Lung - Metaplasia, Osseous

Lung - Metaplasia, Osseous in a F344/N rat from a chronic study. A focus of unmineralized bone is present in the lung parenchyma.
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Lung - Metaplasia, Osseous in a F344/N rat from a chronic study (higher magnification of Figure 1). The eosinophilic material in the lung is unmineralized bone.
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Lung - Metaplasia, Osseous in a male F344/N rat from a subchronic study. A focus of mineralized bone is present in the lung parenchyma.
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Lung - Metaplasia, Osseous in a female B6C3F1/N mouse from a chronic study. There is a subpleural focus of mineralized bone within a focus of unmineralized bone.
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Lung - Metaplasia, Osseous from a male Wistar Han rat in a chronic study. Though this focus of osseous metaplasia (arrow) is within an area of inflammation, it is likely not treatment related.
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comment:
Osseous metaplasia ( Figure 1






recommendation:
Lung - Metaplasia, Osseous is generally considered a background lesion but should be diagnosed for completeness. Similarly, cartilaginous metaplasia should also be diagnosed when present. These lesions need not be graded.references:
Dixon D, Herbert RA, Sills RC, Boorman GA. 1999. Lungs, pleura, and mediastinum. In: Pathology of the Mouse: Reference and Atlas (Maronpot RR, Boorman GA, Gaul BW, eds). Cache River Press, Vienna, IL, 293-332.
Long PH, Leininger JR, Nold JB, Lieuallen WG. 1993. Proliferative lesions of bone, cartilage, tooth, and synovium in rats. MST-2. In: Guides for Toxicologic Pathology. STP/ARP/AFIP, Washington, DC.
Web page last updated on: December 03, 2015