Incidence of pleural mesothelioma in a community exposed to fibres with fluoro-edenitic composition in Biancavilla (Sicily, Italy)

GOECP/SEOR clinical guidelines on radiotherapy for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare tumor with poor prognosis and rising incidence. Palliative care is common in MPM as radical treatment with curative intent is often not possible due to metastasis or extensive locoregional involvement. Numerous therapeutic advances have been made in recent years, including the use of less aggressive surgical techniques associated with lower morbidity and mortality (e.g., pleurectomy/decortication), technological advancements in the field of radiotherapy (intensity-modulated radiotherapy, image-guided radiotherapy, stereotactic body radiotherapy, proton therapy), and developments in systemic therapies (chemotherapy and immunotherapy). These improvements have had as yet only a modest effect on local control and survival. Advances in the management of MPM and standardization of care are hampered by the evidence to date, limited by high heterogeneity among studies and small sample sizes. In this clinical guideline prepared by the oncological group for the study of lung cancer of the Spanish Society of Radiation Oncology, we review clinical, histologic, and therapeutic aspects of MPM, with a particular focus on all aspects relating to radiotherapy, including the current evidence base, associations with chemotherapy and surgery, treatment volumes and planning, technological advances, and reradiation.

Overexpression of microRNA‑486 affects the proliferation and chemosensitivity of mesothelioma cell lines by targeting PIM1

Dysregulated levels of microRNAs (miRNAs or miRs), involved in oncogenic pathways, have been proposed to contribute to the aggressiveness of malignant pleural mesothelioma (MPM). Previous studies have highlighted the downregulation of miRNA miR-486-5p in patients with mesothelioma and the introduction of miRNA mimics to restore their reduced or absent functionality in cancer cells is considered an important therapeutic strategy. The aim of the present study was to evaluate the mechanisms through which miRNAs may influence the functions, proliferation and sensitivity to cisplatin of MPM cells. In the present study, a miR-486-5p mimic was transfected into the H2052 and H28 MPM cell lines, and cell viability, proliferation, apoptosis and mitochondrial membrane potential were monitored. miR-486-5p overexpression led to a clear impairment of cell proliferation, targeting CDK4 and attenuating cell cycle progression. In addition, transfection with miR-486-5p mimic negatively regulated the release of inflammatory factors and the expression of Provirus integration site for Moloney murine leukaemia virus 1 (PIM1). The sensitivity of the cells to cisplatin was enhanced by enhancing the apoptotic effects of the drug and impairing mitochondrial function. On the whole, the present study demonstrates that miR-486-5p may play an important role in MPM treatment by targeting multiple pathways involved in tumour development and progression. These activities may be mostly related to the downregulation of PIM1, a crucial regulator of cell survival and proliferation. Furthermore, these results provide support for the combined use of miR-486-5p with chemotherapy as a therapeutic strategy for MPM.

ERS/ESTS/EACTS/ESTRO guidelines for the management of malignant pleural mesothelioma

The European Respiratory Society (ERS)/European Society of Thoracic Surgeons (ESTS)/European Association for Cardio-Thoracic Surgery (EACTS)/European Society for Radiotherapy and Oncology (ESTRO) task force brought together experts to update previous 2009 ERS/ESTS guidelines on management of malignant pleural mesothelioma (MPM), a rare cancer with globally poor outcome, after a systematic review of the 2009-2018 literature. The evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach. The evidence syntheses were discussed and recommendations formulated by this multidisciplinary group of experts. Diagnosis: pleural biopsies remain the gold standard to confirm the diagnosis, usually obtained by thoracoscopy but occasionally via image-guided percutaneous needle biopsy in cases of pleural symphysis or poor performance status. Pathology: standard staining procedures are insufficient in ∼10% of cases, justifying the use of specific markers, including BAP-1 and CDKN2A (p16) for the separation of atypical mesothelial proliferation from MPM. Staging: in the absence of a uniform, robust and validated staging system, we advise using the most recent 2016 8th TNM (tumour, node, metastasis) classification, with an algorithm for pre-therapeutic assessment. Monitoring: patient's performance status, histological subtype and tumour volume are the main prognostic factors of clinical importance in routine MPM management. Other potential parameters should be recorded at baseline and reported in clinical trials. Treatment: (chemo)therapy has limited efficacy in MPM patients and only selected patients are candidates for radical surgery. New promising targeted therapies, immunotherapies and strategies have been reviewed. Because of limited data on the best combination treatment, we emphasise that patients who are considered candidates for a multimodal approach, including radical surgery, should be treated as part of clinical trials in MPM-dedicated centres.

A Comparison of Environmental Concerns in Two Disparate Montana and Nevada Communities

Asbestos refers to six fibrous minerals that occur naturally in the environment in the United States and throughout the world. Deposits may be found in soil, rocks, and deposits of other minerals such as vermiculite and talc. These naturally occurring asbestos (NOA) minerals belong to the serpentine and amphibole family of minerals. This chapter reports shared components of community-driven environmental concerns related to exposure to NOA in a rural Montana and a suburban Nevada community. The specific aim is to establish an understanding of the community and community member's primary concern(s) related to NOA in both communities. The knowledge that NOA is commonly found in areas across the United States supports the need for additional research into the health effects of environmental exposure and best-practices to reduce exposure risk while allowing communities to thrive economically.

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.

Asbestos Ban in Italy: A Major Milestone, Not the Final Cut

Background and history: Italy was the main asbestos producer and one of the greatest consumers in 20th century Europe until the asbestos ban was introduced in 1992. Asbestos exposure affected the population in a wide range of working environments, namely mining and marketing of asbestos, asbestos cement production, shipyards and textile industries. This also determined a widespread environmental asbestos exposure affecting the surrounding communities. Methods: To investigate the drivers and difficulties of the process leading to the asbestos ban and its subsequent implementation, we focused on stakeholder involvement, environmental health policies, capacity building and communication. Results: In the past three decades, stakeholder involvement has been instrumental in advancing the industrial asbestos replacement process, prevention and remediation interventions. Furthermore, involvement also contributed to the integration of environmental and health policies at national, regional and local levels, including capacity building and communication. In a global public health perspective, international scientific cooperation has been established with countries using and producing asbestos. Discussion and Conclusions: Key factors and lessons learnt in Italy from both successful and ineffective asbestos policies are described to support the relevant stakeholders in countries still using asbestos contributing to the termination of its use.

Environmental asbestos exposure and risk of mesothelioma

Mesothelioma is commonly considered an occupational disease occurring as a result of asbestos exposure in the workplace. Several avenues for environmental asbestos exposures have been described and may be associated with asbestos related disease, including mesothelioma. Worker take-home asbestos, or para-occupational exposure, has been well documented and is the most commonly reported pathway for asbestos exposure among mesothelioma cases that do not have history of occupational asbestos exposure. Observational studies have evaluated several communities with elevated mesothelioma incidence and environmental exposures attributed to local asbestos-related industries. Potential, but uncertain, mesothelioma risk also may be associated with general population asbestos exposure through contact with asbestos-containing commercial products, particularly housing materials that can be easily disturbed through normal activity. Finally, studies have described elevated mesothelioma incidence in several areas where populations are exposed to naturally occurring asbestos materials. These various environmental asbestos exposure pathways are poorly understood, and further studies should be pursued to evaluate their respective importance for population mesothelioma risk.

Fluoro-edenite and carbon nanotubes: The health impact of 'asbestos-like' fibres

Several decades have passed since Wagner et al demonstrated a causal link between asbestos fibre inhalation and the development of pleural mesothelioma in 1960. It was later suggested that pleural plaques are a benign consequence of exposure to these fibres. Most recently, a significant association between exposure to asbestos and cancer diagnosed at various sites, such as the peritoneum, stomach, pharynx, colon and ovaries has been demonstrated. The great concerns about public health that arose from the scientific evidence presented above have led to the banning of asbestos in several countries. Over the years, the suspicion that particles with a high aspect ratio may have asbestos-like pathogenicity has been supported by increasing evidence. Natural occurring minerals, as well as man-made fibres, have proven capable of inducing either chronic inflammation of serous membranes, or, in some cases, the development of peritoneal and pleural mesothelioma. The pathogenic role of both fluoro-edenite and carbon nanotubes, two ‘asbestos-like’ fibres is summarized and discussed in this review. The data presented herein support the notion that occupational exposure to these two types of fibre contributes to the development of different types of cancer.