Cytokeratin20 (CK20)

CK20 is a low molecular weight keratin with a molecular weight of 46KDa. CK20 is mainly expressed in the gastrointestinal epithelium, urothelium and Merkel cells. It can be used for the differential diagnosis of small cell carcinomas. The combined expression of CK7 and CK20 can be used to determine the primary site of cancer.