epithelial nest

ker·a·tin pearl

a focus of central keratinization within concentric layers of abnormal squamous cells; seen in squamous cell carcinoma.

epithelial nest

(1) A nonspecific term for a circumscribed mass of epithelial (usually squamous) cells. 
(2) Keratin pearl, see there.
References in periodicals archive ?
There was prominent palisading of cells at the periphery of the epithelial nests, giving the lesion a "basaloid" appearance (Figure).
Ki-67 labeled less than 5% of nuclei within the epithelial nests, and nuclear p53 staining was seen in approximately 5% to 10% of tumor cells.
The possible pluripotential character of the embryonic epithelial nests and the transformation of respiratory to squamous epithelium have been proposed to explain the various types of epithelial lining.
There were areas in which epithelial nests were mainly composed of large clear or faintly granular cells, and peripheral palisading and reversed nuclear polarity were essentially absent (Figure 3).
The epithelial nests displayed focal acantholysis and lacked any significant cytologic atypia (Figure 2).
In the center of the epithelial nests were laminated layers and whorls of squames recognized as "wet keratin.