Esophagus - Hyperplasia

Image of hyperplasia in the esophagus from a female B6C3F1 mouse in a chronic study
Esophagus, Epithelium - Hyperplasia in a female B6C3F1 mouse from a chronic study. There are rete peg-like structures and accompanying hyperkeratosis.
Figure 1 of 2
Image of hyperplasia in the esophagus from a female B6C3F1 mouse in a chronic study
Esophagus, Epithelium - Hyperplasia in a female B6C3F1 mouse from a chronic study (higher magnification of Figure 1). There are rete peg-like structures and accompanying hyperkeratosis.
Figure 2 of 2
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comment:

Hyperplasia of the mucosal epithelium is characterized by an increased number of epithelial cells and the absence of atypia. The epithelial cells may be of one or more epithelial cell types (basal, spinous, or granulosum). In severe cases, rete peg-like structures may extend into the submucosa ( Figure 1image opens in a pop-up window and Figure 2image opens in a pop-up window ). Hyperkeratosis (increased thickness of the stratum corneum) is often seen when hyperplasia of the mucosa is present. Hyperplasia of the squamous mucosa with hyperkeratosis has been reported in the esophagus of the rat following chronic high-dose administration of vehicles such as alcohol.

recommendation:

Epithelial hyperplasia should be diagnosed and graded based on the size of the area of esophagus affected and the thickness of the hyperplastic esophageal epithelium. Hyperkeratosis associated with hyperplasia is usually not diagnosed as a separate entity, although it may be mentioned in the narrative. When hyperkeratosis is present in the absence of hyperplasia or when the hyperkeratosis is extreme, it should be diagnosed and graded separately from the hyperplasia (see description of Esophagus - Hyperkeratosis).

references:

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Full Text: http://tpx.sagepub.com/content/23/3/356.full.pdf

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Reindel JF, Pilcher GD, Gough AW, Haskins JR, de la Iglesia FA. 1996. Recombinant human epidermal growth factor-1–48-induced structural changes in the digestive tract of cynomolgus monkeys (Macaca fascicularis). Toxicol Pathol 24:669-679.
Abstract: http://www.ncbi.nlm.nih.gov/pubmed/9082544

Vinter-Jensen L. 1999. Pharmacological effects of epidermal growth factor (EGF) with focus on the urinary and gastrointestinal tracts. APMIS Suppl 93:40-42.
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