Cytokeratin 10 (EP97)

Cytokeratin 10 (CK10) belongs to type I and acidic keratin family.1 It is low molecular weight keratin that is usually expressed in suprabasal keratinocytes and can also be seen in suprabasal cells of internal noncornifying, stratified squamous epithelia.1 In addition, CK10 is reported to be a typical component of cells of eccrine sweat gland ducts and sebaceous cells.2 Anti-CK10 is helpful in the identification of well differentiated squamous cell carcinoma derived from skin or from internal organs.2,3 However, CK10 was found to be sparse in poorly differentiated squamous cell carcinoma, even though it has been reported that focal CK10 expression has been found in 50% of cases of oral and pharyngeal squamous cell carcinoma.3 Anti-CK10 has demonstrated utility in the differentiation of extra-mammary Paget’s disease (negative) from basal cell carcinoma and squamous cell carcinoma (positive).3