CK20 Gastrointestinal Marker Test - Immunohistochemistry: Cytokeratin 20 (CK20)

Immunohistochemistry for Cytokeratin 20 (CK20) aims to detect this specific low molecular weight keratin type. CK20 is normally expressed in the epithelial cells of the gastrointestinal tract (from stomach to rectum), transitional epithelium of the bladder, and Merkel cells of the skin. Its expression pattern, especially in conjunction with CK7, is a powerful diagnostic tool in determining the origin of metastatic carcinoma.