Stomach, Forestomach - Hyperkeratosis

comment:
Hyperkeratosis is defined as thickening of the stratum corneum. It occurs in two forms: orthokeratotic or parakeratotic hyperkeratosis. In orthokeratotic hyperkeratosis (also referred to as orthokeratosis squamous epithelial cells are anuclear, whereas in parakeratotic hyperkeratosis (also referred to as parakeratosis) the squamous epithelial cells have retained pyknotic nuclei. Hyperkeratosis frequently accompanies hyperplasia ( Figure 1

recommendation:
If hyperkeratosis is present without epithelial hyperplasia, then the hyperkeratosis should be diagnosed and graded. The severity grade should be based on the thickness of the keratin layer and the amount of surface area involved. If the hyperkeratosis accompanies epithelial hyperplasia, the hyperkeratosis is not diagnosed separately unless it is a prominent component of the lesion. If the hyperkeratosis is not diagnosed separately, it should be described in the pathology narrative. Hyperkeratosis is not subdivided into orthokeratosis or parakeratosis in the diagnosis, but the lesion should be well described in the narrative.references:
Frantz JD, Betton GR, Cartwright ME, Crissman JW, Macklin AW, Maronpot RR. 1991. Proliferative lesions of the non-glandular and glandular stomach in rats. GI-3. In Guides for Toxicologic Pathology. STP/ARP/AFIP, Washington, DC, 1-20. Full Text: https://www.toxpath.org/docs/SSNDC/StomachProliferativeRat.pdf
Hargis AM, Ginn PE. 2007. The integument. In: Pathologic Basis of Veterinary Disease, 4th ed (McGavin MD, Zachary JF, ed). Mosby, St Louis, MO, 1107-1261.
National Toxicology Program. 1996. NTP TR-383. Toxicology and Carcinogenesis Studies of 1-Amino-2,4-dibromoanthraquinone (CAS No. 81-49-2) in F344/N Rats and B6C3F1 Mice (Feed Studies). NTP, Research Triangle Park, NC. Abstract: https://ntp.niehs.nih.gov/go/11305
Web page last updated on: November 25, 2014