Pleural mesothelioma incidence in Europe: evidence of some deceleration in the increasing trends

Asbestos ban policies and mesothelioma mortality in Greece

BACKGROUND

Malignant mesothelioma is a rare form of cancer that mostly affects the pleura and has a strong link to asbestos exposure. Greece banned the use of asbestos in 2005, however, the public was already aware of this substance in the 1980s. This research aims to present an overview of Greece's mesothelioma age-standardized mortality rates (ASMR) from 1983 to 2019 by age, gender, and geographic region and to determine whether the actions to ban asbestos impacted these rates.

METHODS

Data were retrieved by the Hellenic Statistical Authority (HSA) from death certificates that mentioned mesothelioma as the cause of death from 1983 to 2019 with details on the residence, gender, and age. Statistical analysis was performed using PRISM 6.0 software, a two-way ANOVA test, Trend analysis was conducted using Joinpoint Regression Program 5.0 software. The linear and non-linear model was used to calculate the age-standardized rates of annual percentage change (APC) and its 95% confidential interval (95% CI).

RESULTS

From 1983 to 2019, 850 total mesothelioma deaths were recorded, the majority of whom were males (634). A rate of 74.6% accounts for males and 25.4% for females, and the ratio of Males: Females was 3:1. Males' ASMR and the whole population's ASMR reached their highest levels in 2011 (0.93/100000person-years and 0.53/100000person-years, respectively). To look for potential changes between the first two decades of the 21st century, we compared the mean ASMR of each geographic region in Greece between two different 10-year subperiods (2000-2009 and 2010-2019). Except for Epirus, all regions of Greece had elevated regional ASMRs, particularly in those with the highest asbestos deposits. Notably, the ASMR in Epirus decreased from 0.54/100000person-years (2000-2009) to 0.31/100000person-years (2010-2019). After 2011, the ASMR for men and the general population stabilized. This stability is important since mesothelioma in men is associated with occupational asbestos exposure. The intriguing discovery of a lower ASMR in Epirus emphasizes the need to raise awareness of the condition and implement effective public health measures.

CONCLUSIONS

In Greece, the annual ASMR for males and the whole population reached its highest level in 2011, which is positive and encouraging and may be a sign that the rate will stabilize during the following years. Moreover, this study showed that the actions made in the 1980s regarding public awareness and surveillance directly impacted the decrease in Epirus rates. Future research, continual awareness, information, and recording are needed to monitor the mesothelioma epidemic. The possible benefit of a mesothelioma registry and the epidemiological surveillance of asbestos-related diseases, particularly mesothelioma mortality, need to be addressed.

TRIAL REGISTRATION

Not applicable.

Global Incidence, Risk Factors, and Temporal Trends of Mesothelioma: A Population-Based Study

INTRODUCTION

Mesothelioma is an uncommon type of cancer which has received little attention. This study aims to evaluate the global disease burden; trends of mesothelioma by age, sex, and geographic locations; and its risk factors on the population level.

METHODS

The Global Cancer Observatory, Cancer Incidence in Five Continents Plus, and Global Burden of Disease were accessed for mesothelioma incidence and its risk factors worldwide. The associations between mesothelioma incidence and asbestos were evaluated for each country by multivariable linear regression analysis by sex and age. Average annual percentage change (AAPC) was calculated using Joinpoint regression to evaluate the epidemiologic trends of mesothelioma.

RESULTS

The age-standardized rate of mesothelioma was 0.30 per 100,000 persons with Northern Europe reporting the highest incidence rates. The incidence rate of the male population was much higher than that of the females. Countries with higher human development index (β = 0.119, confidence interval [CI]: 0.073-0.166, p < 0.001), gross domestic product per capita (β = 0.133, CI: 0.106-0.161, p < 0.001), and asbestos exposure (β = 0.087, CI: 0.073-0.102, p < 0.001) had higher mesothelioma. The overall trend of mesothelioma incidence was decreasing, although an increase was observed in Bulgaria (AAPC: 5.56, 95% CI: 2.94-8.24, p = 0.001) and Korea (AAPC: 3.24, 95% CI: 0.08-6.49, p = 0.045).

CONCLUSIONS

There was a substantial declining incidence trend of mesothelioma in the past decade possibly related to the restriction of the use of asbestos in some countries. Meanwhile, the increasing trend in mesothelioma incidence observed in females might be indicative of an increase in environmental exposure to mineral fibers.

Pleural mesothelioma risk by industry and occupation: results from the Multicentre Italian Study on the Etiology of Mesothelioma (MISEM)

BACKGROUND

The Italian mesothelioma registry (ReNaM) estimates mesothelioma incidence and addresses its etiology by assessing cases' exposures but cannot provide relative risk estimates.

OBJECTIVES

i) To estimate pleural mesothelioma relative risk by industry and occupation and by ReNaM categories of asbestos exposure; and ii) to provide quantitative estimates of the exposure-response relationship.

METHODS

A population-based mesothelioma case-control study was conducted in 2012-2014 in five Italian regions. Cases and age and gender frequency-matched controls were interviewed using a standard ReNaM questionnaire. Experts coded work histories according to international standard classifications of industries/occupations and assigned asbestos exposure according to ReNaM categories. Job codes were further linked to SYN-JEM, a quantitative job-exposure matrix. Cumulative exposure (CE, f/mL-years) was computed by summing individual exposures over lifetime work history. Unconditional logistic regression analyses adjusted by gender, centre and age were fitted to calculate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Among men we observed increased risks of mesothelioma in many industries and associated occupations, including: asbestos-cement (OR = 3.43), manufacture of railroad equipment (OR = 8.07), shipbuilding and repairing (OR = 2.34), iron and steel mills (OR = 2.15), and construction (OR = 1.94). ORs by ReNaM exposure categories were as follows: definite/probable occupational exposure (OR = 15.8, men; OR = 8.80, women), possible occupational (OR = 2.82, men; OR = 3.70, women), sharing home with an exposed worker (OR = 2.55, men; OR = 10.3, women), residential (OR = 2.14, men; OR = 3.24, women). Based on SYN-JEM, mesothelioma risk increased by almost 30% per f/mL-year (OR = 1.28, CI 1.16-1.42).

CONCLUSIONS

Out study involved five regions with historically different types and levels of industrial development, encompassing one third of the Italian population and half of Italian mesothelioma cases. As expected, we found increased pleural mesothelioma risk in the asbestos industry and in trades with large consumption of asbestos materials. Clear associations were found using both qualitative (ReNaM classifications) and quantitative estimates (using SYN-JEM) of past asbestos exposure, with clear evidence of an exposure-response relationship.

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.

Immune checkpoint inhibitors a new player in the therapeutic game of mesothelioma: New reality with new challenges

Malignant pleural mesothelioma (MPM) is a rare and orphan thoracic malignancy, with a poor prognosis as the majority of patients are diagnosed with unresectable MPM, with no significant improvements in the therapeutic strategy for over a decade. However, the recent approval of immune checkpoint inhibitors (ICI) in treatment-naïve patients with unresectable MPM marks a significant step forward and hope for the treatment of this disease. In this narrative review, we discuss the biological rationale to use ICI in the treatment of MPM. We summarize the current evidence for the efficacy of ICI in MPM and discuss several unresolved challenges regarding the use of ICI in this disease, such as the best upfront immune approach in MPM (ICI versus ICI plus chemotherapy), the optimal sequential treatment strategy according to the first-line treatment, and the potential role of predictive biomarkers.

Association Between Folate and Health Outcomes: An Umbrella Review of Meta-Analyses

Background: There is no study that has systematically investigated the breadth and validity of the associations of folate and multiple health outcomes. We aimed to evaluate the quantity, validity, and credibility of evidence regarding associations between folate and multiple health outcomes by using umbrella review of meta-analysis. Methods: We searched the MEDLINE, EMBASE, and Cochrane Library databases from inception to May 20, 2018, to identify potential meta-analyses that examined the association of folate with any health outcome. For each included meta-analysis, we estimated the summary effect size and their 95% confidence interval using the DerSimonian and Laird random-effects model. We used the AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews) to assess methodological quality and the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation working group classification) to assess the quality of evidence for each outcome included in the umbrella review. Results: Overall, 108 articles reporting 133 meta-analyses of observational studies and 154 meta-analyses of randomized controlled trials (RCTs) were included in the study. Among them, 108 unique exposure-outcome-population triplets (referred to as unique meta-analyses hereafter) of RCTs and 87 unique meta-analyses of observational studies were reanalyzed. Beneficial effects of folate were observed in the all-cause mortality rate and in a number of chronic diseases, including several birth/pregnancy outcomes, several cancers, cardiovascular disease and metabolic-related outcomes, neurological conditions, and several other diseases. However, adverse effects of folate were observed for prostate cancer, colorectal adenomatous lesions, asthma or wheezing, and wheezing as an isolated symptom and depression. Conclusions: Current evidence allows for the conclusion that folate is associated with decreased risk of all-cause mortality and a wide range of chronic diseases. However, folate may be associated with an increased risk of prostate cancer. Further research is warranted to improve the certainty of the estimates.

Imaging of asbestos-related lung and pleural diseases as an endemic exposure in Egypt

Background

Asbestos refers to a group of naturally occurring silicate minerals which have been traditionally used in building materials and household products. Inhalation of asbestos fibers, however, has been associated with adverse health outcomes, with the disease manifestations principally affecting the thorax. The aim of our study is to detect and evaluate the different radiological patterns of asbestos-related lung and pleural disease and its complications

Results

MDCT examination was able to assess and distinguish asbestosis as well as asbestos-related lung and pleural disease besides detection of any associated complications.

Conclusion

This study demonstrates that while reporting of malignant asbestos-related pleural disease is adequate, there is room for improvement in the reporting of more benign disease.

Malignant pleural mesothelioma: Treatment patterns and outcomes from the Spanish Lung Cancer Group

BACKGROUND

Malignant mesothelioma is a rare but aggressive tumor arising from the pleura, typically associated with exposure to asbestos. The purpose of this investigation was to describe mesothelioma patient characteristics, treatment patterns, and outcomes in Spain.

MATERIAL AND METHODS

Patients diagnosed with malignant mesothelioma of the pleura were recorded in an anonymous online database (BEMME, Epidemiologic Spanish Malignant Mesothelioma Database) from June 2008 through May 2013. Patient and tumor characteristics at time of diagnosis, as well as subsequent treatments (surgery, radiation, and chemotherapy), were collected. Among patients treated with chemotherapy, we explored type of chemotherapy regimen and outcomes by treatments.

RESULTS

A total of 560 malignant pleural mesothelioma (MPM) patients were recorded. The median age at diagnosis was 68 years, mainly with epithelioid histology (62 %), and any asbestos exposure was noted in 45 % of patients. Nearly two-thirds of patients (71 %) received chemotherapy, mainly platinum-pemetrexed combination, as part of their treatment. Surgery and radiotherapy were given in 36 % and 17 % of patients, respectively. The median overall survival (OS) in the whole cohort was 13.0 months (95 % confidence interval (CI), 11.1-14.8 months) with 1-year OS of 53.2 % (95 % CI, 48.7-57.7 %). In patients receiving first-line chemotherapy (N = 315), the median OS was 13.4 months (95 % CI, 10.8-16.0 months), reaching 20.2 months (95 % CI, 17.2-23.2 months) for those 68 patients receiving maintenance chemotherapy. Results of multivariate analyses showed significant association of ECOG-performance status, histology and treatment response with improved OS in MPM patients treated with palliative chemotherapy.

CONCLUSIONS

Despite multimodal therapeutic intervention, survival of patients with mesothelioma in Spain remains poor. Although it did not reach significance in the multivariate analysis, a meaningful additional survival benefit was observed among those patients receiving maintenance chemotherapy.

Treatment patterns among patients with malignant pleural mesothelioma: An Italian, population-based nationwide study

Background

Malignant pleural mesothelioma (MPM) is a rare cancer with a poor prognosis. Centralization of rare cancer in dedicated centers is recommended to ensure expertise, multidisciplinarity and access to innovation. In Italy, expert centers for MPM have not been identified in all regions. We aimed to describe the treatment patterns among MPM patients across different Italian regions and to identify factors associated with the treatment patterns across the regions.

Methods

We performed an observational study on a random sample of 2026 MPM patients diagnosed in 2003–2008. We included 26 population‐based registries covering 70% of the Italian population. To identify factors associated with treatment patterns, across the different regions, we fitted a multinomial logistic regression model adjusted by age, sex, stage, histology and hospital with thoracic surgical department.

Results

MPM patients mostly received chemotherapy alone (41%) or no cancer‐directed therapy (36%) especially the older patients. The first course of treatment for MPM patients differed across regions. Patients from Piedmont, Liguria and Campania were more likely to receive no cancer‐directed therapy; those living in Tuscany and Sicily were more likely to get surgery; patients from Marche and Lazio were more likely to receive chemotherapy. These differences were not explained by age, sex, stage, histology and availability of a thoracic surgery department.

Conclusions

There is limited expertise available and lack of a network able to maximize the expertise available may contribute to explaining the results of our study. Our findings support the need to ensure the appropriate care of all MPM patients in reorganizing the health care services.

Key points

Predictions of Mortality from Pleural Mesothelioma in Italy After the Ban of Asbestos Use

Even if the epidemic of malignant pleural mesothelioma (MPM) is still far from being over worldwide, the health effects of regulations banning asbestos can be evaluated in the countries that implemented them early. Estimates of MPM future burden can be useful to inform and support the implementation of anti-asbestos health policies all around the world. With this aim we described the trends of MPM deaths in Italy (1970-2014) and predicted the future number of cases in both sexes (2015-2039), with consideration of the national asbestos ban that was issued in 1992. The Italian National Statistical Institute (ISTAT) provided MPM mortality figures. Cases ranging from 25 to 89 years of age were included in the analysis. For each five-year period from 1970 to 2014, mortality rates were calculated and age-period-cohort Poisson models were used to predict future burden of MPM cases until 2039. During the period 1970-2014 a total number of 28,907 MPM deaths were observed. MPM deaths increased constantly over the study period, ranging from 1356 cases in 1970-1974 to 5844 cases in 2010-2014. The peak of MPM cases is expected to be reached in the period 2020-2024 (about 7000 cases). The decrease will be slow: about 26,000 MPM cases are expected to occur in Italy during the next 20 years (2020-2039). The MPM epidemic in Italy is far from being concluded despite the national ban implemented in 1992, and the peak is expected in 2020-2024, in both sexes. Our results are consistent with international literature.

Mesothelioma Mortality Rates in Greece for the Period 2005-2015 Is Increased Compared to Previous Decades

Background and Objective: To present summary statistics regarding malignant mesothelioma (MM) mortality in Greece during the period 2005–2015 and compare it with previous decades, along with gender, age and geographical area analysis. Materials and Methods: The Hellenic Statistical Authority provided the data, which included all deaths for the period 1983 to 2015 that mentioned MM as the death cause in the corresponding death certificate. MM mortality rates have been calculated with respect to gender, age, and geographical location in Greece. Furthermore, a comparison analysis was made among three eleven consecutive year periods, in order to assess potential changes in the mortality rates. Results: The MM mortality rate has significantly increased during the period 2005–2015 both in males and females compared to earlier decades. The maximum number of MM deaths has shifted to an older age group of 70–80 years during the 2005–2015 period as compared to that of 1983–2004 in both genders. Additionally, MM mortality rates have significantly increased in all geographical areas except for the Epirus Prefecture. Conclusions: Our results demonstrate an increased MM mortality rate in Greece for the decade 2005–2015 as compared to the two previous decades. This increase is possibly due to the fact that the peak in asbestos production and use in Greece was in mid 1990s, while the asbestos ban came in effect in 2005. Based on these findings the MM epidemic in Greece has not yet peaked, therefore it is important to implement screening strategies for early MM detection.

Epidemiology of Mesothelioma

Since 1973 the International Agency for Research on Cancer has classified asbestos as a certain carcinogen, but today it is still used in several countries. To date, mesothelioma risk is certainly linked not only to occupational exposures but also to environmental exposures. The incidence and mortality are increasing worldwide, especially in developing countries where asbestos is still often used without adequate measures for worker safety. The epidemiological surveillance systems of related asbestos diseases are instruments of public health adopted internationally. The experience and the operating methodology of the Italian mesothelioma registry and the data produced from 1996 to 2015 highlight how in countries where the asbestos ban has been active for over 20 years the risk of asbestos remains present, especially in the construction sector as well as for the environmental exposures of the resident population near companies that used asbestos in their production cycle. Worldwide, it is necessary to introduce the ban on the extraction, processing, and marketing of asbestos as claimed by the international scientific community.

Analyzing biological and molecular characteristics and genomic damage induced by exposure to asbestos

Asbestos is one of the most important occupational carcinogens. Currently, about 125 million people worldwide are exposed to asbestos in the workplace. According to global estimates, at least 107,000 people die each year from lung cancer, mesothelioma, and asbestosis as a result of occupational exposure to asbestos. The high pathogenicity of this material is currently known, being associated with the development of pulmonary diseases, of which lung cancer is the main cause of death due to exposure to this mineral. Pulmonary diseases related to asbestos are a common clinical problem and a major health concern worldwide. Extensive research has identified many important pathogenic mechanisms; however, the precise molecular mechanisms involved, and the generated genomic damage that lead to the development of these diseases, are not completely understood. The modes of action that underlie this type of disease seem to differ depending on the type of fiber, lung clearance, and genetics. This evidences the need to increase our knowledge about these effects on human health. This review focuses on the characteristics of asbestos and the cellular and genomic damage generated in humans via exposure.

Malignant pleural mesothelioma in Finland: regional and gender variation

BACKGROUND

Malignant pleural mesothelioma (MPM) is a rare occupational cancer with a poor prognosis. Even with a multimodality treatment approach, the treatment outcomes remain unsatisfactory. The use of asbestos has been banned in most developed countries, but MPM continues to be a significant occupational disease also in these countries. Aim of this study is to identify modern epidemiology and assess equality in care.

METHODS

Our study cohort consists of 1010 patients diagnosed with MPM in Finland during 2000-2012. The data were collected from the Finnish Cancer Registry, the National Workers' Compensation Center Registry and the National Registry of Causes of Death, Statistics Finland.

RESULTS

Women were diagnosed a mean of 4.5 years later than males (p = .001), but survival did not differ (overall median survival 9.7 months). A workers' compensation claim was more common in males (OR 11.0 [95% CI 7.5-16.2]) and in regions with a major asbestos industry (OR 1.7 [95% CI 1.3-2.2]). One-year and three-year survivals did not differ regionally. Patients without chemotherapy treatment had an inferior survival (RR 1.8 [95% CI 1.5-2.0]). The initial survival benefit gained with pemetrexed was diluted at 51 months.

CONCLUSIONS

MPM is a disease with a poor prognosis, although chemotherapy appears to improve survival time. Significant gender and regional variation exists among patients, with notable differences in diagnostic and treatment practices. Long-term outcomes with pemetrexed remain indeterminate.

IMPACT

Emphasize centralized consult services for the diagnosis, treatment and support that patients receive for MPM, facilitating equal outcomes and compensation.

Hotspots of malignant pleural mesothelioma in Western Europe

Malignant pleural mesothelioma, a highly invasive tumour, has been epidemiologically linked to an occupational or environmental exposure to asbestos. Although asbestos has been widely used in diverse industrial applications and in construction, some industrial sectors have been affected much more than others. The objective of this review was to describe the existence of clusters of malignant pleural mesothelioma in Western European countries, based on epidemiological studies published between 2000 and 2015. MEDLINE (PubMed) and Embase were searched for relevant studies on spatial clustering of mesothelioma in Western European countries. Eventually, 16 different studies published between 2000 and 2015 were selected for a comprehensive analysis. Relevant studies on spatial clustering of mesothelioma were found for Belgium, the Netherlands, the United Kingdom, Germany, France, Spain, Italy and Denmark. Clustering of pleural mesothelioma was found mainly around shipyards (16 studies) and asbestos cement industries (10 studies). Although malignant pleural mesothelioma may be found throughout Western Europe, the present study indicates specific areas with higher past and also probable future incidence.

Nonspecific pleuritis: optimal duration of follow-up

BACKGROUND

Nonspecific pleuritis (NSP) is a frequent diagnosis after parietal pleural biopsy, but the clinical significance of this finding and need for further follow-up have not been firmly established. Previous reports suggest that 5% to 25% of patients with NSP are subsequently diagnosed with pleural malignancy.

METHODS

Our pathology database was queried for patients with histologic evidence of NSP from January 01, 2001, to December 31, 2012 (n = 413). Patients with less than 1 year of follow-up after biopsy, diagnosis of empyema, tuberculous pleuritis, active systemic connective tissue disease or vasculitis, or active malignancy were excluded (n = 327). The remaining patients were included and their medical records were reviewed.

RESULTS

Eighty-six patients were included. Mean follow up was 1,824 ± 1,032 days (range, 409 to 4,599 days). Three of the 86 patients with NSP (3.5%) were subsequently diagnosed with pleural malignancy. All 3 patients were found to have mesothelioma with a mean time from biopsies to diagnosis of 205 ± 126 days (range, 64 to 306 days). Twenty-two of 86 patients (25.5%) had a possible identifiable cause of pleural inflammation (benign disease). After exclusion of these 22 patients, the incidence of malignancy was 3 of 64 (4.7%).

CONCLUSIONS

The incidence of subsequent pleural malignancy (mesothelioma) among patients found to have NSP based on pleural biopsy was 3.5%. Occult mesothelioma in patients with NSP will most likely be diagnosed within 1 year of the initial pleural biopsy; therefore, these patients should be followed for a minimum of 1 year to allow for timely detection of occult pleural malignancy.

Asbestos in Belgium: an underestimated health risk. The evolution of mesothelioma mortality rates (1969-2009)

Background:

Although Belgium was once a major international manufacturer of asbestos products, asbestos-related diseases in the country have remained scarcely researched.

Objectives:

The aim of this study is to provide a descriptive analysis of Belgian mesothelioma mortality rates in order to improve the understanding of asbestos health hazards from an international perspective.

Methods:

Temporal and geographical analyses were performed on cause-specific mortality data (1969–2009) using quantitative demographic measures. Results were compared to recent findings on global mesothelioma deaths.

Results:

Belgium has one of the highest mesothelioma mortality rates in the world, following the UK, Australia, and Italy. With a progressive increase of male mesothelioma deaths in the mid-1980s, large differences in mortality rates between sexes are apparent. Mesothelioma deaths are primarily concentrated in geographic areas with proximity to former asbestos industries.

Conclusions:

Asbestos mortality in Belgium has been underestimated for decades. Our findings suggest that the location of asbestos industries is correlated with rates of mesothelioma, underlining the need to avert future asbestos exposure by thorough screening of potential contaminated sites and by pursuing a global ban on asbestos.

Nonselective transarterial chemoperfusion: a palliative treatment for malignant pleural mesothelioma

PURPOSE

To evaluate tumor response by means of volumetric assessment, survival, and changes in patient symptoms after the treatment of unresectable and/or recurrent pleural mesothelioma by using regional nonselective transarterial chemoperfusion as a palliative treatment option.

MATERIALS AND METHODS

This retrospective study was approved by the hospital ethical committee, and all patients signed an informed consent prior to treatment. Thirty-nine patients (mean age, 64.0 years; 10 women and 29 men) with unresectable pleural mesothelioma were treated with repetitive transarterial chemoperfusion between March 2007 and March 2010, with a mean of 2.9 sessions per patient at 4-week intervals. Transarterial chemoperfusion was performed by using mitomycin C, cisplatin, and gemcitabine. Computed tomography findings and patient symptoms were evaluated. Tumor response was evaluated by using Response Evaluation Criteria in Solid Tumors guidelines, and survival was assessed with the Kaplan-Meier method. The change in volume for the partial-response group was tested by using the Wilcoxon signed-rank test.

RESULTS

In 36% of treated tumors (14 of 39), partial response was achieved, and tumor volume decreased from a mean value ± standard deviation of 839.6 mL ± 590.3 (range, 3.9-1972.2 mL) to 137 mL ± 399.8 (range, 0.88-1131.4; P = .00012). In 49% of tumors (19 of 39), stable disease was noted. In 15% of tumors (six of 39), progressive disease was seen. Mean specific growth rate of the tumor was 0.00158% per day. The mean survival time was 14.2 months (range, 2.1-33.1 months) from the start of treatment. For patients with tumors that responded to treatment, mean survival time was 15 months (range, 4.5-33.1 months). Mean time to disease progression was 2.6 months for all tumors, 1.5 months for stable disease, and 1.3 months for progressive disease.

CONCLUSION

Transarterial chemoperfusion may have the potential to yield positive results and response in the treatment of recurrent and/or unresectable pleural mesothelioma. © RSNA, 2012.

Elimination of asbestos use and asbestos-related diseases: an unfinished story

Asbestos is a proven human carcinogen. Asbestos-related diseases (ARDs) typically comprise lung cancer, malignant mesothelioma, asbestosis, pleural plaques, thickening and effusion. International organizations, notably the World Health Organization and the International Labour Organization, have repeatedly declared the need to eliminate ARDs, and have called on countries to stop using asbestos. However, the relevant national-level indicators (e.g., incidence/mortality rates and per capita asbestos use, as well as their interrelationships) indicate that ARDs are increasing and asbestos use is continuing in the world. Lessons learned by industrialized countries in terms of policy and science have led to a growing number of countries adopting bans. In contrast, industrializing countries are faced with a myriad of forces prompting them to continue using asbestos. Full-scale international cooperation will thus be needed, with industrialized countries sharing their experiences and technologies to enable industrializing countries to make smooth transitions to banned states and achieve the goal of eliminating ARDs.

Rare thoracic cancers, including peritoneum mesothelioma

Rare thoracic cancers include those of the trachea, thymus and mesothelioma (including peritoneum mesothelioma). The aim of this study was to describe the incidence, prevalence and survival of rare thoracic tumours using a large database, which includes cancer patients diagnosed from 1978 to 2002, registered in 89 population-based cancer registries (CRs) and followed-up to 31st December 2003. Over 17,688 cases of rare thoracic cancers were selected based on the list of the RACECARE project. Mesothelioma was the most common tumour (19 per million per year) followed by epithelial tumours of the trachea and thymus (1.3 and 1.7, respectively). The age standardised incidence rates of epithelial tumours of the trachea was double in Eastern and Southern Europe versus the other European regions: 2 per million per year. Epithelial tumours of the thymus had the lowest incidence in Northern and Eastern Europe and UK and Ireland(1) and somewhat higher incidence in Central and Southern Europe.(2) Highest incidence in mesothelioma was seen in UK and Ireland(23) and lowest in Eastern Europe.(4) Patients with tumours of the thymus had the best prognosis (1-year survival 85%, 66% at 5 years). Five year survival was lowest for the mesothelioma 5% compared to 14% of patients with tumours of the trachea. Mesothelioma was the most prevalent rare cancer (12,000 cases), followed by thymus (7000) and trachea (1400). Cancer Registry (CR) data play an important role in revealing the burden of rare thoracic cancers and monitoring the effect of regulations on asbestos use and smoking related policies.

Applying quality criteria to exposure in asbestos epidemiology increases the estimated risk

Mesothelioma deaths due to environmental exposure to asbestos in The Netherlands led to parliamentary concern that exposure guidelines were not strict enough. The Health Council of the Netherlands was asked for advice. Its report has recently been published. The question of quality of the exposure estimates was studied more systematically than in previous asbestos meta-analyses. Five criteria of quality of exposure information were applied, and cohort studies that failed to meet these were excluded. For lung cancer, this decreased the number of cohorts included from 19 to 3 and increased the risk estimate 3- to 6-fold, with the requirements for good historical data on exposure and job history having the largest effects. It also suggested that the apparent differences in lung cancer potency between amphiboles and chrysotile may be produced by lower quality studies. A similar pattern was seen for mesothelioma. As a result, the Health Council has proposed that the occupational exposure limit be reduced from 10 000 fibres m(-3) (all types) to 250 f m(-3) (amphiboles), 1300 f m(-3) (mixed fibres), and 2000 f m(-3) (chrysotile). The process illustrates the importance of evaluating quality of exposure in epidemiology since poor quality of exposure data will lead to underestimated risk.

Global mesothelioma deaths reported to the World Health Organization between 1994 and 2008

OBJECTIVE

To carry out a descriptive analysis of mesothelioma deaths reported worldwide between 1994 and 2008.

METHODS

We extracted data on mesothelioma deaths reported to the World Health Organization mortality database since 1994, when the disease was first recorded. We also sought information from other English-language sources. Crude and age-adjusted mortality rates were calculated and mortality trends were assessed from the annual percentage change in the age-adjusted mortality rate.

FINDINGS

In total, 92,253 mesothelioma deaths were reported by 83 countries. Crude and age-adjusted mortality rates were 6.2 and 4.9 per million population, respectively. The age-adjusted mortality rate increased by 5.37% per year and consequently more than doubled during the study period. The mean age at death was 70 years and the male-to-female ratio was 3.6:1. The disease distribution by anatomical site was: pleura, 41.3%; peritoneum, 4.5%; pericardium, 0.3%; and unspecified sites, 43.1%. The geographical distribution of deaths was skewed towards high-income countries: the United States of America reported the highest number, while over 50% of all deaths occurred in Europe. In contrast, less than 12% occurred in middle- and low-income countries. The overall trend in the age-adjusted mortality rate was increasing in Europe and Japan but decreasing in the United States.

CONCLUSION

The number of mesothelioma deaths reported and the number of countries reporting deaths increased during the study period, probably due to better disease recognition and an increase in incidence. The different time trends observed between countries may be an early indication that the disease burden is slowly shifting towards those that have used asbestos more recently.

Pleural mesothelioma in New Caledonia: associations with environmental risk factors

BACKGROUND

High incidences of malignant mesothelioma (MM) have been observed in New Caledonia. Previous work has shown an association between MM and soil containing serpentinite.

OBJECTIVES

We studied the spatial and temporal variation of MM and its association with environmental factors.

METHODS

We investigated the 109 MM cases recorded in the Cancer Registry of New Caledonia between 1984 and 2008 and performed spatial, temporal, and space-time cluster analyses. We conducted an ecological analysis involving 100 tribes over a large area including those with the highest incidence rates. Associations with environmental factors were assessed using logistic and Poisson regression analyses.

RESULTS

The highest incidence was observed in the Houaïlou area with a world age-standardized rate of 128.7 per 100,000 person-years [95% confidence interval (CI), 70.41-137.84]. A significant spatial cluster grouped 18 tribes (31 observed cases vs. 8 expected cases; p = 0.001), but no significant temporal clusters were identified. The ecological analyses identified serpentinite on roads as the greatest environmental risk factor (odds ratio = 495.0; 95% CI, 46.2-4679.7; multivariate incidence rate ratio = 13.0; 95% CI, 10.2-16.6). The risk increased with serpentinite surface, proximity to serpentinite quarries and distance to the peridotite massif. The association with serpentines was stronger than with amphiboles. Living on a slope and close to dense vegetation appeared protective. The use of whitewash, previously suggested to be a risk factor, was not associated with MM incidence.

CONCLUSIONS

Presence of serpentinite on roads is a major environmental risk factor for mesothelioma in New Caledonia.

Solid cancer mortality associated with chronic external radiation exposure at the French atomic energy commission and nuclear fuel company

Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar period, company and socioeconomic status (SES)]. During the period 1968-2004, there were 2,035 solid cancers among the 36,769 CEA-AREVA NC workers. Cumulative external radiation exposure was assessed for the period 1950-2004, and the mean cumulative dose was 12.1 mSv. Mortality rates for all causes and all solid cancers were both significantly lower in this cohort than in the general population. A significant excess of deaths from pleural cancer, not associated with cumulative external dose, was observed, probably due to past asbestos exposure. We observed a significant excess of melanoma, also unassociated with dose. Although cumulative external dose was not associated with mortality from all solid cancers, the central estimated excess relative risk (ERR) per Sv of 0.46 for solid cancer mortality was higher than the 0.26 calculated for male Hiroshima and Nagasaki A-bomb survivors 50 years or older and exposed at the age of 30 years or older. The modification of our results after stratification for SES demonstrates the importance of this characteristic in occupational studies, because it makes it possible to take class-based lifestyle differences into account, at least partly. These results show the great potential of a further joint international study of nuclear workers, which should improve knowledge about the risks associated with chronic low doses and provide useful risk estimates for radiation protection.

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

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

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

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

Malignant pleural mesothelioma risk among nuclear workers: a review

Exposure to ionising radiation has been suggested as a causal risk factor for malignant pleural mesothelioma (MPM). Studies of patients treated by radiotherapy for primary cancers have suggested that radiation contributes to the development of secondary MPM. Here we examined the risk to nuclear workers of MPM related to exposure to low doses of occupational radiation at low dose rates. All results concerning MPM risk in published studies of nuclear workers were examined for their association with radiation exposure and potential confounders. We found 19 relevant studies. Elevated risks of pleural cancer were reported in most (15/17) of these studies. Eight reported risks higher for radiation monitored workers than for other workers. However, of 12 studies that looked at associations with ionising radiation, only one reported a significant dose-risk association. Asbestos was an important confounder in most studies. We conclude that studies of nuclear workers have not detected an association between ionising radiation exposure and MPM. Further investigations should improve the consideration of asbestos exposure at the same time as they address the risk of MPM related to occupational exposure of nuclear workers to low doses of ionising radiation at low dose rates.

Malignant peritoneal mesothelioma

Malignant mesothelioma is a highly aggressive neoplasm. The incidence of malignant mesothelioma is increasing worldwide. Diffuse malignant peritoneal mesothelioma (DMPM) represents one-fourth of all mesotheliomas. Association of asbestos exposure with DMPM has been observed, especially in males. The great majority of patients present with abdominal pain and distension, caused by accumulation of tumors and ascitic fluid. In the past, DMPM was considered a pre-terminal condition; therefore attracted little attention. Patients invariably died from their disease within a year. Recently, several prospective trials have demonstrated a median survival of 40 to 90 mo and 5-year survival of 30% to 60% after combined treatment using cytoreductive surgery and perioperative intraperitoneal chemotherapy. This remarkable improvement in survival has prompted new search into the medical science related to DMPM, a disease previously ignored as uninteresting. This review article focuses on the key advances in the epidemiology, diagnosis, staging, treatments and prognosis of DMPM that have occurred in the past decade.

The health impact of nonoccupational exposure to asbestos: what do we know?

The objective of this study was to examine the epidemiological data that confirm the risks of pleural mesothelioma, lung cancer, and other respiratory damage associated with nonoccupational exposure to asbestos, in circumstances where exposure levels are usually lower than those found in the workplace: domestic and paraoccupational exposure to asbestos-containing material among people living with asbestos workers or near asbestos mines and manufacturing plants, environmental exposure from naturally occurring asbestos in soil, and nonoccupational exposure to asbestos-containing material in buildings. Studies concerning natural asbestos in the environment show that the exposure that begins at birth does not seem to affect the duration of the latency period, but the studies do not show whether early exposure increases susceptibility; they do not suggest that susceptibility differs according to sex. Solid evidence shows an increased risk of mesothelioma among people whose exposure comes from a paraoccupational or domestic source. The risk of mesothelioma associated with exposure as result of living near an industrial asbestos source (mines, mills, asbestos processing plants) is clearly confirmed. No solid epidemiological data currently justify any judgment about the health effects associated with passive exposure in buildings containing asbestos. Most of the studies on nonoccupational sources reported mainly amphibole exposure, but it cannot be ruled out that environmental exposure to chrysotile may also cause cancer. Nonoccupational exposure to asbestos may explain approximately 20% of the mesotheliomas in industrialized countries, but it is does not seem possible to estimate the number of lung cancers caused by these circumstances of exposure.

Asbestos-related occupational cancers compensated under the Industrial Accident Compensation Insurance in Korea

Compensation for asbestos-related cancers occurring in occupationally-exposed workers is a global issue; this is also an issue in Korea. To provide basic information regarding compensation for workers exposed to asbestos, 60 cases of asbestos-related occupational lung cancer and mesothelioma that were compensated during 15 yr; from 1993 (the year the first case was compensated) to 2007 by the Korea Labor Welfare Corporation (KLWC) are described. The characteristics of the cases were analyzed using the KLWC electronic data and the epidemiologic investigation data conducted by the Occupational Safety and Health Research Institute (OSHRI) of the Korea Occupational Safety and Health Agency (KOSHA). The KLWC approved compensation for 41 cases of lung cancer and 19 cases of mesothelioma. Males accounted for 91.7% (55 cases) of the approved cases. The most common age group was 50-59 yr (45.0%). The mean duration of asbestos exposure for lung cancer and mesothelioma cases was 19.2 and 16.0 yr, respectively. The mean latency period for lung cancer and mesothelioma cases was 22.1 and 22.6 yr, respectively. The major industries associated with mesothelioma cases were shipbuilding and maintenance (4 cases) and manufacture of asbestos textiles (3 cases). The major industries associated with lung cancer cases were shipbuilding and maintenance (7 cases), construction (6 cases), and manufacture of basic metals (4 cases). The statistics pertaining to asbestos-related occupational cancers in Korea differ from other developed countries in that more cases of mesothelioma were compensated than lung cancer cases. Also, the mean latency period for disease onset was shorter than reported by existing epidemiologic studies; this discrepancy may be related to the short history of occupational asbestos use in Korea. Considering the current Korean use of asbestos, the number of compensated cases in Korea is expected to increase in the future but not as much as developed countries.

Survival of pleural malignant mesothelioma in Italy: a population-based study

A median survival time of about 9 months is generally reported among malignant pleural mesothelioma cases. Recently, better results in terms of survival and performance status have been reported in clinical trials that included highly selected patients. We describe the survival of pleural mesothelioma patients and the factors predictive of survival in an unselected, population-based setting. Pleural mesothelioma cases (4,100) registered from 1990 to 2001 by 9 Italian regional mesothelioma registries contributing to the network of the National Mesothelioma Registry were followed until December 31, 2005. Univariate (Kaplan-Meier) and multivariate (Cox proportional hazards regression) analyses of survival were carried out according to selected individual characteristics, including limited information on treatment in a subset of 578 cases. The median survival time was 9.8 months (95% confidence interval: 9.4-10.1). In multivariate analysis, younger age at diagnosis and epithelioid histotype were associated with significantly reduced hazard ratios. Positive effects of gender (women) and being diagnosed in a hospital with a thoracic surgery unit were of border-line statistical significance. No association with calendar period of diagnosis or asbestos exposure was present. Treatment was not associated with a statistically significant improvement in survival. This is the largest population-based study on survival in patients with pleural mesothelioma to date. Age and morphology were the main prognostic factors. Results regarding the effect of treatment were disappointing but may be useful to assess the future impact, at the population level, of recently introduced therapies.

Recent mortality from pleural mesothelioma, historical patterns of asbestos use, and adoption of bans: a global assessment

BACKGROUND

In response to the health risks posed by asbestos exposure, some countries have imposed strict regulations and adopted bans, whereas other countries have intervened less and continue to use varying quantities of asbestos.

OBJECTIVES

This study was designed to assess, on a global scale, national experiences of recent mortality from pleural mesothelioma, historical trends in asbestos use, adoption of bans, and their possible interrelationships.

METHODS

For 31 countries with available data, we analyzed recent pleural mesothelioma (International Classification of Diseases, 10th Revision) mortality rates (MRs) using age-adjusted period MRs (deaths/million/year) from 1996 to 2005. We calculated annual percent changes (APCs) in age-adjusted MRs to characterize trends during the period. We characterized historical patterns of asbestos use by per capita asbestos use (kilograms per capita/year) and the status of national bans.

RESULTS

Period MRs increased with statistical significance in five countries, with marginal significance in two countries, and were equivocal in 24 countries (five countries in Northern and Western Europe recorded negative APC values). Countries adopting asbestos bans reduced use rates about twice as fast as those not adopting bans. Turning points in use preceded bans. Change in asbestos use during 1970-1985 was a significant predictor of APC in mortality for pleural mesothelioma, with an adjusted R(2) value of 0.47 (p < 0.0001).

CONCLUSIONS

The observed disparities in global mesothelioma trends likely relate to country-to-country disparities in asbestos use trends.

Lung function predicts survival in a cohort of asbestos cement workers

PURPOSE

To study the predictive power of respiratory screening examinations a cohort of asbestos workers was followed from active work in an asbestos cement plant until death.

METHODS

From a cohort with data on individual exposure since first employment 309 workers who had a preventive medical examination in 1989/1990 were observed until death or the end of 2006. The impact of asbestos exposure (fibre years) and of smoking history on lung function was examined by linear regression, on specific causes of death and total mortality by Cox regression. The prognostic value of lung function, chest X-ray, and various clinical findings regarding total mortality was also examined by Cox regression.

RESULTS

Lung function proved to be the best predictor of survival apart from current smoking. Depending on the lung function variable an impairment by the interquartile range resulted in a hazard ratio of 1.5-1.6 while for current smokers it was 2.3. An increase of 70 fibre years (interquartile range) led to a hazard ratio of only 1.1. Lung function was influenced by asbestos exposure, current (but not former) smoking, and by pathological X-ray findings. The risk for pleural mesothelioma was dominated by time since first exposure to crocydolite in the pipe factory while the risk for bronchial cancer increased with smoking and total fibre years. An unexpected finding was an increase of gastric cancer in asbestos cement workers.

CONCLUSION

Lung function decrease predicts risk of premature death better than exposure history and regular spirometry should therefore be offered as primary screening to all former asbestos workers. In workers with a history of high cumulative exposure or rapid lung function decrease or radiological signs (diffuse pleural thickening or small irregular opacities) more sensitive techniques (high resolution computer tomography) need to be applied. All smokers with a history of asbestos exposure should be given free smoking cessation therapy to prevent premature death and lung cancer in particular.

[Malignant pleural mesothelioma: interrogations and hopes concerning the expected epidemic]

Malignant pleural mesothelioma (MPM) is a rare incurable tumor. Interest in MPM has increased in recent years due to a steadily increasing incidence subsequent to the intensive use of asbestosis, the main causal agent, but also due to better awareness in the political and scientific communities faced with a serious public health issue. Our knowledge of MPM has improved regularly in terms of pathologic diagnosis and the mechanisms underlying the mesothelial carcinogenesis. MPM is also the subject of many technological innovations as illustrated by the recent identification of new biological markers, access to metabolic imaging, and clinical research on targeted treatments. Proper management implies the participation of the general population since the implementation of administrative procedures for social indemnities. In 2007, a more aggressive therapeutic approach is becoming common practice with the use of radiotherapy and the emergence of the concept of multimodal care centered on wide pleuropneumonectomy. These advances create real hope for improvement, but also many interrogations since no standard treatment protocol has been clearly identified.