Nose, Olfactory Epithelium, Glands - Metaplasia
comment:Bowman's gland metaplasia ( Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , and Figure 7 ) is similar to metaplasia of olfactory epithelium (see Nose, Epithelium - Metaplasia, Squamous and Nose, Olfactory Epithelium - Metaplasia, Respiratory) but occurs in the epithelium lining the Bowman’s glands. In respiratory metaplasia, the normal Bowman’s gland epithelium is replaced by ciliated respiratory epithelium (there may be variable numbers of goblet cells). In squamous metaplasia, the epithelium is replaced by squamous epithelium. There may be mixed squamous and respiratory metaplasia in some cases, as well as the presence of hyperplasia, dilation, atrophy, and/or inflammation. Diagnoses should be based on the most prominent lesion(s) present.
recommendation:"Nose, Olfactory epithelium, Glands - Metaplasia" should be diagnosed whenever it is present in the absence of lesions to the overlying epithelium, when the type of metaplasia differs from that of the overlying epithelium (e.g., squamous in the overlying epithelium and respiratory in the glands), or if it appears to be overly severe or excessive. Otherwise, the metaplasia should be described in the pathology narrative as a component of the metaplasia of the overlying epithelium. The type of metaplastic epithelium present (respiratory or squamous) should be included in the diagnosis as a modifier. Glands associated with the olfactory epithelium are assumed to be Bowman's glands, so it is not necessary to specify "Bowman's" in the diagnosis. It should be assigned a severity grade based on the extent of the lesion.
related links:Nose, Epithelium - Metaplasia, Squamous
Nose, Olfactory Epithelium, Glands – Hyperplasia
Nose, Olfactory Epithelium - Metaplasia, Respiratory
Long PH, Herbert RA, Peckham JC, Grumbein SL, Shackelford CC, Abdo Kl. 2003. Morphology of nasal lesions in F344/N rats following chronic inhalation exposure to naphthalene vapors. Toxicol Pathol 31:655-664. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/14585734
Web page last updated on: February 23, 2015