Fig. 9.25 In these examples of high-grade squamous intraepithelial lesion (HSIL) involving endocervical glands, features can mimic many of the
criteria of endocervical glandular lesions. (A, B) Densely packed hyperchromatic crowded groups with prominent nucleoli, which is not a classic squamous
dysplasia characteristic. (C) A group of cells "streaming” in one polar direction. Classic HSIL generally lacks polarity. (D) Nuclei and cytoplasm extending from the
edge of a group in manner reminiscent of feathering (liquid-based preparations, Papanicolaou x (A, B, D) MP, (C) HP).
Fig. 9.26 A hyperchromatic crowded group showing both feathered edges and nucleoli from a case of HSIL involving an endocervical gland. Lack of
rosettes and well-defined strips of cells should alert the observer to the possibility of a more common squamous dysplasia origin. Background isolated HSIL
cells should always be sought when groups suspicious for HSIL are found. When such cells (B) are found, a squamous "cause" is always most likely (liquid-based
preparations, Papanicolaou x (A) MP, (B) HP).