Malignant peritoneal mesothelioma in a boar who lived in Calabria (Italy): Wild animal as sentinel system of human health

Our plain-English summary of Malignant peritoneal mesothelioma in a boar who lived in Calabria (Italy): Wild animal as sentinel system of human health, by E. Colombino, S. Capella, F. Casalinuovo, et al (The Science of the Total Environment, 2019).

The study

• Authors: E. Colombino, S. Capella, F. Casalinuovo, R. Racco, F. Pruiti, M. Volante, V. Di Marco Lo Presti, E. Belluso, M.T. Capucchio
• Journal: The Science of the Total Environment
• Published: 2019;683:267-274
• Cited by: 8 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Mesothelioma is a tumor of the serosal membranes described both in human and veterinary medicine. While in humans the relationship between mesothelioma and exposure to asbestos and some other asbestiform minerals is well known, in animals it is still difficult to establish. In this paper a case of malignant peritoneal mesothelioma probably related to asbestos exposure in a wild boar is described. At post-mortem evaluation the peritoneum, diaphragm and serosal surface of liver and kidneys showed isolated to coalescent multiple nodular lesions. Samples from diaphragm, liver and lung were collected to perform microbiological and histological investigations. To assess the presence of asbestos and/or other asbestiform minerals, SEM-EDS investigations were performed on organs and soil samples collected from the area where the wild boar lived. Microbiological investigations were negative for Mycobacterium species. Gross and histological examination were compatible with a biphasic mesothelioma, with nodules composed of epithelioid and sarcomatoid elements with high pleomorphism. Immunohistochemistry revealed only multifocal scattered positivity for WT-1 and D2-40. Asbestos fibres were detected in all samples (organs and soil) by SEM-EDS, demonstrating a potential relationship between the neoplasia and the exposure to naturally occurring asbestos (NOA). In conclusion, the results of the present study are further confirmation that wild animals, such as the boar, are suitable sentinels to indicate the risk of environmental exposure to asbestos for human populations.

Copyright © 2019 Elsevier B.V. All rights reserved.

In plain English

This case report describes one 3-year-old female wild boar killed during the hunting season in Caulonia, Calabria, Italy. At post-mortem examination, nodules from 2 mm to 3 cm across covered the peritoneum, the diaphragm, and the outer surfaces of the liver and kidneys. No lesions were found in the chest. Tests for Mycobacterium (tuberculosis) bacteria were negative. Under the microscope, the nodules were compatible with a biphasic (epithelioid and sarcomatoid) malignant peritoneal mesothelioma. Only two of the mesothelioma markers tested, WT-1 and D2-40, showed scattered positive staining. Electron microscopy found chrysotile/asbestiform antigorite fibres in the lung, liver and diaphragm nodules. It also found tremolite/actinolite asbestos in the lung, at 5320 fibres per gram of dry tissue. Chrysotile/asbestiform antigorite was found in 2 of 5 soil samples from the area, and fibrous amphiboles were not detected in soil. The authors noted that the boar's amphibole asbestos burden was below a level considered a sign of significant exposure in humans. The authors concluded that wild animals such as the boar are suitable sentinels for the risk of environmental asbestos exposure to human populations.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Case report of a single wild animal, with pathology, microbiology, immunohistochemistry, and electron-microscope (SEM-EDS) analysis of fibres in its tissues and in soil from where it lived
• Who was studied: One 3-year-old female wild boar weighing 70 kg, killed during the hunting season in Caulonia (Reggio Calabria, Calabria, Italy); the hunter reported no signs of sickness before death
• Exposure: Environmental (naturally occurring) asbestos and other mineral fibres in the area where the boar lived, an area with active/abandoned quarries; fibres were measured in the boar's lung, liver and diaphragmatic nodules and in 5 soil samples
• Main results:
  • Multiple nodules, 2 mm to 3 cm in diameter, were found on the peritoneum, the diaphragm surface, and the serosal surface of the liver and kidneys; no lesions were found in the thoracic cavity
  • Microbiological testing was negative for Mycobacterium species, ruling out tuberculosis
  • The nodules were made of mixed epithelioid and sarcomatoid cells, compatible with a biphasic malignant mesothelioma; the lungs showed no histological alterations
  • Immunohistochemistry showed only multifocal scattered positivity for WT-1 and D2-40
  • Stains for calretinin, cytokeratin 5, HBME-1 and CEA were negative; the first three were considered inconclusive because internal control cells were also negative
  • In the boar's lung, fibres per gram of dry tissue were: tremolite/actinolite asbestos 5320; chrysotile/asbestiform antigorite 15,960 total; hornblende 7980; Na-Ca amphiboles 2660; illite-smectite 5320
  • Only chrysotile/asbestiform antigorite fibres were found in the diaphragmatic nodules (7980 fibres per gram of dry tissue) and in the liver (17,318 total fibres per gram of dry tissue)
  • Of the 5 soil samples, chrysotile/asbestiform antigorite was found in 2; fibrous amphiboles (asbestos or non-asbestos classified) were not detected in soil
  • In both the boar's tissues and the soil, chrysotile/asbestiform antigorite was the predominant fibrous mineral
  • The authors noted that the boar's amphibole asbestos lung burden was below the level (1 × 10^5 fibres per gram dry weight) considered in humans an indicator of significant asbestos exposure
• The authors' conclusion: The authors concluded that their results further confirm that wild animals such as the boar are suitable sentinels for indicating the risk of environmental asbestos exposure to human populations
• Limitations the authors state:
  • The authors suggested that the negative calretinin, cytokeratin 5 and HBME-1 stains may reflect poor antigen preservation, because the tissues were frozen before fixation
  • The authors could not exclude that fibrous amphiboles were missed in the soil because of the detection limit of the SEM-EDS method
  • SEM-EDS cannot tell chrysotile from asbestiform antigorite, or tremolite asbestos from actinolite asbestos, in digested tissue, so each pair was reported as one group

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Peritoneal Mesothelioma, Mesothelioma, Asbestiform, Asbestos Exposure, Peritoneum, Diaphragm, Serosal Surface, Biphasic Mesothelioma.

Related studies

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• The use of wild animal models to detect evidence of environmental contamination by asbestos-like substance — R. Puleio, M.R. Schiavo, et al. (2013)
• Asbestos Burden in Lungs of Subjects Deceased From Mesothelioma Who Lived in Proximity to an Asbestos Factory: A Topographic Post-Mortem SEM-EDS Study — S.D. Visonà, M. Untalan, et al. (2025)
• Malignant mesothelioma due to non-occupational asbestos exposure from the Italian national surveillance system (ReNaM): epidemiology and public health issues — A. Marinaccio, A. Binazzi, et al. (2015)
• Ophiolitic outcrops, naturally occurring asbestos exposure and mortality risk from malignant mesothelioma in Calabria (Southern Italy) — A. Scarselli, A. Marinaccio, et al. (2021)
• Asbestiform minerals in ophiolitic rocks of Calabria (southern Italy) — A. Campopiano, A. Olori, et al. (2018)

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