CK20 and CK5/6 Immunohistochemical Staining of Urothelial Neoplasms: A Perspective

Figure 7

(a) Urothelial carcinoma in situ with strong full-thickness immunostaining for CK20 with a distinct basal cell layer positive for CK5/6. (b) Another urothelial carcinoma in situ featuring strong staining for CK20 and absence of basal layer. (c) Pagetoid extension of urothelial carcinoma demonstrated by strong cytoplasmic staining for CK20 in a background of multiple layers of basal cells reactive for CK5/6.

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(b)

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