Pleurectomy/Decortication, Hyperthermic Pleural Lavage with Povidone-Iodine Followed by Adjuvant Chemotherapy in Patients with Malignant Pleural Mesothelioma

Pleurectomy and decortication are associated with better survival for bicavitary cytoreductive surgery for mesothelioma compared with extrapleural pneumonectomy

OBJECTIVES

Mesothelioma is a nearly uniformly fatal tumor. Multimodality therapy including cytoreductive surgery and chemotherapy is associated with long-term survival in some patients. Cytoreductive surgery for thoracic disease includes a lung-sparing operation called an "extended pleurectomy/decortication" or a lung-sacrificing surgery called an "extrapleural pneumonectomy." The benefit of cytoreductive surgery for bicavitary disease (chest and abdomen) is poorly understood. Our objective was to evaluate the long-term survivals for patients undergoing cytoreductive surgery for bicavitary disease and to determine whether any prognostic factors were associated with outcome.

METHODS

We reviewed our Institutional Review Board-approved, institutional, International Association for the Study of Lung Cancer Mesothelioma Staging Project database. Inclusion criteria were all patients who underwent cytoreductive surgery for bicavitary disease. Overall survival was calculated by Kaplan-Meier methodology. All International Association for the Study of Lung Cancer database elements were evaluated by univariable analysis.

RESULTS

From February 2014 to August 2021, 440 patients with mesothelioma were evaluated. Fourteen patients (3%) underwent cytoreductive surgery of both chest and abdomen as a planned 2-stage operation. Most patients (13/14; 93%) underwent chest surgery before abdomen surgery. For the entire cohort, the median overall survival was 33.6 months with a 5-year survival of 20%. Extended pleurectomy/decortication was associated with a better outcome compared with extrapleural pneumonectomy, with median overall survivals of 58.2 versus 13.5 months, respectively.

CONCLUSIONS

For a highly selected group of patients with bicavitary mesothelioma, long-term survival can be achieved with an aggressive, staged surgical approach. The patients who undergo extended pleurectomy/decortication with preservation of the lung appear to have more favorable outcomes compared with patients undergoing extrapleural pneumonectomy.

Postoperative empyema after pleurectomy decortication for malignant pleural mesothelioma

BACKGROUND

Postoperative empyema following pleurectomy decortication (PDC) for malignant pleural mesothelioma (MPM) is a serious complication that necessitates prolonged hospitalization. The aim of this study was to determine the incidence, risk factors and prognosis in patients who develop postoperative empyema following PDC.

METHODS

The background, type of PDC, neo-adjuvant treatment, date of empyema, pleural fluid cultures, post empyema treatment and prognosis from a series of consecutive 355 patients treated over 9 years at a single high-volume center were investigated. Fisher's exact test, Kaplan Meier estimators and log rank test were used to identify significant risk factors for postoperative empyema and compare the overall survival.

RESULTS

355 patients underwent PDC for MPM in a 9-year period. There were 263 males and median age at surgery was 69. Neoadjuvant therapy was given to 87 and 282 received intraoperative heated chemotherapy (IOHC). During the study 24 patients (6.8%) developed empyema. The length of stay (LOS) of patients who developed postoperative empyema was significantly longer. Median survival for patients who developed postoperative empyema was 11.7 months and 21.3 months for patients without empyema (HR-1.78, p=0.009). Postoperative empyema was associated with male sex, prolonged air leak and use of prosthetic mesh.

CONCLUSIONS

Postoperative empyema following PDC is associated with prolonged length of stay and higher mortality. The rates of this serious postoperative complication might decrease by developing better strategies to avoid prolonged air leak after PDC.

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.

Extended Pleurectomy and Decortication for Malignant Pleural Mesothelioma

Extended pleurectomy and decortication (ePD) is a difficult operation performed for the surgical resection of malignant pleural mesothelioma that can achieve a macroscopic complete resection with preservation of the lung. With lower perioperative mortality, similar long-term survival, and better tolerance in patients with lower performance status, ePD has become the preferred operation rather than extrapleural pneumonectomy despite lack of a direct comparison. As ePD has become more popular, international collaboration is underway to create surgical guidelines based on collection of operative data. These efforts will improve the safety and standardization of this operation.

Malignant Pleural Mesothelioma: State-of-the-Art on Current Therapies and Promises for the Future

Malignant pleural mesothelioma (MPM) is a rare, aggressive cancer of the pleural surface associated with asbestos exposure. The median survival of MPM patients is a mere 8-14 months, and there are few biomarkers and no cure available. It is hoped that, eventually, the incidence of MPM will drop and remain low and constant, given that most nations have banned the use of asbestos, but in the meantime, the incidence in Europe is still growing. The exact molecular mechanisms that explain the carcinogenicity of asbestos are not known. Standard therapeutic strategies for MPM include surgery, often coupled with chemotherapy and/or radiotherapy, in a small percentage of eligible patients and chemotherapy in tumors considered unresectable with or without adjuvant radiotherapy. In recent years, several new therapeutic avenues are being explored. These include angiogenesis inhibitors, synthetic lethal treatment, miRNA replacement, oncoviral therapies, and the fast-growing field of immunotherapy alone or in combination with chemotherapy. Of particular promise are the multiple options offered by immunotherapy: immune checkpoint inhibitors, tumor vaccines, and therapies taking advantage of tumor-specific antigens, such as specific therapeutic antibodies or advanced cell-based therapies exemplified by the CAR-T cells. This review comprehensively presents both old and new therapeutic options in MPM, focusing on the results of the numerous recent and on-going clinical trials in the field, including the latest data presented at international meetings (AACR, ASCO, and ESMO) this year, and concludes that more work has to be done in the framework of tailored therapies to identify reliable targets and novel biomarkers to impact MPM management.

Survival by Histologic Subtype of Malignant Pleural Mesothelioma and the Impact of Surgical Resection on Overall Survival

INTRODUCTION

For the 3 histologic subtypes of malignant pleural mesothelioma (MPM)-epithelioid, sarcomatoid, and biphasic-the magnitude of benefit with surgical management remains underdefined.

MATERIALS AND METHODS

The National Cancer Data Base was queried for newly diagnosed nonmetastatic MPM with known histology. Patients in each histologic group were dichotomized into those receiving gross macroscopic resection versus lack thereof/no surgery. Kaplan-Meier analysis evaluated overall survival (OS) between cohorts; multivariable Cox proportional hazards modeling assessed factors associated with OS. After propensity matching, survival was evaluated for each histologic subtype with and without surgery.

RESULTS

Overall, 4207 patients (68% epithelioid, 18% sarcomatoid, 13% biphasic) met the study criteria. Before propensity matching, patients with epithelioid disease experienced the highest median OS (14.4 months), followed by biphasic (9.5 months) and sarcomatoid (5.3 months) disease; this also persisted after propensity matching (P < .001). After propensity matching, surgery was associated with significantly improved OS for epithelioid (20.9 vs. 14.7 months, P < .001) and biphasic (14.5 vs. 8.8 months, P = .013) but not sarcomatoid (11.2 vs. 6.5 months, P = .140) disease. On multivariable analysis, factors predictive of poorer OS included advanced age, male gender, uninsured status, urban residence, treatment at community centers, and T4/N2 disease (all P < .05). Chemotherapy and surgery were independently associated with improved OS, as was histology (all P < .001).

CONCLUSION

This large investigation evaluated surgical practice patterns and survival by histology for MPM and found that histology independently affects survival. Gross macroscopic resection is associated with significantly increased survival in epithelioid and biphasic, but not sarcomatoid, disease. However, the decision to perform surgery should continue to be individualized in light of available randomized data.

Pleurectomy-decortication in malignant pleural mesothelioma: are different surgical techniques associated with different outcomes? Results from a multicentre study

OBJECTIVES

The potential benefit of surgery for malignant pleural mesothelioma (MPM), especially concerning pleurectomy/decortication (P/D), is unclear from the literature. The aim of this study was to evaluate the outcome after multimodality treatment of MPM involving different types of P/D and to analyse the prognostic factors.

METHODS

We reviewed 314 patients affected by MPM who were operated on in 11 Italian centres from 1 January 2007 to 11 October 2014.

RESULTS

The characteristics of the population were male/female ratio: 3.7/1, and median age at operation was 67.8 years. The epithelioid histotype was observed in 79.9% of patients; neoadjuvant chemotherapy was given to 57% of patients and Stage III disease was found following a pathological analysis in 62.3% of cases. A total of 162 (51.6%) patients underwent extended P/D (EP/D); 115 (36.6%) patients had P/D and 37 (11.8%) received only a partial pleurectomy. Adjuvant radiotherapy was delivered in 39.2% of patients. Median overall survival time after surgery was 23.0 [95% confidence interval (CI): 19.6-29.1] months. On multivariable (Cox) analysis, pathological Stage III-IV [ P  = 0.004, hazard ratio (HR):1.34; 95% CI: 1.09-1.64], EP/D and P/D ( P  = 0.006, HR for EP/D: 0.46; 95% CI: 0.29-0.74; HR for P/D: 0.52; 95% CI: 0.31-0.87), left-sided disease ( P  = 0.01, HR: 1.52; 95% CI: 1.09-2.12) and pathological status T4 ( P  = 0.0003, HR: 1.38; 95% CI: 1.14-1.66) were found to be independent significant predictors of overall survival.

CONCLUSIONS

Whether the P/D is extended or not, it shows similarly good outcomes in terms of early results and survival rate. In contrast, a partial pleurectomy, which leaves gross tumour behind, has no impact on survival.

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.

Malignant mesothelioma as a difficult interdisciplinary problem

The authors of the present report review the etiology and clinical symptoms of malignant pleural mesothelioma (MPM) as well as diagnostic techniques (both radiological and biomarkers) used for its detection. Subsequently, they present methods of multimodal treatment (surgery, chemotherapy, and radiotherapy) recommended by the International Mesothelioma Interest Group (IMIG). Finally, they discuss complications and long-term results associated with these methods of MPM treatment.

Effect of hyperthermic intrathoracic chemotherapy on the malignant pleural mesothelioma: a systematic review and meta-analysis

Surgery-based multimodality therapies have been used to control the malignant effusion and its recurrence in malignant pleural mesothelioma (MPM). Hyperthermic intrathoracic chemotherapy (HITHOC) has been used in the treatment of malignant pleural mesothelioma, but the results were controversial. The aim of the current study was, therefore, to conduct a systematic review and meta-analysis on the effect of HITHOC on MPM therapy. After thorough searching of online databases, total 21 articles were included into qualitative systematic review and 5 of them were used to conduct qualitative meta-analysis. It was found that most of HITHOC was used in combination of surgical resection including extrapleural pneumonectomy or pleurectomy/decortication. Patients who received HITHOC had significantly longer median survival length compared to the patients without HITHOC (Hedges's g = 0.384 ± 0.105, 95% CI: 0.178∼0.591, P < 0.001). In addition, HITHOC as palliative therapy was favored (Hedges's g = 0.591 ± 0.201, 95% CI: 0.196∼0.967, P < 0.001) in terms of recurrence free interval. The findings of the current study suggested that HITHOC is one of the safe and effective therapies in prolonging patients' median survival time and extending recurrence free interval.

Intraoperative adjuncts for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rapidly fatal disease. Multimodality surgically based therapies may extend survival in select patients, however, local relapse after resection is common. Novel intraoperative adjunctive therapies including heated intraoperative chemotherapy (HIOC), heated intraoperative povidone-iodine (PVP-I), and photodynamic therapy (PDT) target micrometastatic disease and aim to improve local control. This review details the most recent studies and trials of HIOC, heated intraoperative PVP-I, and PDT, this aims to provide an update on some of the most promising intraoperative adjuncts for patients with MPM.

The IASLC Mesothelioma Staging Project: Improving Staging of a Rare Disease Through International Participation

For nearly 40 years, there was no generally accepted staging system for malignant pleural mesothelioma. In 1994, members of the International Mesothelioma Interest Group, in collaboration with the International Association for the Study of Lung Cancer, proposed a TNM staging system based on analyses of outcomes in retrospective surgical series and small clinical trials. Subsequently accepted by the American Joint Commission on Cancer and the Union for International Cancer Control for the sixth editions of their staging manuals, this system has since been the international staging standard. However, it has significant limitations, particularly with respect to clinical staging and to the categories for lymph node staging. Here we provide an overview of the development of the International Association for the Study of Lung Cancer malignant pleural mesothelioma staging database, which was designed to address these limitations through the development of a large international data set. Analyses of this database, described in papers linked to this overview, are being used to inform revisions in the eighth editions of the American Joint Commission on Cancer and Union for International Cancer Control staging systems.

How does the timing of chemotherapy affect outcome following radical surgery for malignant pleural mesothelioma?

OBJECTIVES

There is little evidence regarding the use of chemotherapy as part of multimodality treatment of malignant pleural mesothelioma (MPM). We aimed to determine whether, in those patients fit for chemotherapy, a delay in this treatment affected survival.

MATERIALS AND METHODS

We analysed postoperative variables of 229 patients undergoing either extrapleural pneumonectomy (EPP) (81 patients) or extended pleurectomy-decortication (EPD) (197 patients) for MPM at a single centre. There was no standard protocol for additional chemotherapy and varied with referral centre. Outcome was compared between 4 chemotherapy strategies: true adjuvant therapy, neo-adjuvant therapy, therapy reserved until evidence of disease progression in those otherwise fit in the post-operative setting, and those unfit for chemotherapy.

RESULTS

There was no effect of the timing of chemotherapy on overall or progression free survival in patients fit enough for treatment (p=0.39 and p=0.33 respectively). However delaying chemotherapy until evidence of disease progression in patients with non-epithelioid disease had a detrimental effect on overall survival (OS), and on progression free survival (PFS) in lymph node positive patients (15.6 vs. 8.2 months p=0.001, and 14.9 vs. 6.0 months p=0.016). Further analysis of 169 patients receiving platinum/pemetrexed as first line treatment, showed similar results; there was no effect of the timing of chemotherapy on OS or PFS (p=0.80 and p=0.53 respectively) and an improved OS in patients with non-epithelioid disease, and improved PFS in those with lymph node metastases, if chemotherapy was given in the immediate adjuvant setting (p=0.001 and 0.038) when therapy was not delayed until disease progression.

CONCLUSION

Our results suggest that the timing of additional chemotherapy may be important in those with a poorer prognosis on the basis of cell type and nodal stage. In these patients additional postoperative chemotherapy should not be delayed.

The management of the diaphragm during radical surgery for malignant pleural mesothelioma

OBJECTIVES

Macroscopic complete resection with lung preservation is the objective of radical management of pleural mesothelioma (MPM). Total removal of visceral and parietal pleura (pleurectomy/decortication) almost invariably proceeds to an extended pleurectomy/decortication (EPD) to ensure macroscopic complete resection. We suspected this may not always be necessary.

METHODS

We reviewed 314 patients, 86.0% male, median age 62 years (range 14-81 years) undergoing radical surgery for MPM from 1999 to 2014, by either EPD or extrapleural pneumonectomy. The extent of diaphragmatic muscle involvement was recorded from postoperative pathology. Patients were divided into three groups: no involvement, non-transmural, transmural diaphragmatic invasion.

RESULTS

A total of 213 (68%) patients underwent EPD, 237 (75.5%) had epithelioid disease and 57.6% were node positive. There was no difference between the three groups in terms of age, cell type, laterality, neoadjuvant chemotherapy and operation. There was a higher degree of diaphragm involvement in females (P = 0.01) and in patients with positive lymph nodes (P = 0.01). No evidence of diaphragmatic involvement was found following pathological assessment of the resection specimen in 119 patients (37.9%). The incidence of abdominal disease progression was 23.9%. There was no correlation with degree of diaphragmatic invasion (ρ = 0.01 P = 0.88). Overall survival of those with abdominal progression was similar to those with progression elsewhere: 14.5 vs 13.0 months (P = 0.79), and with those with no progression (16.7 months, P = 0.189). There was no difference in survival when stratified by diaphragmatic involvement (P = 0.44).

CONCLUSIONS

In our cohort, there was no evidence of diaphragmatic invasion in over 30% of patients, and we have also failed to find evidence that peritoneal disease progression affects overall survival following radical management. It may therefore theoretically be unnecessary to resect the diaphragm in all cases, and a pleurectomy-decortication could suffice. However, there is an unknown risk of R2 resection which would prejudice survival, and as such we would advocate resecting the diaphragm in all cases to avoid an R2 resection.

New and emerging therapeutic options for malignant pleural mesothelioma: review of early clinical trials

Malignant pleural mesothelioma (MPM) is a rare tumor that is challenging to control. Despite some benefit from using the multimodality-approach (surgery, combination chemotherapy and radiation), survival remains poor. However, current research produced a list of potential therapies. Here, we summarize significant new preclinical and early clinical developments in treatment of MPM, which include mesothelin specific antibody and toxin therapies, interleukin-4 (IL-4) receptor toxins, dendritic cell vaccines, immune checkpoint inhibitors, and gene-based therapies. In addition, several local modalities such as photodynamic therapy, postoperative lavage using betadine, and cryotherapy for local recurrence, have also shown to be effective for local control of disease.

Extrapleural pneumonectomy plus rib resection for malignant pleural mesothelioma: a case report

We report a case of a 58-year-old Japanese man with epithelioid-type MPM, with a left chest wall protruding tumor, who underwent extrapleural pneumonectomy and chest wall resection. Postsurgical pathology showed that surgical margins were free of mesothelioma cells. Positron emission tomography taken 5 years after surgery showed no recurrence at any site, suggesting that long-term survival could be dependent on margin-free tumor resection or that specific MPM subgroups have lower malignant potential, leading to improved survival.

Extrapleural pneumonectomy or pleurectomy/decortication for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is associated with a very poor prognosis. Unlike other solid tumors, any type of planned surgery for MPM would be cytoreductive rather than radical. There are two types of surgery for MPM. Extrapleural pneumonectomy (EPP) involves en bloc resection of the lung, pleura, pericardium, and diaphragm. Pleurectomy/decortication (P/D) is a lung-sparing surgery that removes only parietal/visceral pleura. In comparison with EPP, P/D is theoretically less radical but is associated with less perioperative mortality/morbidity and less postoperative deterioration of cardiopulmonary function. It still remains unclear which surgical technique is superior in terms of the risk/benefit ratio. In this context, selection between EPP and P/D has been a matter to debate.

[Intraoperative chemotherapy after radical pleurectomy or extrapleural pneumonectomy]

Trimodality treatment including induction and/or adjuvant chemotherapy, surgical resection and in some cases radiotherapy offers a curative intention in selected patients with pleural malignancies (malignant pleural mesothelioma, thymoma with pleural spread). Nevertheless, locoregional tumor recurrence mainly limits the outcome and the quality of life. A few years ago an additional intraoperative chemotherapy perfusion was developed in order to improve local tumor control and prognosis after surgical resection in a multimodality treatment setting. Cytoreductive surgery with the purpose of a macroscopic complete resection could be achieved by radical pleurectomy or extrapleural pneumonectomy. The concept, techniques and perioperative management of this additional treatment option are presented along with a detailed review of the recent literature.

Surgical management of malignant pleural mesothelioma: impact of surgery on survival and quality of life-relation to chemotherapy, radiotherapy, and alternative therapies

Introduction. Malignant pleural mesothelioma (MPM) is an aggressive cancer arising from pleural mesothelium. Surgery aims to either cure the disease or control the symptoms. Two surgical procedures exist: extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D). In this systematic review we assess current evidence on safety and efficacy of surgery. Methods. Five electronic databases were reviewed from January 1990 to January 2013. Studies were selected according to a predefined protocol. Primary endpoint was overall survival. Secondary endpoints included quality of life, disease-free survival, disease recurrence, morbidity, and length of hospital stay. Results. Sixteen studies were included. Median survival ranged from 8.1 to 32 months for P/D and from 6.9 to 46.9 months for EPP. Perioperative mortality was 0%–9.8% and 3.2%–12.5%, respectively. Perioperative morbidity was 5.9%–55% for P/D and 10%–82.6% for EPP. Average length of stay was 7 days for P/D and 9 days for EPP. Conclusion. Current evidence cannot definitively answer which procedure (EPP or P/D) is more beneficial in terms of survival and operative risks. This systematic review suggests that surgery in the context of trimodality therapy offers acceptable perioperative outcomes and long-term survival. Centres specialising in MPM management have better results.

Surgery in mesothelioma--where do we go after MARS?

The role of surgery in the management of malignant pleural mesothelioma remains controversial. Surgical resection consists of different procedures for diagnostic or therapeutic reasons. The latter includes either an extrapleural pleuropneumonectomy (EPP) or lung-sparing operations like debulking of the parietal and visceral pleura by pleurectomy/decortication (P/D) or extended pleurectomy/decortication, in which further debulking of the diaphragm or pericardium is included. Because of the modest outcome of surgery as single-modality therapy, combinations of chemotherapy, surgery, and radiation therapy were initiated as a new treatment strategy to improve prognosis. The observations that patients treated with P/D had an equal to better outcome than those treated with EPP, and that EPP with perioperative chemotherapy was better than EPP alone, raises the issue whether performing a P/D with perioperative chemotherapy would result in a further improvement of outcome with a lower operative mortality than with EPP and perioperative chemotherapy. This is the rationale for the next European Organisation for Research and Treatment of Cancer trial exploring the feasibility of P/D with perioperative chemotherapy.

Malignant pleural mesothelioma: incidence, etiology, diagnosis, treatment, and occupational health

BACKGROUND

The incidence of malignant mesothelioma in Germany is about 20 cases per million persons per year. Its association with asbestos exposure, usually occupational, has been unequivocally demonstrated. Even though the industrial use of asbestos was forbidden many years ago, new cases of mesothelioma continue to appear because of the long latency of the disease (median, 50 years). Its diagnosis and treatment still present a major challenge for ambulatory and in-hospital care and will do so for years to come.

METHODS

This article is based on a selective review of the literature, along with data from the German Mesothelioma Register.

RESULTS

1397 people died of mesothelioma in Germany in 2010. A plateau in the incidence of the disease is predicted between 2015 and 2030. Most mesotheliomas arise from the pleura. The histological subtype and the Karnofsky score are the main prognostic factors. Only limited data are now available to guide treatment with a combination of the available methods (chemotherapy, surgery, radiotherapy). The prognosis is still poor, with a median survival time of only 12 months. Symptom control and the preservation of the patient's quality of life are the main aspects of care for patients with mesothelioma.

CONCLUSION

The incidence of mesothelioma is not expected to drop in the next few years. The available treatments are chemotherapy, surgery, and radiotherapy. Specialized treatment centers now increasingly provide multimodal therapy for treatment of mesothelioma.

Malignant pleural mesothelioma: update on treatment options with a focus on novel therapies

There is evidence that improved treatments of malignant pleural mesothelioma are increasing the quality and quantity of life for patients with mesothelioma. Multimodality treatment programs that combine maximal surgical cytoreduction with novel forms of radiation therapy and more effective chemotherapy combinations may offer significant increases in survival for certain subgroups of patients with mesothelioma. Lung-sparing surgery may allow improvements in pulmonary function after surgery-based multimodality therapy, and potential longer overall survival than that seen with extrapleural pneumonectomy. Experimental treatments provide hope for all patients with mesothelioma, and in the future may be combined with standard therapy in multimodality protocols.

Intraoperative hyperthermic chemotherapy perfusion for malignant pleural mesothelioma: an in vitro evaluation

OBJECTIVES

Hyperthermic chemotherapy perfusion has been used in the treatment of both pleural and peritoneal mesothelioma without an extensive basic science foundation. Clinical data are limited with no prospective randomized trials to support the use of this potentially toxic therapy. We sought to generate basic scientific support for this clinical practice and to define the optimal conditions for use in future clinical trials.

METHODS

Growth of a variety of in vitro established cell lines, including a hyperthermia-sensitive Chinese hamster ovary (CHO)-K1 cell line, a normal lung fibroblast line (MRC-5), a lung cancer line (A549), and 3 human mesothelioma cell lines (NCI-H28, NCI-H2052, and MSTO-211H), was assessed using a novel tetrazolium compound (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt [MTS]) and an electron coupling reagent (phenazine methosulfate), which measures the absorbance at 490 nm of a formazan product reduced from MTS by living cells (MTS metabolic assay), or a standard dilution clonogenic assay, which enumerates colony-forming units of more than 50 cells. Each cell line was plated into flasks and then exposed to varying combinations of chemotherapy agents and hyperthermia (37°C-45°C). The cells then were harvested and assessed in either assay. The role of chemotherapeutic agents currently most commonly used in clinical practice, including cisplatin, gemcitabine, and pemetrexed, was assessed with and without simultaneous heat exposure.

RESULTS

Conditions initially were explored using hyperthermia alone in CHO-K1, A549, and NCI-H28 cell lines using temperatures of 37°C, 42°C, and 45°C for 20, 40, and 60 minutes, respectively. This showed a reproducible dose-response curve in CHO-K1 cells with increasing temperature producing lower survival to only 1.5% of the control at 45°C for 60 minutes (P < .01). The A549 cells also showed a response but only at the highest temperature, and the NCI-H28 cells showed a more modest reduction to 65% at 45°C for 60 minutes (P < .01). When the 2 assays were directly compared, the MTS assay failed to detect differences between groups and therefore was discontinued from the remainder of these experiments. Next, hyperthermia was limited to the physiologic limit of 42°C, and the addition of chemotherapy was assessed. Doses were chosen on the basis of prior pharmacokinetic data from studies showing a maximum tissue/blood level of 200 ng/mL for cisplatin pleural instillation and were thought to more accurately reflect actual tumor levels. Cisplatin alone modestly reduced the clonogenic potential to 26%, 16.4%, and 13.6% at 42°C, respectively, for 60 minutes (P < .01); however, this was only a further reduction of 29.6%, 33.8%, and 34.2%, respectively, from the cisplatin alone control. Therefore, most of the reduction was attributable to chemotherapy and not hyperthermia. With combinations of cisplatin/gemcitabine and cisplatin/pemetrexed, the effect was larger, with reduction to 9.6%, 0%, and 0%, respectively (P < .01) (incremental reduction of 16.5%, 0%, and 0%, respectively, due to hyperthermia). Cisplatin/pemetrexed produced essentially identical results.

CONCLUSIONS

Intrapleural chemotherapy seems to be most effective when using 2 drug combinations. All mesothelioma cell lines showed no particular sensitivity to heat. The use of hyperthermia alone or with chemotherapy produces at best only a modest effect and does not necessarily support its current clinical use.