Reproductive System, Female
Ovary - Cyst, Epithelial
Narrative
Epithelial cysts (Figure 1 and Figure 2) are seen occasionally in mice and are rarely seen in rats. These cysts are considered to arise from downgrowth of the surface epithelium of the ovary. The cysts are lined by flattened, cuboidal, columnar, or squamous epithelium; squamous epithelium may be keratinized. The lining epithelium may resemble that of the surface epithelium.
Ovarian epithelial cysts should be diagnosed, but cysts occurring as background lesions need not be graded. In the case of an epithelial cyst, the diagnosis should include the type of cyst as a modifier (i.e., Ovary - Cyst, Epithelial). If the cysts are thought to be treatment related, they may be graded to fully characterize the treatment effect. If applicable, the terms "bilateral" and "multiple" may be included in the diagnosis.
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Full Text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4253081/Faccini JM, Abbott DP, Paulus GJJ. 1990. Female genital tract. In: Mouse Histopathology: A Glossary for Use in Toxicity and Carcinogenicity Studies (Greaves P, Faccini JM, eds). Elsevier, Amsterdam, 147-168.
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Abstract: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1474552/National Toxicology Program. 1995. NTP TR-438. Toxicology and Carcinogenesis Studies of Benzethonium Chloride (CAS No. 121-54-0) in F344/N Rats and B6C3F1 Mice (Dermal Studies). NTP, Research Triangle Park, NC.
Abstract: https://ntp.niehs.nih.gov/go/6020
Ovary - Cyst, Epithelial in a female B6C3F1/N mouse from a chronic study. The cyst is compressing adjacent ovarian parenchyma.
All Images
Ovary - Cyst, Epithelial in a female B6C3F1/N mouse from a chronic study. The cyst is compressing adjacent ovarian parenchyma.
Ovary - Cyst, Epithelial in a female B6C3F1/N mouse from a chronic study (higher magnification of Figure 1). Two adjacent epithelial cysts are lined by stratified squamous epithelium and contain keratin.