Asbestos Fibers and Ferruginous Bodies Detected by VP-SEM/EDS in Colon Tissues of a Patient Affected by Colon-Rectum Cancer: A Case Study

Abstract

The aim of this work was to inspect the presence of asbestos fibers in colon tissue from a patient, with history of indirect exposure to asbestos and affected by colon cancer, who underwent surgery. Variable pressure scanning electron microscopy, coupled with energy dispersive spectroscopy (VP-SEM/EDS), was used for identification of inorganic fibers and for their morphological—chemical characterization. Fresh tissue samples from both, healthy area close to the neoplasia and from the neoplastic regions, were separately digested to eliminate the biological matrix. The precipitate was analyzed by VP-SEM/EDS, identifying in samples from healthy tissue asbestos bodies and small asbestos fibers, and in samples from neoplastic tissue long fibers of asbestos, free from covering. A quantification of the asbestos bodies and the free fibers in the two type of specimens is proposed. Moreover, to locate the fibers in the biological medium, histological sections from the colon of the same patient were also examined. Free asbestos fibers appeared concentrated in the tissue bridge between the healthy and the neoplastic areas. Immuno-histochemical investigation performed on the neoplasia seems to exclude a role of microsatellite instability in the carcinogenesis process, suggesting an influence of the fibers.