囊肿Cyst · 肾上腺 · 内分泌系统 · NTP ntp-0070

Comment：
Adrenal cysts ( Figure 1 , Figure 2 , and Figure 3 ) are lined by cuboidal to ciliated columnar epithelium and may contain amorphous to flocculent, eosinophilic material. They may be located in the cortex or medulla and may cause variable distortion or compression of the adjacent tissue. These minor findings are more common in mice than in rats and are usually incidental, spontaneous changes of no clinical or toxicologic relevance. Cortical cysts must be distinguished from angiectasis (dilated vascular channels containing blood and lined by flat endothelial cells). Cortical cysts in rats must also be distinguished from cystic degeneration, a common lesion in certain rat strains, which features irregular, often large cavitated spaces filled with proteinaceous fluid but lack the epithelial lining of true cysts ( Figure 2 and Figure 3 ).

Recommendation：
Adrenal gland cysts should be diagnosed only if they occur with treatment-related increased incidences. In these cases, they should be diagnosed but not assigned of a severity grade. When diagnosed, an appropriate site modifier (i.e., cortex or medulla) should be included in the diagnosis to indicate the location of the cyst.