Asbestos in extrapulmonary sites: omentum and mesentery.

Study Objectives: Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers.
Design: Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy.
Results: Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and ferruginous body burden. An increased total ferruginous body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p < 0. 05).
Conclusion: Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue.