Fig. 4

Histological findings of perianal Paget’s disease. a Paget’s cells with clear cytoplasm and large pleomorphic nuclei (hematoxylin-eosin; magnification × 20). b–d Positive immunohistochemical staining for cytokeratin (CK) 7 (b), CK20 (c), and caudal-related homeobox gene nuclear transcription factor (CDX) 2 (d), and negative for gross cystic disease fluid protein (GCDFP) 15 (e) (magnification × 20)