Cristiana Pascucci

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

In some population‐based studies, a shorter median survival was observed in peritoneal as compared with pleural, malignant mesothelioma, but in others, longer median survival times or higher proportions of long‐term survivors were reported. Statistical instability could have caused these differences. We analyzed survival in peritoneal mesothelioma in a large and unselected population‐based case series. Cases (338) 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 performed according to selected individual characteristics, including limited treatment information in a subset of 194 cases. The results were compared with those obtained in a parallel study on pleural mesothelioma cases. Epithelioid histotype, younger age at diagnosis and, to a lesser degree, gender (women), and being diagnosed in a hospital with a thoracic surgery unit positively and significantly affected survival. The effect of treatment was positive but not statistically significant. No trend in the risk of death according to calendar period of diagnosis was present. Peritoneal mesothelioma cases had shorter median survival time than pleural cases, but a larger proportion of long‐term survivors. Survival patterns after peritoneal and pleural mesothelioma differed markedly. Treatment was not associated with a statistically significant improvement in survival, but our study included cases first diagnosed before the introduction of the most recent therapeutic approaches. This provides a large historical comparison for future studies on survival trends at the population level.

Pleural malignant mesothelioma epidemic: incidence, modalities of asbestos exposure and occupations involved from the Italian National Register.

Due to the large scale use of asbestos (more than 3.5 million tons produced or imported until its definitive banning in 1992), a specific national surveillance system of mesothelioma incident cases is active in Italy, with direct and individual anamnestic etiological investigation. In the period between 1993 and 2004, a case‐list of 8,868 pleural MM was recorded by the Italian National Register (ReNaM) and the modalities of exposure to asbestos fibres have been investigated for 6,603 of them. Standardized incidence rates are 3.49 (per 100,000 inhabitants) for men and 1.25 for women, with a wide regional variability. Occupational asbestos exposure was in 69.3% of interviewed subjects (N = 4,577 cases), while 4.4% was due to cohabitation with someone (generally, the husband) occupationally exposed, 4.7% by environmental exposure from living near a contamination source and 1.6% during a leisure activity. In the male group, 81.5% of interviewed subjects exhibit an occupational exposure. In the exposed workers, the median year of first exposure was 1957, and mean latency was 43.7 years. The analysis of exposures by industrial sector focuses on a decreasing trend for those traditionally signaled as “at risk” (asbestos‐cement industry, shipbuilding and repair and railway carriages maintenance) and an increasing trend for the building construction sector. The systematic mesothelioma surveillance system is relevant for the prevention of the disease and for supporting an efficient compensation system. The existing experience on all‐too‐predictable asbestos effects should be transferred to developing countries where asbestos use is spreading.

Incidence of extrapleural malignant mesothelioma and asbestos exposure, from the Italian national register

Objectives The epidemiology of extrapleural malignant mesothelioma is rarely discussed and the risk of misdiagnosis and the very low incidence complicate the picture. This study presents data on extrapleural malignant mesothelioma from the Italian National Mesothelioma Register (ReNaM). Methods ReNaM works on a regional basis, searching for cases and interviewing subjects to investigate asbestos exposure. Classification and code criteria for certainty of diagnosis and exposure modalities are set by national guidelines. Between 1993 and 2004, 681 cases were collected. Incidence measures and exposure data refer to the ReNaM database. Age-standardised rates were estimated by the direct method using the Italian resident population in 2001. Correlations between the incidence of pleural and non-pleural malignant mesothelioma for the 103 Italian provinces were analysed. Results Standardised incidence rates (Italy, 2004, per million inhabitants) were 2.1 and 1.2 cases for the peritoneal site (in men and women, respectively), 0.2 cases for the tunica vaginalis testis, and 0.1 in the pericardial site, varying widely in different parts of the country. Mean age at diagnosis for all extrapleural malignant mesothelioma cases was 64.4 years and the men/women ratio was 1.57:1. Median latency was over 40 years for all extrapleural sites combined. The correlation between pleural and peritoneal mesothelioma was 0.71 (Pearsons r coefficient, p<0.001). Modalities of exposure to asbestos fibres were investigated for 392 cases. Conclusions The rarity of the disease, the low specificity of diagnosis and difficulties in identifying the modalities of asbestos exposure call for caution in discussing aetiological factors other than asbestos.

Malignant mesothelioma due to non-occupational asbestos exposure from the Italian national surveillance system (ReNaM): epidemiology and public health issues

Introduction Italy produced and imported a large amount of raw asbestos, up to the ban in 1992, with a peak in the period between 1976 and 1980 at about 160 000 tons/year. The National Register of Mesotheliomas (ReNaM, “Registro Nazionale dei Mesoteliomi” in Italian), a surveillance system of mesothelioma incidence, has been active since 2002, operating through a regional structure. Methods The Operating Regional Center (COR) actively researches cases and defines asbestos exposure on the basis of national guidelines. Diagnostic, demographic and exposure characteristics of non-occupationally exposed cases are analysed and described with respect to occupationally exposed cases. Results Standardised incidence rates for pleural mesothelioma in 2008 were 3.84 (per 100 000) for men and 1.45 for women, respectively. Among the 15 845 mesothelioma cases registered between 1993 and 2008, exposure to asbestos fibres was investigated for 12 065 individuals (76.1%), identifying 530 (4.4%) with familial exposure (they lived with an occupationally exposed cohabitant), 514 (4.3%) with environmental exposure to asbestos (they lived near sources of asbestos pollution and were never occupationally exposed) and 188 (1.6%) exposed through hobby-related or other leisure activities. Clusters of cases due to environmental exposure are mainly related to the presence of asbestos-cement industry plants (Casale Monferrato, Broni, Bari), to shipbuilding and repair activities (Monfalcone, Trieste, La Spezia, Genova) and soil contamination (Biancavilla in Sicily). Conclusions Asbestos pollution outside the workplace contributes significantly to the burden of asbestos-related diseases, suggesting the need to prevent exposures and to discuss how to deal with compensation rights for malignant mesothelioma cases induced by non-occupational exposure to asbestos.

Epidemiological patterns of asbestos exposure and spatial clusters of incident cases of malignant mesothelioma from the Italian national registry

BackgroundPrevious ecological spatial studies of malignant mesothelioma cases, mostly based on mortality data, lack reliable data on individual exposure to asbestos, thus failing to assess the contribution of different occupational and environmental sources in the determination of risk excess in specific areas. This study aims to identify territorial clusters of malignant mesothelioma through a Bayesian spatial analysis and to characterize them by the integrated use of asbestos exposure information retrieved from the Italian national mesothelioma registry (ReNaM).MethodsIn the period 1993 to 2008, 15,322 incident cases of all-site malignant mesothelioma were recorded and 11,852 occupational, residential and familial histories were obtained by individual interviews. Observed cases were assigned to the municipality of residence at the time of diagnosis and compared to those expected based on the age-specific rates of the respective geographical area. A spatial cluster analysis was performed for each area applying a Bayesian hierarchical model. Information about modalities and economic sectors of asbestos exposure was analyzed for each cluster.ResultsThirty-two clusters of malignant mesothelioma were identified and characterized using the exposure data. Asbestos cement manufacturing industries and shipbuilding and repair facilities represented the main sources of asbestos exposure, but a major contribution to asbestos exposure was also provided by sectors with no direct use of asbestos, such as non-asbestos textile industries, metal engineering and construction. A high proportion of cases with environmental exposure was found in clusters where asbestos cement plants were located or a natural source of asbestos (or asbestos-like) fibers was identifiable. Differences in type and sources of exposure can also explain the varying percentage of cases occurring in women among clusters.ConclusionsOur study demonstrates shared exposure patterns in territorial clusters of malignant mesothelioma due to single or multiple industrial sources, with major implications for public health policies, health surveillance, compensation procedures and site remediation programs.

The epidemiology of malignant mesothelioma in women: gender differences and modalities of asbestos exposure

Introduction The epidemiology of gender differences for mesothelioma incidence has been rarely discussed in national case lists. In Italy an epidemiological surveillance system (ReNaM) is working by the means of a national register. Methods Incident malignant mesothelioma (MM) cases in the period 1993 to 2012 were retrieved from ReNaM. Gender ratio by age class, period of diagnosis, diagnostic certainty, morphology and modalities of asbestos exposure has been analysed using exact tests for proportion. Economic activity sectors, jobs and territorial distribution of mesothelioma cases in women have been described and discussed. To perform international comparative analyses, the gender ratio of mesothelioma deaths was calculated by country from the WHO database and the correlation with the mortality rates estimated. Results In the period of study a case list of 21 463 MMs has been registered and the modalities of asbestos exposure have been investigated for 16 458 (76.7%) of them. The gender ratio (F/M) was 0.38 and 0.70 (0.14 and 0.30 for occupationally exposed subjects only) for pleural and peritoneal cases respectively. Occupational exposures for female MM cases occurred in the chemical and plastic industry, and mainly in the non-asbestos textile sector. Gender ratio proved to be inversely correlated with mortality rate among countries. Conclusions The consistent proportion of mesothelioma cases in women in Italy is mainly due to the relevant role of non-occupational asbestos exposures and the historical presence of the female workforce in several industrial settings. Enhancing the awareness of mesothelioma aetiology in women could support the effectiveness of welfare system and prevention policies.

[SENTIERI - Epidemiological study of residents in national priority contaminated sites: incidence of mesothelioma]

The purpose of the SENTIERI-ReNaM Project is to analyse the incidence of mesothelioma in Italian National Priority Contaminated Sites (NPCSs) in order to estimate the health impact of asbestos on resident populations, disentangling the role of occupational and environmental exposures. SENTIERI Project has provided the relevant information on geographic and demographic structure of NPCSs and on existing sources of contamination. The Italian National Mesothelioma Registry (ReNaM), that covers the whole country through its Regional Operational Centres (CORs), has made available the procedures for estimating the incidence of mesothelioma in NPCSs and for assessing occupational and environmental asbestos exposure of the individual cases. The synergy between these two epidemiological surveillance systems lay also the ground for communication programmes with the affected communities.BACKGROUND in Italy, National Priority Contaminated Sites (NPCSs) are defined as of concern for remediation; most of them are sites with a long-lasting industrial activity. OBJECTIVE the study aims to estimate the burden of disease from mesothelioma in NPCSs. DESIGN mesothelioma incidence in the period 2000-2011 was estimated for the populations residing in the 39 Italian NPCSs. Data were taken from the Italian National Mesothelioma Registry (ReNaM). NPCSs were ranked into risk groups (RGs) on the basis of the presence of the following asbestos-exposing activities: 1. asbestos-cement plants; 2. asbestos mines; 3. harbours with shipyards; 4. illegal dumping sites containing asbestos; 5. petrochemicals and/or refineries, and/or steel plants; 6. chemical plants and/or landfills without explicit mention of asbestos. For the population residing in each NPCS, crude rates per 100,000 per year and number of observed minus expected cases (Obs-Exp) by gender were computed. Expected cases were calculated using the age-class rates of a reference population (the geographical macroarea of every NPCS). For every RG, the meta-analytic estimate of the attributable proportion (AP), i.e., the proportion of cases attributable to the local context, was computed, being the AP for each NPCS expressed as (Obs-Exp/Obs) x100. RESULTS the total number of mesothelioma cases estimated in the considered period of 12 years is 2,741 (2,048 males, 693 females). The total number of Obs-Exp cases was 1,531 (1,178 in males, 353 in females). In males, crude rate ranges from 71.5 in the RG1 to 3.0 in RG4, while in females it ranges from 48.4 in RG1 to 0.6 in RG4. In males, AP in RGs from 1 to 3 is over 65%, in RG4 is 59%, in RG5 is 30%, in RG6 is -14%. AP in females gradually drops from 95% in RG1 to -64% in RG6. CONCLUSIONS the burden of mesothelioma in populations residing in NPCSs is high, with an AP gradient consistent with the a priori RG. This burden impacts on females in a different way: rates are lower than male ones; AP is similar to male ones in the RGs 1 and 3.

O32-4 Spatial analysis of mesothelioma incidence and tracing of past asbestos exposure in italy

Introduction Due to the strong causal association with asbestos fibres, the distribution of incident malignant mesothelioma (MM) cases over time and space likely reflect different kinds of asbestos exposures occurring in the past, as previously demonstrated in several studies. Starting from the data of a disease-specific national registry, namely the Italian mesothelioma registry (ReNaM), a geographic cluster analysis was integrated with information about exposure, either occupational or non occupational, in order to trace patterns of asbestos exposure in Italy. Methods A total of 15,322 incident cases of all-site MM, recorded by ReNaM in the period 1993 to 2008 were analysed, corresponding to 11,852 occupational, residential and familial histories reconstructed by interview. Observed cases were mapped based on the municipality of residence at diagnosis and age-specific rates of the area where municipality was located was used to calculate expected cases. A Bayesian hierarchical model was applied to identify municipality clusters and each cluster was characterised by type and source of asbestos exposure of cases. Results Thirty-two clusters of MM were mapped. Asbestos manufacturing industries and shipbuilding and repair facilities were the more common sources of asbestos exposure, but other activity sectors, such as non-asbestos textile, metal engineering and construction had a relevant contribution in some clusters. Environmental asbestos exposure was detected more frequently in clusters with an asbestos cement industry or a natural source of asbestos-like fibres. Differences by gender among clusters were attributable to environmental fraction but also to high female employment in selected activity sectors, such as textile industry. Discussion This study while indirectly confirming the role of specific natural or industrial sources of asbestos exposure for mesothelioma risk, highlights the great public health implications of spatial tracing of asbestos exposure for risk prevention, health surveillance and welfare policies.