EPP, n=1,687 P/D) and 8,598 (80.2%) underwent nonoperative management. The unadjusted 30/90-day mortality for EPP, P/D, and all operated cases was 3.0%/8.0%, 5.4%/14.1%, and 4.9%/12.8%, respectively. There were no short-term mortality differences between EPP and P/D following propensity-matching, within each age interval, or between age subgroups on interaction testing (P>0.05 for all). Nonoperative patients had a crude 30- and 90-day mortality of 9.9% and 24.6%, respectively. Several variables were identified as predictors of short-term mortality, notably patient age (HR 1.022, P<0.001), Charlson-Deyo comorbidity index (HR 1.882, P<0.001), receipt of treatment at high-volume centers (HR 0.834, P=0.032) and induction chemotherapy (HR 1.735, P=0.025), among others. The patient (yearly) incremental increase in age conferred 2.0% (30 day) and 2.2% (90 day) increased risk of mortality (P<0.001).

Conclusions

Quantitative estimates of age-associated 30- and 90-day mortality of EPP and P/D should be considered when potentially operable patients are counseled regarding the risks and benefits of resection.

Updates in Staging and Management of Malignant Pleural Mesothelioma

While without treatment, malignant pleural mesothelioma (MPM) confers poor survival, cancer-directed surgery as part of multimodality treatment is associated with a 15% 5-year survival. Extrapleural pneumonectomy (EPP) and radical or extended pleurectomy/decortication (P/D) are the 2 types of resection performed in this context. Preoperative staging is critical to patient selection for surgery; P/D is recommended over EPP in most cases. Adjuvant therapy with intraoperative platforms, traditional chemotherapy, hemithoracic radiotherapy resection, and new immunotherapy agents are instrumental in achieving durable long-term results. We outline the latest understanding of disease staging and describe the current state of literature and practice.

Consensus Statement on Proton Therapy in Mesothelioma

PURPOSE

Radiation therapy for mesothelioma remains challenging, as normal tissue toxicity limits the amount of radiation that can be safely delivered to the pleural surfaces, especially radiation dose to the contralateral lung. The physical properties of proton therapy result in better sparing of normal tissues when treating the pleura, both in the postpneumonectomy setting and the lung-intact setting. Compared with photon radiation, there are dramatic reductions in dose to the contralateral lung, heart, liver, kidneys, and stomach. However, the tissue heterogeneity in the thorax, organ motion, and potential for changing anatomy during the treatment course all present challenges to optimal irradiation with protons.

METHODS

The clinical data underlying proton therapy in mesothelioma are reviewed here, including indications, advantages, and limitations.

RESULTS

The Particle Therapy Cooperative Group Thoracic Subcommittee task group provides specific guidelines for the use of proton therapy for mesothelioma.

CONCLUSIONS

This consensus report can be used to guide clinical practice, insurance approval, and future research.

Pleural mesothelioma: is the surgeon still there?

Malignant pleural mesothelioma (MPM) is a rare malignancy with some unique characteristics. Tumor biology is aggressive and prognosis is poor. Despite more knowledge on histology, tumor biology and staging, there is still a relevant discrepancy between clinical and pathologic staging resulting in difficult prediction of prognosis and treatment outcome, making treatment allocation more challenging than in most other malignancies. After years of nihilism in the late 80s, a period of activism started evaluating different treatment protocols combined with research driven mainly by academic centers; at the time, selection was based on histology and stage only. This period was important to gain knowledge about the disease. However, the interpretation of data was difficult since selection criteria and definitions varied substantially. Not surprisingly, until now there is no common agreement on best treatment even among specialists. Hence, a review of our current concepts is indicated and personalized treatment should become applicable in the future. Surgery was and still is an issue of debate. In principle, surgery is an effective approach as it allows macroscopic complete elimination of a tumor, which is relatively resistant to medical treatment. It helps to set the clock back and other therapies that have also just a limited effect can be applied sequentially before or after surgery. Furthermore, to date best long-term outcome is reported from surgical series in combination with other modalities. However, part of the community considers surgery associated with too high morbidity and mortality when balanced to the limited life expectancy. This criticism is understandable, since poor results after surgery are reported. The present article will review the indication for surgery and discuss the different procedures available for macroscopic complete resection-such as lung-preserving (extended) pleurectomy/decortication as well as extrapleural pneumonectomy to illustrate that 'The surgeon is still there!'

Extrapleural pneumonectomies for pleural mesothelioma

Introduction: Malignant pleural mesothelioma (MPM) is a fatal malignancy for which there is no definitive cure. The most effective multimodality treatment in prolonging survival is still matter of debate. Surgery remains one of the cornerstones in the multimodality therapy for MPM. Extra-pleural pneumonectomy and pleurectomy/decortication are the two main curative-intent procedures; however, the superiority of one technique over the other is still debated. This review aims to assess short- and long-term results of extrapleural pneumonectomy for MPM.Areas covered: This article focuses on the role of extrapleural pneumonectomy in MPM. A systematic review was performed by using electronic databases to identify studies that included patients treated by this procedure for MPM. Endpoints included overall survival, disease-free survival, recurrence rate, perioperative mortality, and morbidity.Expert commentary: This paper offers an overview of the results that are currently obtained in patients undergoing extrapleural pneumonectomy for MPM. The benefit of surgical treatments in MPM is still debated and its primary goal should be the achievement of a macroscopic complete resection. Several alternative multimodality protocols exist, with specific advantages and drawbacks; therefore, individualization of care for each patient is fundamental. The complexity of the surgical treatment mandates that patients be referred to specialized centers.

A 75 year old male with recurrent unilateral pleural effusion and positive ANA

This case report describes the clinical course and diagnostic challenges arising in a 75 year old man who initially presented with progressive shortness of breath. Imaging revealed a pleural effusion, which was recurrent following thoracentesis. While his initial workup suggested an autoimmune etiology, further diagnostic testing revealed a diagnosis of malignant pleural mesothelioma. Curiously, the patient had no known asbestos exposure, which is classically associated with acquired mesothelioma. There are a small number of similar cases with a possible overlap between positive autoimmune serologies and mesothelioma; however, the underlying pathophysiology remains elusive. It is the authors' goal to contribute this case to the few cases describing such overlap syndromes.

Prolonged post-recurrence survival following pleurectomy/decortication for malignant pleural mesothelioma

The present study analyzed surgical results in patients with malignant pleural mesothelioma (MPM) who underwent extrapleural pneumonectomy (EPP) or pleurectomy/decortication (P/D). Data for 44 patients who achieved macroscopic complete resection following neoadjuvant chemotherapy followed by EPP (n=29) or P/D (n=15) were reviewed. Patient demographics and oncological outcomes were compared between the EPP and P/D groups. The median overall (OS) and progression-free survival (PFS) times were 22 and 14 months, respectively. OS was significantly different between the EPP and P/D groups (median OS, 17 vs. 34 months; 5-year OS, 11 vs. 44%; P=0.019); no difference was noted in PFS (median PFS, 13 vs. 21 months; 5-year PFS, 11 vs. 17%; P=0.373). Univariate analysis demonstrated that epithelial histology (P=0.0003) and P/D (P=0.018) were significant favorable prognostic factors for OS. Using multivariate analysis, epithelial histology (P=0.001) remained the only significant factor. Post-recurrence survival (PRS) among all patients was significantly longer in the P/D group (median PRS, 3 vs. 20 months; 1.5-year PRS, 5 vs. 54%; P=0.003), even among patients with epithelial-type MPM (median PRS, 6 s vs. 20 months; 1.5-year PRS, 8 vs. 61%; P=0.012). Chemotherapy following recurrence (P=0.033) was significantly associated with superior PRS in multivariate analysis. Postoperative pulmonary function was significantly improved in the P/D group. In summary, P/D may be an alternative procedure to EPP for resectable MPM providing similar PFS and improved PRS.

A randomized phase II study of pleurectomy/decortication preceded or followed by (neo-)adjuvant chemotherapy in patients with early stage malignant pleural mesothelioma (EORTC 1205)

Radical multimodality treatment for malignant pleural mesothelioma (MPM) is controversial, with intense debate (but lack of data) about which surgical procedure to perform [extrapleural pneumonectomy (EPP) or pleurectomy/decortication (PD)], if any. In order to perform a randomized comparison, the most optimal sequence of surgery and chemotherapy should be determined. EORTC 1205 is a clinical trial randomizing between upfront surgery, followed by chemotherapy (cisplatin plus pemetrexed) and deferred surgery, following neoadjuvant chemotherapy in early stage (T1-3 N0-2 M0) MPM (irrespective of histological subtype). The surgical procedure performed is (extended) pleurectomy/decortication (e-PD), which is promoted as an alternative for EPP, but lacks standardization. Primary outcome parameter is successful completion of multimodality treatment; secondary outcome parameters are surgical quality parameters (in order to standardize the procedure), progression free survival (PFS) and overall survival (OS), treatment-failure free survival, operative morbidity and mortality, toxicity and safety.

Is There a Role for Cancer-Directed Surgery in Early-Stage Sarcomatoid or Biphasic Mesothelioma?

BACKGROUND

Benefits of surgical resection for early-stage nonepithelioid malignant pleural mesothelioma (MPM) have not been clearly elucidated. This study investigated whether cancer-directed surgery affects overall survival compared with nonsurgical therapies for T1-T2 N0 M0 sarcomatoid or biphasic MPM patients.

METHODS

Adult patients with clinical stage I or II MPM were identified in the National Cancer Database from 2004 to 2103. Patients who underwent cancer-directed surgery were matched by propensity score with patients who had received chemotherapy/radiotherapy or no treatments. Overall survival was compared using a Cox proportional hazard regression model.

RESULTS

From National Cancer Database queries, 878 patients with clinical stage I or II MPM with sarcomatoid (n = 524) or biphasic (n = 354) histology were identified. Overall median survival was 5.5 months for patients with sarcomatoid mesothelioma. The cancer-directed surgery improved overall survival compared with no operation (median survival, 7.56 months vs 4.21 months, respectively; p < 0.01). In the biphasic group, median overall survival was 12.2 months. Again, the cancer-directed surgery improved survival compared with no operation (15.8 months vs 9.3 months, p < 0.01). For both histologies, the cancer-directed surgery improved overall survival compared with those who underwent chemotherapy or radiotherapy, or both, without resection (p < 0.05). Perioperative mortality was 6.0% at 30 days and 21.4% at 90 days.

CONCLUSIONS

The cancer-directed surgery is associated with improved survival in early-stage MPM patients with nonepithelioid histology compared with those who did not undergo resection or chose medical therapy. Given the high perioperative mortality, a careful patient selection and multidisciplinary evaluation is recommended.

Surgical Options for Malignant Mesothelioma: A Single-Center Experience

Background

We investigated the surgical outcomes of patients who underwent therapeutic surgery for malignant pleural mesothelioma (MPM) at a single center.

Methods

A retrospective review of 21 patients who underwent therapeutic surgery for MPM from January 2001 to June 2015 was conducted to assess their outcomes. The patients’ characteristics and postoperative course, including complications, mortality, overall survival, and recurrence-free survival, were analyzed.

Results

Of the 21 patients who underwent therapeutic surgery, 15 (71.4%) underwent extrapleural pneumonectomy, 2 pleurectomy (9.5%), and 4 excision (19.1 %). The median age was 57 years (range, 32–79 years) and 15 were men (71.4%). The mean hospital stay was 16 days (range, 1–63 days). Median survival was 14.3 months. The survival rate was 54.2%, 35.6%, and 21.3% at 1, 3, and 5 years, respectively. In patients’ postoperative course, heart failure was a major complication, occurring in 3 patients (14.3%). The in-hospital mortality rate was 2 of 21 (9.5%) due to a case of severe pneumonia and a case of acute heart failure.

Conclusion

A fair 5-year survival rate of 21.3% was observed after surgical treatment. Heart failure was a major complication in our cohort. Various surgical methods can be utilized with MPM, each with its own benefits, taking into consideration the severity of the disease and the comorbidities of the patient. Patients with local recurrence may be candidates for surgical intervention, with possible satisfying results.

A Phase I Trial of Surgical Resection and Intraoperative Hyperthermic Cisplatin and Gemcitabine for Pleural Mesothelioma

INTRODUCTION

The primary objective of this single-institution phase I clinical trial was to establish the maximum tolerated dose of gemcitabine added to cisplatin and delivered as heated intraoperative chemotherapy after resection of malignant pleural mesothelioma.

METHODS

The extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D) treatment arms were based on investigators' assessment of patient fitness and potential for macroscopic complete resection. Previously established intracavitary dosing of cisplatin (range 175-225 mg/m²) with systemic cytoprotection was used in combination with escalating doses of gemcitabine, following a 3-plus-3 design from 100 mg/m² in 100-mg increments.

RESULTS

From 2007 to 2011, 141 patients were enrolled and 104 completed treatment. The median age of those completing treatment was 65 years (range 43-85 years), and 22 (21%) were female. In the EPP arm (n = 59), 31 patients (53%) had the epithelioid histologic type and the median radiographic tumor volume was 236 cm³ (range 16-4285 cm³). In the P/D arm (n = 41), 29 patients (71%) had the epithelioid histologic type and the median tumor volume was 79 cm³ (range 6-1107 cm³). The operative mortality rate was 2%, and 35 and 22 serious adverse events were encountered among 27 patients (46%) and 16 patients (39%) in the EPP and P/D arms, respectively. Dose-limiting toxicity (grade 3 leukopenia) was observed in two patients who were receiving 1100 mg/m² of gemcitabine, thus establishing the maximum tolerated dose at 1000 mg/m², in combination with 175 mg/m² of cisplatin. The median overall and recurrence-free survival times in treated patients were 20.3 and 10.7 months, respectively.

CONCLUSIONS

Combination cisplatin and gemcitabine heated intraoperative chemotherapy can be administered safely and feasibly in the context of complete surgical resection of malignant pleural mesothelioma by EPP or P/D.

Progress in the Management of Malignant Pleural Mesothelioma in 2017

Malignant pleural mesothelioma (MPM) is an uncommon, almost universally fatal, asbestos-induced malignancy. New and effective strategies for diagnosis, prognostication, and treatment are urgently needed. Herein we review the advances in MPM achieved in 2017. Whereas recent epidemiological data demonstrated that the incidence of MPM-related death continued to increase in United States between 2009 and 2015, new insight into the molecular pathogenesis and the immunological tumor microenvironment of MPM, for example, regarding the role of BRCA1 associated protein 1 and the expression programmed death receptor ligand 1, are highlighting new potential therapeutic strategies. Furthermore, there continues to be an ever-expanding number of clinical studies investigating systemic therapies for MPM. These trials are primarily focused on immunotherapy using immune checkpoint inhibitors alone or in combination with other immunotherapies and nonimmunotherapies. In addition, other promising targeted therapies, including pegylated adenosine deiminase (ADI-PEG20), which focuses on argininosuccinate synthase 1-deficient tumors, and tazemetostat, an enhancer of zeste 2 polycomb repressive complex 2 subunit inhibitor of BRCA1 associated protein 1 gene (BAP1)-deficient tumors, are currently being explored.

Determinants of malignant pleural mesothelioma survival and burden of disease in France: a national cohort analysis

This study was undertaken to determine the healthcare burden of malignant pleural mesothelioma (MPM) in France and to analyze its associations with socioeconomic deprivation, population density, and management outcomes. A national hospital database was used to extract incident MPM patients in years 2011 and 2012. Cox models were used to analyze 1- and 2-year survival according to sex, age, co-morbidities, management, population-density index, and social deprivation index. The analysis included 1,890 patients (76% men; age: 73.6 ± 10.0 years; 84% with significant co-morbidities; 57% living in urban zones; 53% in highly underprivileged areas). Only 1% underwent curative surgical procedure; 65% received at least one chemotherapy cycle, 72% of them with at least one pemetrexed and/or bevacizumab administration. One- and 2-year survival rates were 64% and 48%, respectively. Median survival was 14.9 (95% CI: 13.7-15.7) months. The mean cost per patient was 27,624 ± 17,263 euros (31% representing pemetrexed and bevacizumab costs). Multivariate analyses retained men, age >70 years, chronic renal failure, chronic respiratory failure, and never receiving pemetrexed as factors of poor prognosis. After adjusting the analysis to age, sex, and co-morbidities, living in rural/semi-rural area was associated with better 2-year survival (HR: 0.83 [95% CI: 0.73-0.94]; P < 0.01); social deprivation index was not significantly associated with survival. With approximately 1,000 new cases per year in France, MPMs represents a significant national health care burden. Co-morbidities, sex, age, and living place appear to be significant factors of prognosis.

Treatment of Malignant Pleural Mesothelioma: American Society of Clinical Oncology Clinical Practice Guideline

Purpose To provide evidence-based recommendations to practicing physicians and others on the management of malignant pleural mesothelioma. Methods ASCO convened an Expert Panel of medical oncology, thoracic surgery, radiation oncology, pulmonary, pathology, imaging, and advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 1990 through 2017. Outcomes of interest included survival, disease-free or recurrence-free survival, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations. Results The literature search identified 222 relevant studies to inform the evidence base for this guideline. Recommendations Evidence-based recommendations were developed for diagnosis, staging, chemotherapy, surgical cytoreduction, radiation therapy, and multimodality therapy in patients with malignant pleural mesothelioma. Additional information is available at www.asco.org/thoracic-cancer-guidelines and www.asco.org/guidelineswiki .

Surgery for malignant pleural mesothelioma: an international guidelines review

Currently there is no universally accepted surgical therapy for malignant pleural mesothelioma (MPM). The goal of surgery in this dismal disease is a macroscopic complete resection (MCR) and there are two types of intervention with a curative intent. At one side, there is the extrapleural pneumonectomy (EPP) which consists in an en-bloc resection of the lung, pleura, pericardium and diaphragm and at the other side, there is pleurectomy/decortication (P/D) a lung-sparing surgery. Initially, EPP was considered the only surgical option with a curative aim, but during the decades P/D have acquired a role of increasing importance in MPM therapy. Several randomized prospective trials are required to establish the best strategy in the treatment of pleural mesothelioma. Although which is the best surgical option remains unclear, the International Mesothelioma Interest Group (IMIG), recently have stated that the type of surgery depends on clinical factors and on individual surgical judgment and expertise. Moreover, according to the current evidence, the surgery should be performed in high-volume centres within multimodality protocols. The aim of this study is to examine the currently available international guidelines in the surgical diagnosis and treatment of MPM.

Consensus Report of the 2015 Weinman International Conference on Mesothelioma

On November 9 and 10, 2015, the International Conference on Mesothelioma in Populations Exposed to Naturally Occurring Asbestiform Fibers was held at the University of Hawaii Cancer Center in Honolulu, Hawaii. The meeting was cosponsored by the International Association for the Study of Lung Cancer, and the agenda was designed with significant input from staff at the U.S. National Cancer Institute and National Institute of Environmental Health Sciences. A multidisciplinary group of participants presented updates reflecting a range of disciplinary perspectives, including mineralogy, geology, epidemiology, toxicology, biochemistry, molecular biology, genetics, public health, and clinical oncology. The group identified knowledge gaps that are barriers to preventing and treating malignant mesothelioma (MM) and the required next steps to address barriers. This manuscript reports the group’s efforts and focus on strategies to limit risk to the population and reduce the incidence of MM. Four main topics were explored: genetic risk, environmental exposure, biomarkers, and clinical interventions. Genetics plays a critical role in MM when the disease occurs in carriers of germline BRCA1 associated protein 1 mutations. Moreover, it appears likely that, in addition to BRCA1 associated protein 1, other yet unknown genetic variants may also influence the individual risk for development of MM, especially after exposure to asbestos and related mineral fibers. MM is an almost entirely preventable malignancy as it is most often caused by exposure to commercial asbestos or mineral fibers with asbestos-like health effects, such as erionite. In the past in North America and in Europe, the most prominent source of exposure was related to occupation. Present regulations have reduced occupational exposure in these countries; however, some people continue to be exposed to previously installed asbestos in older construction and other settings. Moreover, an increasing number of people are being exposed in rural areas that contain noncommercial asbestos, erionite, and other mineral fibers in soil or rock (termed naturally occurring asbestos [NOA]) and are being developed. Public health authorities, scientists, residents, and other affected groups must work together in the areas where exposure to asbestos, including NOA, has been documented in the environment to mitigate or reduce this exposure. Although a blood biomarker validated to be effective for use in screening and identifying MM at an early stage in asbestos/ NOA-exposed populations is not currently available, novel biomarkers presented at the meeting, such as high mobility group box 1 and fibulin-3, are promising. There was general agreement that current treatment for MM, which is based on surgery and standard chemotherapy, has a modest effect on the overall survival (OS), which remains dismal. Additionally, although much needed novel therapeutic approaches for MM are being developed and explored in clinical trials, there is a critical need to invest in prevention research, in which there is a great opportunity to reduce the incidence and mortality from MM.

New Concepts in the Treatment of Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive and generally incurable cancer. Current anti-MPM chemotherapy-based treatments are only marginally effective, and long-term survival remains an unmet goal. Nonetheless, in selected cases, personalized surgery-based multimodality treatments (MMT) have been shown to significantly extend survival. The design of MMT and selection of patients are challenging, and optimal results require accurate presurgical diagnosis, staging, and risk stratification. Further, meticulous surgical techniques and advanced radiation protocols must be applied. We review key principles and evolving concepts in the care of MPM patients with a focus on the expanding role of MMT in MPM.

Pleurectomy and decortication

Pleurectomy and decortication (P/D) improve survival and quality of life in selected patients with malignant pleural mesothelioma. The operative procedure was not standardized until recently. The goal of the operation is to perform a macroscopic complete resection of the tumor. This often involves resection of the parietal and visceral pleura and invariably a partial or complete resection and prosthetic reconstruction of ipsilateral hemidiaphragm. We describe our operative planning and technique as well as outcomes of P/D reported in current literature.

A nuanced view of extrapleural pneumonectomy for malignant pleural mesothelioma

Multimodality treatment including macroscopic complete resection (MCR) is currently the most effective therapy for patients with malignant pleural mesothelioma (MPM). However, the allocation to one of the possible combinations has to be discussed individually since various factors influence the decision making process. In the past years, relevant new information about the disease and the outcome of different treatment modalities have been generated, which allows a more individual allocation to the best treatment. For many years extrapleural pneumonectomy (EPP)-the most aggressive procedure to achieve a MCR-was the first choice in combination with adjuvant or neo-adjuvant chemotherapy and radiation therapy for all patients except those with minimal disease. However, mortality and morbidity of an EPP and the fact, that even with the most radical procedure only MCR and not a complete resection can be achieved, led to shift towards pleurectomy/decortication in most of the centers. But also today, EPP is still a valuable option in selected cases and the entire treatment concept requires a nuanced view, which will be discussed in this review.

Extrapleural pneumonectomy (EPP) vs. pleurectomy decortication (P/D)

Surgical techniques for treatment of malignant pleural mesothelioma (MPM) have improved over the decades. The main surgical principle was accepted as macroscopic complete resection. This principle was achieved with extrapleural pneumonectomy (EPP) and extended pleurectomy/decortication (P/D). Mortality and morbidity are higher following EPP with supraventricular arrhythmias, pulmonary embolism, bronchopleural fistula and pulmonary failure being the most common, while prolonged air leak is frequent following P/D. Completion of multimodality treatment was also shown to be a prognostic factor. Many different neoadjuvant and adjuvant protocols were applied with limited effect on prognosis. While locoregional recurrence is more common following P/D, EPP patients typically recur in contralateral hemithorax and abdomen. Hemithoracic radiation following EPP was the only effective technique shown to decrease locoregional recurrence. However, neither surgical technique (EPP vs. P/D), nor types of multimodality treatment protocols were found to be prognostic in MPM. Epithelioid histology, metastasis to extrapleural lymph nodes and completion of multimodality treatment were prognostic in most of the series. In conclusion, based on the current evidence, the choice of a less morbid and mortal procedure (P/D) seems to be the logical choice in the treatment of MPM.

Extrapleural Pneumonectomy for Malignant Pleural Mesothelioma: A Novel Mini-Invasive Technique

We report a novel less-invasive extrapleural pneumonectomy for early-stage malignant pleural mesothelioma without rib spreading. Our approach is unique and differed from the previously reported cases, because we used one skin incision and two small intercostal incisions with videothoracoscopic viewing without rib spreading. The pleural dissection and approach to the hilum for pneumonectomy were performed through a 4- to 5-cm port incision in the sixth intercostal space. Another 4- to 5-cm port was made in the eight intercostal space through the same skin incision and was used for diaphragm resection and reconstruction. At the end of the surgery, the skin incision was enlarged to 8 cm; through which and the first port in the sixth intercostal space, the resected specimen was retrieved. Three cycles of adjuvant chemotherapy followed by radiation therapy were administered. Eleven-month follow-up showed no recurrence.

Improved Outcomes with Modern Lung-Sparing Trimodality Therapy in Patients with Malignant Pleural Mesothelioma

INTRODUCTION

Higher target conformity and better sparing of organs at risk with modern radiotherapy (RT) may result in higher tumor control and less toxicity. In this study, we compare our institutional multimodality therapy experience of adjuvant chemotherapy and hemithoracic intensity-modulated pleural RT (IMPRINT) with previously used adjuvant conventional RT (CONV) in patients with malignant pleural mesothelioma (MPM) treated with lung-sparing pleurectomy/decortication (P/D).

METHODS

We analyzed 209 patients who underwent P/D and adjuvant RT (131 who received CONV and 78 who received IMPRINT) for MPM between 1974 and 2015. The primary end point was overall survival (OS). The Kaplan-Meier method and Cox proportional hazards model were used to calculate OS; competing risks analysis was performed for local failure-free survival and progression-free survival. Univariate analysis and multivariate analysis were performed with relevant clinical and treatment factors.

RESULTS

The median age was 64 years, and 80% of the patients were male. Patients receiving IMPRINT had significantly higher rates of the epithelial histological type, advanced pathological stage, and chemotherapy treatment. OS was significantly higher after IMPRINT (median 20.2 versus 12.3 months, p = 0.001). Higher Karnofsky performance score, epithelioid histological type, macroscopically complete resection, and use of chemotherapy/IMPRINT were found to be significant factors for longer OS in multivariate analysis. No significant predictive factors were identified for local failure or progression. Grade 2 or higher esophagitis developed in fewer patients after IMPRINT than after CONV (23% versus 47%).

CONCLUSIONS

Trimodality therapy including adjuvant hemithoracic IMPRINT, chemotherapy, and P/D is associated with promising OS rates and decreased toxicity in patients with MPM. Dose constraints should be applied vigilantly to minimize serious adverse events.

Validation of a Gene Expression Test for Mesothelioma Prognosis in Formalin-Fixed Paraffin-Embedded Tissues

A molecular test performed using fresh-frozen tissue was proposed for use in the prognosis of patients with pleural mesothelioma. The accuracy of the test and its properties was assessed under Clinical Laboratory Improvement Amendments-approved guidelines using FFPE tissue from an independent multicenter patient cohort. Concordance studies were performed using matched frozen and FFPE mesothelioma samples. The prognostic value of the test was evaluated in an independent validation cohort of 73 mesothelioma patients who underwent surgical resection. FFPE-based classification demonstrated overall high concordance (83%) with the matched frozen specimens, on removal of cases with low confidence scores, showing sensitivity and specificity in predicting type B classification (poor outcome) of 43% and 98%, respectively. Concordance between research and clinical methods increased to 87% on removal of low confidence cases. Median survival times in the validation cohort were 18 and 7 months in type A and type B cases, respectively (P = 0.002). Multivariate classification adding pathologic staging information to the gene expression score resulted in significant stratification of risk groups. The median survival times were 52 and 14 months in the low-risk (class 1) and intermediate-risk (class 2) groups, respectively. The prognostic molecular test for mesothelioma can be performed on FFPE tissues to predict survival, and can provide an orthogonal tool, in combination with established pathologic parameters, for risk evaluation.