Factors influencing long-term survival in mesothelioma patients--results of the German mesothelioma register

The Western Australian Mesothelioma Registry: Analysis of 60 years of cases

BACKGROUND AND OBJECTIVE

Australia introduced a partial ban on asbestos consumption in 1984. There is continuing concern about exposure to asbestos in the built environment and non-occupational exposures. The aim of this study was to describe epidemiological trends of mesothelioma in Western Australia (WA) over the 60 years since the first case was recorded.

METHODS

Every case of mesothelioma notified to the WA Cancer Registry is reviewed by an expert panel. Data include demographic and clinical variables including principal mode of asbestos exposure and age at first exposure. Trends over time for survival, latency and pathological subtype of mesothelioma where analysed. Incidence rates for cases exposed during home renovation where calculated.

RESULTS

Two thousand seven hundred ninety-six cases of mesothelioma were identified with males comprising the majority (n = 2368, 84.7%). The median (IQR) age at diagnosis was 70 (62-78) years, and median latency of 47 (38-55) years. Pleural mesothelioma was recorded in 2620 (93.7%) cases with the epithelioid subtype most prevalent (n = 1730, 61.9%). Overall, median survival was 298 (128-585) days and latency 46 (37-54) years, both effectively doubling over the study period. Non-occupational exposures were proportionally higher in females (52.6%), compared with males (9.5%). Home renovation was the primary exposure in 227 (8.1%) cases, with number of cases and incidence rate ratio peaking in 2005/09 but subsequently decreasing.

CONCLUSION

The annual number of cases of mesothelioma in WA may have hit a plateau. The majority of females have non-occupational exposures and incidence rates from home renovation exposure may have peaked, suggesting the ban on asbestos has been effective.

Laying the Foundation for a Mesothelioma Patient Registry: Development of Data Collection Tools

Mesothelioma, a cancer of mesothelial cells that line the chest, lungs, heart, and abdomen, is a relatively rare disease. In the United States, approximately 3000 individuals are diagnosed with mesothelioma annually. The primary risk factor for mesothelioma is occupational asbestos exposure which can occur decades prior to disease development, though in approximately 20% of cases, known asbestos exposure is lacking. While several other countries have developed mesothelioma registries to collect key clinical and exposure data elements to allow better estimation of incidence, prevalence, and risk factors associated with disease development, no national mesothelioma registry exists in the U.S. Therefore, as part of a larger feasibility study, a patient exposure questionnaire and a clinical data collection tool were created using a series of key informant interviews. Findings suggest that risk factor and clinical data collection via an on-line questionnaire is feasible, but specific concerns related to confidentiality, in the context of employer responsibility for exposure in the unique U.S. legal environment, and timing of enrollment must be addressed. Lessons learned from piloting these tools will inform the design and implementation of a mesothelioma registry of national scope.

Analysis of the correlation between Zeste enhancer homolog 2 (EZH2) mRNA expression and the prognosis of mesothelioma patients and immune infiltration

Mesothelioma lies one of the most malignant tumors, in which the identification of the corresponding biomarkers is extremely critical. This study aims to investigate the prognostic value of enhancer homolog 2 (EZH2) mRNA expression in mesothelioma patients accompanied with its immune infiltration analysis. Gene expression, clinical information and enrichment analysis were obtained based on the Cancer Genome Atlas (TCGA), the immune infiltration analysis and bioinformatics analysis were performed. Clinical information and gene expression were obtained from 86 patients with mesothelioma based on TCGA database. Survival analysis, GSEA enrichment analysis, and immune infiltration analysis of EZH2 expression were carried out using R (version 3.6.3) (statistical analysis and visualization). The correlation of EZH2 expression with immune cell infiltration in mesothelioma was analyzed according to the TIMER database (Fig. https://cistrome.shinyapps.io/timer/). A univariate and multivariate analysis of general data obtained from the TCGA database was performed, involving age, gender, stage, pathological type, and whether they had received radiotherapy, the results indicated the association of high expression of EZH2 with poor prognosis in mesothelioma patients, with the worse prognosis in the High group (HR = 2.75, 95% CI 1.68–4.52, P < 0.010). Moreover, ROC curves showed that EZH2 expression predicted 1-year survival with an AUC of 0.740, 2-year survival with an AUC of 0.756, and 3-year survival with an AUC of 0.692, suggesting a robust predictive effect of EZH2 expression on prognosis. KEGG pathway analysis indicated five pathways showing the strongest positive correlation with EZH2 expression: cell cycle, DNA replication, Cell adhesion molecules cams, Primary immuno deficiency, Tsate transduction, and five pathways showing the strongest negative correlation with EZH2 expression: Glycolysis gluconeogenesis, Drug metabolism, cytochrome P450, retinol metabolism, fatty acid metabolism ribosome. We investigated the correlation between EZH2 expression and the level of immune infiltration in mesothelioma tissues. The results indicated that EZH2 expression played a critical role in immune infiltration, of which the high expression was correlated with the reduced number of NK cells, Mast cells, and Th17 cells. Moreover, mesothelioma patients with high EZH2 expression differ from those with low EZH2 expression in their tumor immune microenvironment. EZH2, as a new prognostic biomarker for mesothelioma, contributes to elucidating how changes in the immune environment promote the development of mesothelioma. Further analysis, EZH2 may serve as a biological test to predict the prognosis of mesothelioma.

Epidemiology and Clinical Aspects of Malignant Pleural Mesothelioma

Mesothelioma is a cancer predominantly of the pleural cavity. There is a clear association of exposure to asbestos with a dose dependent risk of mesothelioma. The incidence of mesothelioma in different countries reflect the historical patterns of commercial asbestos utilisation in the last century and predominant occupational exposures mean that mesothelioma is mostly seen in males. Modern imaging techniques and advances in immunohistochemical staining have contributed to an improved diagnosis of mesothelioma. There have also been recent advances in immune checkpoint inhibition, however, mesothelioma remains very challenging to manage, especially considering its limited response to conventional systemic anticancer therapy and that no cure exists. Palliative interventions and support remain paramount with a median survival of 9-12 months after diagnosis. The epidemiology and diagnosis of mesothelioma has been debated over previous decades, due to a number of factors, such as the long latent period following asbestos exposure and disease occurrence, the different potencies of the various forms of asbestos used commercially, the occurrence of mesothelioma in the peritoneal cavity and its heterogeneous pathological and cytological appearances. This review will describe the contemporary knowledge on the epidemiology of mesothelioma and provide an overview of the best clinical practice including diagnostic approaches and management.

The Association Between Pleural Fluid Exposure and Survival in Pleural Mesothelioma

BACKGROUND

Most patients with malignant pleural mesothelioma (MPM) seek treatment with malignant pleural effusion (MPE). In vitro evidence suggests that MPE may not be a simple bystander of malignancy, but rather potentially has biological properties that improve cancer cell survival and promote cancer progression. If this is the case, MPE management may need to shift from current symptomatic strategies to aggressive fluid removal to impact survival.

RESEARCH QUESTION

Is there an association between pleural fluid exposure and survival in MPM?

STUDY DESIGN AND METHODS

Data from 761 patients who received a diagnosis of MPM between 2008 and 2018 were collected from patient medical records in three UK pleural units. Data included factors previously identified as influencing prognosis in MPM. Medical imaging was reviewed for presence, size, and duration of pleural effusion. Time-dependent covariate analysis of pleural fluid exposure and survival (model included weight loss, serum albumin, hemoglobin, MPM subtype, performance status, chemotherapy, and age) and multivariate Cox regression analysis of pleurodesis and survival were conducted.

RESULTS

Median overall survival was 278 days (interquartile range, 127-505 days; 95% CI, 253-301 days). Pleural fluid exposure duration showed no association with survival (hazard ratio, 1.0; 95% CI, 1.0-1.0). Median survival was 473, 378, and 258 days with complete, partial, and no pleurodesis (P = .008).

INTERPRETATION

Pleurodesis success seems to be associated with improved survival; however, it is unclear whether duration of MPM exposure to pleural fluid is associated with survival within the limitations of this retrospective study. Future prospective studies are required to assess this potentially important mechanism.

Predicting survival in malignant pleural mesothelioma using routine clinical and laboratory characteristics

INTRODUCTION

The prognosis of malignant pleural mesothelioma (MPM) is poor, with a median survival of 8-12 months. The ability to predict prognosis in MPM would help clinicians to make informed decisions regarding treatment and identify appropriate research opportunities for patients. The aims of this study were to examine associations between clinical and pathological information gathered during routine care, and prognosis of patients with MPM, and to develop a 6-month mortality risk prediction model.

METHODS

A retrospective cohort study of patients diagnosed with MPM at Queen Alexandra Hospital, Portsmouth, UK between December 2009 and September 2013. Multivariate analysis was performed on routinely available histological, clinical and laboratory data to assess the association between different factors and 6-month survival, with significant associations used to create a model to predict the risk of death within 6 months of diagnosis with MPM.

RESULTS

100 patients were included in the analysis. Variables significantly associated with patient survival in multivariate analysis were age (HR 1.31, 95% CI 1.09 to 1.56), smoking status (current smoker HR 3.42, 95% CI 1.11 to 4.20), chest pain (HR 2.14, 95% CI 1.23 to 3.72), weight loss (HR 2.13, 95% CI 1.18 to 3.72), platelet count (HR 1.05, 95% CI 1.00 to 1.10), urea (HR 2.73, 95% CI 1.31 to 5.69) and adjusted calcium (HR 1.47, 95% CI 1.10 to 1.94). The resulting risk model had a c-statistic value of 0.76. A Hosmer-Lemeshow test confirmed good calibration of the model against the original dataset.

CONCLUSION

Risk of death at 6 months in patients with a confirmed diagnosis of MPM can be predicted using variables readily available in clinical practice. The risk prediction model we have developed may be used to influence treatment decisions in patients with MPM. Further validation of the model requires evaluation of its performance on a separate dataset.

Gender Differences in Outcomes of Patients With Mesothelioma

BACKGROUND

Mesothelioma is a rare and deadly form of cancer, linked to asbestos exposure. Although the United Kingdom has banned asbestos, the incidence rate remains high. Previous research has indicated that female individuals have better survival than male individuals, but this has never been examined in the United Kingdom.

MATERIALS AND METHODS

Pleural mesothelioma cases from 2005 to 2014 were extracted from the United Kingdom Lung Cancer Dataset. Multivariable logistic regression was used to assess the clinical and demographic factors associated with gender. A multivariable Cox proportional hazards model and propensity matching methods were used to assess gender differences in overall survival while accounting for potential confounders.

RESULTS

There were 8479 (87.8%) male and 1765 (17.2%) female individuals included in the analysis. Female individuals were significantly younger, with more epithelial histology than male individuals. Female individuals had significantly better overall survival (adjusted hazard ratio, 0.85, 95% confidence interval, 0.81-0.90). Results remained similar when stratifying by age and performance status, and when limiting to patients with epithelial histology.

CONCLUSIONS

The study increases knowledge about gender differences in mesothelioma survival and is the first to directly examine this in the United Kingdom. It further disentangles the effects of age, histology, and health status. Increased estrogen may improve survival and could provide a potential target for future therapies.

Survival prediction in mesothelioma using a scalable Lasso regression model: instructions for use and initial performance using clinical predictors

Introduction

Accurate prognostication is difficult in malignant pleural mesothelioma (MPM). We developed a set of robust computational models to quantify the prognostic value of routinely available clinical data, which form the basis of published MPM prognostic models.

Methods

Data regarding 269 patients with MPM were allocated to balanced training (n=169) and validation sets (n=100). Prognostic signatures (minimal length best performing multivariate trained models) were generated by least absolute shrinkage and selection operator regression for overall survival (OS), OS <6 months and OS <12 months. OS prediction was quantified using Somers D_XY statistic, which varies from 0 to 1, with increasing concordance between observed and predicted outcomes. 6-month survival and 12-month survival were described by area under the curve (AUC) scores.

Results

Median OS was 270 (IQR 140-450) days. The primary OS model assigned high weights to four predictors: age, performance status, white cell count and serum albumin, and after cross-validation performed significantly better than would be expected by chance (mean D_XY0.332 (±0.019)). However, validation set D_XY was only 0.221 (0.0935-0.346), equating to a 22% improvement in survival prediction than would be expected by chance. The 6-month and 12-month OS signatures included the same four predictors, in addition to epithelioid histology plus platelets and epithelioid histology plus C-reactive protein (mean AUC 0.758 (±0.022) and 0.737 (±0.012), respectively). The <6-month OS model demonstrated 74% sensitivity and 68% specificity. The <12-month OS model demonstrated 63% sensitivity and 79% specificity. Model content and performance were generally comparable with previous studies.

Conclusions

The prognostic value of the basic clinical information contained in these, and previously published models, is fundamentally of limited value in accurately predicting MPM prognosis. The methods described are suitable for expansion using emerging predictors, including tumour genomics and volumetric staging.

The revised staging system for malignant pleural mesothelioma based on surveillance, epidemiology, and end results database

BACKGROUND

Several staging systems for MPM have been introduced. However, none of them provide perfect survival stratification among heterogeneous patients. The aim of this population-based cohort study was to propose adjustments to current staging system for malignant pleural mesothelioma (MPM).

METHODS

We retrieved MPM data from Surveillance, Epidemiology, and End Results database (1973-2014). Kaplan-Meier method was derived to examine the prognostic effects of tumor, lymph node, metastasis and histology features. Proportional hazards models guided adjustments to stage groupings. The accuracy of staging systems at predicting survival was evaluated by concordance index and bootstrap resampling.

RESULTS

A total of 1110 MPM cases were extracted from SEER. T stage failed to demonstrate survival difference between adjacent categories with the exception of T3 versus T4 (P < 0.001). Patients in M0 had better prognosis than those in M1 (P < 0.001). Exploratory analyses suggested important survival difference for single-versus multiple-site M1 cases (P < 0.001), but not for different metastatic sites (P = 0.286). Histology subtype was a significant prognostic indicator (P < 0.001). Regrouping of TNM and histology combinations resulted in the best concordance index (0.683), compared with UICC 2010 (0.578) and IASLC 2016 (0.585) staging systems. The revised staging system also improved patients distribution (IA:33.8%, IB:17.0%, II: 20.7%, IIIA:10.6%, IIIB: 6.8%, IV:11.1%). Log-rank analyses and calibration plots both demonstrated the new stage achieved optimal survival prediction and discrimination.

CONCLUSION

The revised staging system improved patients distribution and survival stratification for MPM.

Clinical staging of malignant pleural mesothelioma: current perspectives

Malignant pleural mesothelioma (MPM) is a disease with limited therapeutic options, the management of which is still controversial. Diagnosis is usually made by thoracoscopy, which allows multiple biopsies with histological subtyping and is indicated for staging purposes in surgical candidates. The recommended and recently updated classification for clinical use is the TNM staging system established by the International Mesothelioma Interest Group and the International Association for the Study of Lung Cancer, which is based mainly on surgical and pathological variables, as well as on cross-sectional imaging. Contrast-enhanced computed tomography is the primary imaging procedure. Currently, the most used measurement system for MPM is the modified Response Evaluation Criteria in Solid Tumors (RECIST) method, which is based on unidimensional measurements of tumor thickness perpendicular to the chest wall or mediastinum. Magnetic resonance imaging and functional imaging with ¹⁸F-fluoro-2-deoxy-D-glucose positron-emission tomography can provide additional staging information in selected cases, although the usefulness of this method is limited in patients undergoing pleurodesis. Molecular reclassification of MPM and gene expression or miRNA prognostic models have the potential to improve prognostication and patient selection for a proper treatment algorithm; however, they await prospective validation to be introduced in clinical practice.

Epidemiology of mesothelioma of the pericardium and tunica vaginalis testis

PURPOSE

Malignant mesothelioma most commonly arises in the pleura and peritoneum but also occurs rarely at other anatomical sites with mesothelial tissue, namely, the pericardium and tunica vaginalis testis (TVT). This review provides a better understanding of the epidemiology of mesothelioma of these extrapleural sites.

METHODS

We conducted a systematic review of the epidemiologic and clinical literature on pericardial mesothelioma and mesothelioma of the TVT. We also analyzed U.S. Surveillance, Epidemiology, and End Results cancer registry data to describe incidence patterns of these malignancies.

RESULTS

An etiologic role of asbestos exposure has been hypothesized for pericardial and TVT mesotheliomas, but no analytical case-control epidemiologic studies exist to test this relationship. A substantial proportion of cases with these malignancies report no known asbestos exposure. In large occupational cohorts with heavy asbestos exposures, no cases of pericardial or TVT mesothelioma have been reported. Trends in the incidence of these malignancies do not match those of pleural mesothelioma, which correspond to historical trends of commercial asbestos use. A male preponderance of pericardial mesothelioma is not evident.

CONCLUSIONS

In the absence of analytic epidemiologic studies, the etiologic role of environmental risk factors for mesothelioma of the pericardium and TVT remains elusive.

Mesothelioma from asbestos exposures: Epidemiologic patterns and impact in the United States

Mesothelioma, a rare tumor, is highly correlated with asbestos exposure. Mesothelioma, similar to all asbestos-related diseases, is dose/intensity dependent to some degree, and studies showed the risk of mesothelioma rises with cumulative exposures. Multiple processes occur in an individual before mesothelioma occurs. The impact of mesothelioma in the United States has been continuous over the last half century, claiming between 2,000 and 3,000 lives each year. Mesothelioma is a preventable tumor that is more frequently reported as associated with asbestos exposure among men than women. However, the rate of asbestos-associated mesothelioma is on the rise among women due to better investigation into their histories of asbestos exposure. It is of interest that investigators detected asbestos-associated cases of mesothelioma in women from nonoccupational sources-that is, bystander, incidental, or take-home exposures. It is postulated that asbestos-associated mesotheliomas, in both men and women, are likely underreported. However, with the implementation of the most recent ICD-10 coding system, the correlation of mesothelioma with asbestos exposure is expected to rise to approximately 80% in the United States. This study examined the demographic and etiological nature of asbestos-related mesothelioma.

Sarcomatoid mesothelioma: future advances in diagnosis, biomolecular assessment, and therapeutic options in a poor-outcome disease

Malignant pleural mesothelioma (MPM) is the most frequent pleural neoplasm, with asbestos exposure as one of the recognized carcinogen agents, causative in 80% of cases. The prognosis is poor; median survival of untreated cases is 6-9 months, with fewer than 5% of patients surviving 5 years. Sarcomatoid mesothelioma (SM) represents the subtype with the worst outcome and median survival ranging from 3.5 to 8 months. In the last few years, an accurate differentiation between the subtypes of MPM has become a crucial issue, due to differences in chemosensitivity and clinical outcome, and several studies have evaluated different immunohistochemical markers to better define the diagnosis. The different and worse outcome of patients with SM and, in general, nonepithelioid subtypes makes it intriguing to select these cases to better study the biomolecular profile in order to find factors linked to prognosis and/or predictive of therapeutic response. Considering recent studies on miRNA and genetic mapping, further investigation of this rare subtype might represent a field for basic and clinical-translational research providing for more tailored therapies.

The effect of chemotherapy on health-related quality of life in mesothelioma: results from the SWAMP trial

Background:

The effect of chemotherapy on health-related quality of life (HRQoL) in malignant pleural mesothelioma (MPM) is poorly understood. Patient-individualised prognostication and prediction of treatment response from chemotherapy is useful but little evidence exists to guide practice.

Method:

Consecutive patients with MPM who were fit for first-line chemotherapy with pemetrexed and cisplatin\carboplatin were recruited and followed up for a minimum of 12 months. This study focussed on the HRQoL outcomes of these patients using the EQ-5D, EORTC QLQ-C30 and LC13.

Results:

Seventy-three patients were recruited of which 58 received chemotherapy and 15 opted for best supportive care (BSC). Compliance with HRQoL questionnaires was 98% at baseline. The chemotherapy group maintained HRQoL compared with the BSC group whose overall HRQoL fell (P=0.006) with worsening dyspnoea and pain. The impact of chemotherapy was irrespective of histological subtype although those with non-epithelioid disease had worse HRQoL at later time points (P=0.012). Additionally, those with a falling mesothelin or improvement on modified-RECIST CT at early follow-up had a better HRQoL at 16 weeks.

Conclusions:

HRQoL was maintained following chemotherapy compared with a self-selected BSC group. Once chemotherapy is initiated, a falling mesothelin or improved RECIST CT findings infer a quality-of-life advantage.

Supplementary prognostic variables for pleural mesothelioma: a report from the IASLC staging committee

INTRODUCTION

The staging system for malignant pleural mesothelioma is controversial. To revise this system, the International Association for the Study of Lung Cancer Staging Committee developed an international database. This report analyzes prognostic variables in a surgical population, which are supplementary to previously published CORE variables (stage, histology, sex, age, and type of procedure).

METHODS

Supplementary prognostic variables were studied in three scenarios: (1) all data available, that is, patient pathologically staged and other CORE variables available (2) only clinical staging available along with CORE variables, and (3) only age, sex, histology, and laboratory parameters are known. Survival was analyzed by Kaplan-Meier, prognostic factors by log rank and stepwise Cox regression modeling after elimination of nonsignificant variables. p value less than 0.05 was significant.

RESULTS

A total of 2141 patients with best tumor, node, metastasis (TNM) stages (pathologic with/without clinical staging) had nonmissing age, sex, histology, and type of surgical procedure. Three prognostic models were defined. Scenario A (all parameters): best pathologic stage, histology, sex, age, type of surgery, adjuvant treatment, white blood cell count (WBC) (≥15.5 or not), and platelets (≥400 k or not) (n = 550). Scenario B (no surgical staging): clinical stage, histology, sex, age, type of surgery, adjuvant treatment, WBC, hemoglobin (<14.6 or not), and platelets (n = 627). Scenario C (limited data): histology, sex, age, WBC, hemoglobin, and platelets (n = 906).

CONCLUSION

Refinement of these models could define not only the appropriate patient preoperatively for best outcomes after cytoreductive surgery but also stratify surgically treated patients after clinical and pathologic staging who do or do not receive adjuvant therapy.

Wnt7A is a putative prognostic and chemosensitivity marker in human malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive tumor that has a poor prognosis, limited treatment options, and a worldwide incidence that is expected to increase in the next decade. We evaluated Wnt7A expression in 50 surgically resected tumor specimens using quantitative PCR. The expression values, were assessed by clinicopathological factors and K-M and Cox's regression with OS. The mean level of Wnt7A expression had a significant correlation with International Mesothelioma Interest Group (IMIG) stage (P<0.034), gender, smoking history and ethnicity, respectively (P=0.020, P=0.014, P=0.039). In the univariate analysis, low Wnt7A expression was a significant negative factor for overall survival (P=0.043, HR=2.30). However, multivariate Cox's regression revealed no significant factors for overall survival (low Wnt7A: P=0.051, HR=2.283; non-epithelioid subtype: P=0.050, HR=2.898). In patients with epithelioid tumors, those with low Wnt7A expression had significantly worse prognosis (P=0.019, HR=2.98). In patients with epithelioid tumors, females had significantly better prognosis than males (P=0.035). In patients who did not have neoadjuvant chemotherapy, prognosis was significantly more favorable for patients with high Wnt7A expression than for those with low Wnt7A expression (P=0.031). Among the patients with low Wnt7A-expressing tumors, those who received neoadjuvant chemotherapy had better prognosis than those who did not (P=0.024). The results of our study suggest that Wnt7A expression is a putative prognostic factor and a predictor of chemosensitivity.

Malignant pleural mesothelioma incidence and survival in the Republic of Ireland 1994-2009

OBJECTIVE

Malignant pleural mesothelioma (MPM) is a rare malignancy associated with exposure to asbestos. The protracted latent period of MPM means that its incidence has continued to rise across Europe after the introduction of restrictions on asbestos use. In order to obtain a clearer indication of trends in the Republic of Ireland (ROI), incidence and survival were assessed based on all MPM cases reported since the establishment of the National Cancer Registry of Ireland (NCR).

METHODS

NCR recorded 337 MPM diagnoses in the ROI during 1994-2009. Survival was assessed for all cases diagnosed with adequate follow-up (n=330). Crude and European age-standardized incidence rates were calculated for all cases and for 4-year periods. A Cox model of observed (all-cause) survival was used to generate hazard ratios for the effect of: gender; age at diagnosis; diagnosis cohort; region of residence; histological type; and tumour stage. Single P-values for the variables indicated were calculated using either a stratified log-rank test or stratified trend test.

RESULTS

Over the study period the age-standardized MPM incidence in the ROI rose from 4.98cases per million (cpm) to 7.24cpm. The 1-year survival rate for all MPM cases was 29.6% (CI 24.7-34.6%). Excess mortality risk was associated with age at diagnosis (75-89 yrs vs. 55-64 yrs, HR 1.88, 95% CI 1.35-2.63, P<0.001) and tumour stage (III vs. I HR 1.57, 95% CI 1.00-2.48, P<0.05; IV vs. I HR 1.55, 95% CI 1.08-2.21, P<0.05). Age showed a significant survival trend (P<0.001) but tumour stage did not (P=0.150). There was significant heterogeneity between the survival of patients resident in different regions (P=0.027).

CONCLUSION

MPM incidence and mortality continued to rise in the ROI after the restrictions on asbestos use and the predictors of survival detected in this study are broadly consistent with those identified for other countries.

[Regional treatment of malignant pleural mesothelioma: results from the tumor centre Regensburg]

INTRODUCTION

Malignant pleural mesothelioma (MPM) is an aggressive, malignant tumor of the pleural surface and is strongly associated with asbestos exposure. Incidence of MPM will reach its peak over the coming years. Most patients present with advanced tumor stages and therefore surgical options are limited.

PATIENTS AND METHODS

Retrospective analysis of all patients with MPM reported to the tumor centre Regensburg between January 1998 and August 2011.

RESULTS

A total of 118 patients (85 % male) with cytologically or histologically confirmed MPM were reported. The mean age at diagnosis was 67 years (range 45-84 years) and 65 % of patients had a history of asbestos exposure. The incidence of MPM at the tumor centre Regensburg was 0.8/100,000 inhabitants with obvious regional differences depending on asbestos exposure. Staging was completed in 81 patients (67 %): stage I 9 %, stage II 22 %, stage III 23 % and stage IV 46 %. Of the patients 87 (74 %) underwent at least one surgical procedure: diagnostic thoracoscopy with biopsy (n = 37, 43 %), debulking surgery or talcum pleurodesis (n = 33, 38 %) and potentially curative resection (n = 17, 19 %). After a mean follow-up of 20 months the overall median survival was 14 months (1 year survival rate 62 %, 3 year survival rate 15 %). Patients had a significantly better median survival of 18 months after curative resection.

CONCLUSIONS

The distribution of MPM varies according to regional and industrial asbestos exposure. Screening and diagnostics should concentrate on locations with higher incidence of MPM to facilitate surgical therapy in a multimodal treatment regime.

The ticking time-bomb of asbestos: its insidious role in the development of malignant mesothelioma

The relationship between asbestos exposure and malignant mesothelioma (MM) has been well established. Despite bans on asbestos use in an increasing number of nations, the prolonged latency from exposure to diagnosis, and the ongoing presence and use of these dangerous fibres, have led to the increasing prevalence of this deadly disease worldwide. Whilst occupational contact has been implicated in the bulk of diagnosed cases over the past 50 years, a significant proportion of disease has been linked to para-occupational, domestic and environmental exposure. In this review, we will provide an update on the impact of historical and ongoing asbestos contact in both occupational and non-occupational settings. Furthermore, we will address the unresolved controversies surrounding the use of chrysotile asbestos, the effect of gender and genetics on development of this disease, childhood mesothelioma and co-aetiological factors including SV40 exposure.

Factors that impact susceptibility to fiber-induced health effects

Asbestos and related fibers are associated with a number of adverse health effects, including malignant mesothelioma (MM), an aggressive cancer that generally develops in the surface serosal cells of the pleural, pericardial, and peritoneal cavities. Although approximately 80% of individuals with MM are exposed to asbestos, fewer than 5% of asbestos workers develop MM. In addition to asbestos, other mineralogical, environmental, genetic, and possibly viral factors might contribute to MM susceptibility. Given this complex etiology of MM, understanding susceptibility to MM needs to be a priority for investigators in order to reduce exposure of those most at risk to known environmental carcinogens. In this review, the current body of literature related to fiber-associated disease susceptibility including age, sex, nutrition, genetics, asbestos, and other mineral exposure is addressed with a focus on MM, and critical areas for further study are recommended.

A novel prognostic model for malignant mesothelioma incorporating quantitative FDG-PET imaging with clinical parameters

PURPOSE

Existing prognostic systems for malignant pleural mesothelioma do not incorporate imaging information. We aimed to identify the contribution of quantitative fluorodeoxyglucose positron emission tomography (FDG-PET) analysis to other prognostic variables in this disease.

EXPERIMENTAL DESIGN

Patients with malignant pleural mesothelioma underwent helical thoracoabdominal computed tomography and FDG-PET scans at baseline. Patients were treated as clinically indicated and followed for survival. FDG-PET variables derived included total glycolytic volume, a composite of tumor volume and glycolytic activity.

RESULTS

Ninety-three patients were accrued from 2003 to 2006. Of 89 eligible assessable patients, 28 had undergone pleurodesis before enrolment. Seventeen patients remained alive at analysis; median survival is 15.4 months. On univariate analysis, significant prognostic factors were: total glycolytic volume on FDG-PET (P = 0.003), sarcomatoid histology (P < 0.0005), weight loss (P = 0.031), computed tomography stage (P = 0.015), and European Organization for Research and Treatment of Cancer good prognostic score (P = 0.049). In patients with epithelioid or biphasic histology, baseline total glycolytic volume remained predictive of survival in patients with (P = 0.01) or without (P = 0.018) previous pleurodesis. In multivariate analysis, no variable other than histology contributed to the model in patients with sarcomatoid histology; total glycolytic volume and weight loss contributed to the models in patients with nonsarcomatoid histology. computed tomography-assessed tumor-node-metastasis stage did not contribute to the model. A nomogram, which incorporates quantitative PET parameters and pleurodesis into prognostic information, is presented.

CONCLUSIONS

Sarcomatoid histology remains the strongest prognostic factor. In patients with non sarcomatoid disease, volumetric FDG-PET parameters are more predictive of survival than tumor-node-metastasis staging, suggesting that tumor volume and glycolytic activity may be more important determinants of prognosis in malignant pleural mesothelioma than anatomic extent of disease.

Prognostic factors for 100 patients with malignant pleural mesothelioma

The aim of this study was to investigate the effects of various clinical, laboratory characteristics, and therapeutic modalities on the survival of patients with malignant pleural mesothelioma. One hundred consecutive patients with a pathologically proven diagnosis of malignant pleural mesothelioma treated between 1993 and 2005 were included in the study. Using a Cox proportional hazard model, comorbidity, weight loss, breathlessness, and performance status were identified as independent prognostic factors. Comorbidity had interestingly favorable effect on the survival. Treated patients with chemotherapy had significantly longer survival than those treated with best supportive care. However, it was necessary to complete at least 6 cycles for a survival benefit. In conclusions, comorbidity information should be recorded in the recent prognostic studies. The drugs used for the comorbidity may improve survival.

Combined resection, intraperitoneal chemotherapy, and whole abdominal radiation for the treatment of malignant peritoneal mesothelioma

OBJECTIVE

We report a single-institution Phase I or II trial of surgical debulking, intraperitoneal chemotherapy, and immunotherapy followed by whole abdominal radiotherapy in patients with malignant peritoneal mesothelioma.

METHODS

Between 1997 and 2000, 27 patients with malignant peritoneal mesothelioma were enrolled: 23 with epithelial subtype and 4 with sarcomatoid or mixed subtype. The treatment regimen consisted of surgical debulking followed by 4 intraperitoneal courses of cisplatin alternating with 4 courses of doxorubicin, 4 doses of intraperitoneal gamma interferon, a second laparotomy with resection of residual disease plus intraoperative intraperitoneal mitomycin and cisplatin heated to 41 degrees C, and finally whole abdominal radiotherapy.

RESULTS

The median overall survival was 70 months with a 3-year survival of 67% (95% confidence interval, 46%-81%). Fourteen patients have died of their disease with a median time to death of 17 months (range, 0.4-71 months) after consenting to treatment. Seven patients are alive without evidence of disease with a median follow-up of 90 months (range, 71-110 months), and 6 are alive with disease with a median follow-up of 86 months (range, 70-106 months). The regimen was well tolerated. There were no patients with Grade III or IV hematological toxicities, 2 patients with Grade III ototoxicity, and 3 patients with Grade III gastrointestinal toxicity.

CONCLUSION

Based on the results of this study, intensive multimodality therapy appears feasible and effective in this group of patients.

Mesothelin-related predictive and prognostic factors in malignant mesothelioma: a nested case-control study

Soluble mesothelin-related protein (SMRP) in serum is potentially a sensitive marker of malignant mesothelioma (MM) diagnosis and progression, and may be useful as screening marker. Mesothelin expression in tumors is regarded as a sensitive marker for diagnosis and disease progression, and is a candidate prognostic marker. Levels of SMRP, CA125 and CYFRA 21-1 in pre-diagnostic (1-30 years) serum samples from 47 mesothelioma cases and 141 matched controls were analysed. Mesothelin expression in tumors was assessed. The association between biomarker level and mesothelioma risk and survival was analysed, adjusting for asbestos exposure. Survival related to tumor mesothelin expression, age, sex, histological type, location, asbestos exposure and pre-clinical SMRP was analysed. There was no significant association between biomarker levels and mesothelioma risk when analysed as continuous variables or as tertiles. Biomarker levels <10, 10-19 and >or=20 years before diagnosis were not significantly associated to mesothelioma risk. Mesothelin expressed in >50% of tumor cells was seen in 36 of 47 (77%) tumors. Mesothelin expression in <50% of tumor cells was a significant negative prognostic marker in all cases of malignant mesothelioma (median survival=6 months vs. 12 months, hazard ratio (HR)=2.49, 95%CI 1.17-5.27), and also when only epithelial mesothelioma was analysed (median=6 months vs. 14 months, HR=2.36, 95%CI 1.07-5.22). When adjusted for age and gender, the prognosis was still dismal, but non-significant (HR=1.85, 95%CI 0.85-4.05). High age (>65 years) was an independent negative prognostic factor that was related to both mesothelin expression and asbestos exposure. Mesothelioma of the epithelial type of the peritoneum had a significantly longer survival than epithelial type in pleura and was also related to mesothelin expression.

Incidence and descriptive epidemiology of mesothelioma in the United States, 1999-2002

To estimate the recent incidence of mesothelioma in the United States and characterize its descriptive epidemiology, incidence data were obtained from the National Program of Cancer Registries (NPCR) and the Surveillance, Epidemiology and End Results (SEER) Program. Age-adjusted incidence rates and 95% confidence intervals were calculated. The U.S. incidence was 1.11 cases per 100,000 persons. Most cases occurred among older, white males. However, 173 cases (< 2%) occurred in persons younger than 40. The proportion of women with peritoneal mesothelioma was triple that of men (14.8% vs 5.4%). Of 40 reporting states, 11 had incidence rates significantly higher than the national rate.

Prolonged survival due to spontaneous regression and surgical excision of malignant mesothelioma

We report a case of malignant pleural mesothelioma with histologically proven spontaneous regression of pleural disease. During a 12-year follow-up there was a single recurrence, which was a lesion in the chest wall at 6 years that was surgically excised. A prominent host response to tumor was seen in both the primary tumor and the recurrence.

Efficacy of a combination of pemetrexed and multiple redo-surgery in an 11-year-old girl with a recurrent multifocal abdominal mesothelioma

We report the case of an 11-year-old girl with a recurrent progressive locally advanced abdominal mesothelioma. First, there was an incomplete surgical resection without any complementary chemotherapy, followed by a slow progression of the disease. Three years later, after two macroscopically complete surgical resections of peritoneal and ovarian tumors, she failed to respond to treatment with gemcitabin-carboplatin and gemcitabin-cisplatin, and developed splenic tumors and large multicystic hepatic tumors. She was then treated with pemetrexed. The schedule of chemotherapy was pemetrexed 400 mg intravenously plus cisplatin 60 mg once every 3 weeks associated with folic acid and vitamin B12. The tumor reduction was evaluated with positron emission tomography scan and tomodensitometry every three courses. Chemotherapy tolerance was good apart from a grade III neutropenia at the second course, a fever of unknown origin at the fifth course and a grade III thrombocytopenia at the sixth course. As tolerance and clinical responses were good, pemetrexed posology was increased up to 10%. After six courses, hepatic and splenic lesion tumors were initially diminished and then stablilized. Thus, a surgical resection was attempted: a first surgery followed by a second one 3 days later allowed completion of a difficult left hepatectomy, and resection of the hilum and splenic tumors. Fourteen months after the surgery, the girl remained in partial remission with stable disease. So far, pemetrexed associated with cisplatin revealed a good tolerance and promising results regarding its antitumoral efficacy in a progressive metastatic abdominal mesothelioma in childhood.

Peritoneal mesothelioma treated by cytoreductive surgery and intraperitoneal hyperthermic chemotherapy: results of a prospective study

BACKGROUND

Peritoneal mesothelioma is a rare disease with few therapeutic options. Recently, the combination of cytoreductive surgery with intraperitoneal hyperthermic chemotherapy (HIPEC) has shown promising results.

METHODS

Fifteen patients with peritoneal mesothelioma who were treated by cytoreductive surgery and HIPEC between 1989 and 2004 were identified from a prospective database. HIPEC was performed with cisplatin and mitomycin C for 90 minutes by using the closed-abdomen technique.

RESULTS

All patients but one (multicystic) had malignant disease of the following pathologic types: 12 epithelial and 2 biphasic. After surgical resection, 11 patients were considered to have a CC-0 or CC-1 resection (macroscopic complete resection or diameter of residual nodules <2.5 mm). No postoperative death occurred, and six postoperative complications were recorded. All but one patient had resolution of ascites. The overall median survival for the 14 patients with malignant mesothelioma was 35.6 months. The median survival was 37.8 months for patients treated with a CC-0 or CC-1 resection, whereas it was 6.5 months for those treated with a CC-2 or CC-3 resection (diameter of residual nodules >2.5 mm; P < .001). In a univariate analysis, the only other significant prognostic factor was the carcinomatosis extent (P = .02).

CONCLUSIONS

A therapeutic strategy combining cytoreductive surgery with HIPEC seems to provide an adequate and efficient locoregional treatment for peritoneal mesothelioma. It is associated with acceptable morbidity when performed by an experienced surgical team. The completeness of cytoreduction is the major determinant of survival.

Survival of malignant pleural mesothelioma cases in the Tuscan Mesothelioma Register, 1988-2000: a population-based study

This study analyses survival of Tuscan residents (Italy, 3.5 million population) diagnosed by histological examination with malignant pleural mesothelioma (MPM) during the period 1988-2000, and recorded in the Tuscan Malignant Mesothelioma Register. The aim was to establish the prognostic role of demographic, diagnostic and asbestos exposure variables. During 1988-2000, 381 MPM cases were recorded (318 men; 63 women). Vital status was ascertained up to 31 December 2002. No cases were lost to follow-up. Median survival of certain MPM was 324 days (11 months; 95% CI 297-366); 45.7% (95% CI 40.6-50.6%) survived more than 1 year; 24.2% (95% CI 20.0-28.5%) more than 2 years. In univariate and multivariate analyses survival was associated with histological subtype (epithelioid subtype had the longest survival). Gender, age, period of diagnosis, hospital of diagnosis and asbestos exposure did not show significant effects. Therapeutic information was available for patients of the period 1997-2000. There was no significant difference in survival between treated versus untreated patients. In conclusion, no advance in prognosis at the population level in the most recent period can be suggested on the basis of the data available to the Tuscan Malignant Mesothelioma Register.

Prognostic factors in mesothelioma

Prognostic factors can help clinicians and patients when deciding a treatment plan. Patients in the best prognostic groups can be considered for more intensive or experimental therapy. Alternatively, patients in the best prognostic groups might prefer a period of observation prior to commencement of therapy. For patients with mesothelioma prognostic factors are potentially especially important because of the lack of a widely applicable anatomical staging system. Both the International Mesothelioma Interest Group (IMIG) and Brigham staging systems are of limited relevance to patients not undergoing radical debulking surgery. Radiological prediction of IMIG or Brigham stage is of little value. Review of the best-known prognostic scoring systems from the EORTC and CALGB has shown that the most important predictors of poor prognosis are: poor performance status; non-epithelioid histology; male gender; low hemoglobin; high platelet count; high white blood cell count; and high lactate dehydrogenase (LDH). The EORTC model was validated at St Bartholomew's Hospital in a group of 145 patients treated in sequential phase II chemotherapy trials. For 70 patients treated with vinorelbine, those having the best EORTC prognosis had a median survival of 19.2 months [95% C.I.=14.7-23.7] compared to 9.9 months [95% C.I.=8.5-11.3] for those in the worst group. The suggestion is that all clinical and biological factors relevant to prognosis should be recorded prospectively in mesothelioma patients selected for clinical trials.