Brain - Epidermoid Cyst

Brain, cingulate cortex-incidental epidermoid cyst (arrowhead) in a male B6C3F1 mouse from a chronic study.
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Lumbar spinal cord�incidental epidermoid cyst (arrow) in a male Sprague-Dawley rat from a chronic T-62 study.
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Cortex, sub-leptomeningeal-incidental epidermoid cyst (arrow) in a male F344/N rat from a chronic study.
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comment:
Epidermoid cysts are benign hamartomatous structures, which, from their location and size, may interfere with normal neural functions but are usually clinically silent since the slow increase in size allows for adaptation and compensation by the nervous system to the presence of the space-occupying mass. In Figure 1
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recommendation:
Although epidermoid cysts are generally considered background lesions, they should be diagnosed in NTP studies along with the subsite. Epidermoid cysts do not need to be graded.references:
Iaconetta G, Carvalho GA, Vorkapic P, Samii M. 2001. Intracerebral epidermoid tumor: A case report and review of the literature. Surg Neurol 55:218-222. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/11358593
Krinke GJ, Kaufmann W, Mahrous AT, Schaetti P. 2000. Morphologic characterization of spontaneous nervous system tumors in mice and rats. Toxicol Pathol 28:178-192. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/10669006
Web page last updated on: January 07, 2014