Xu ES, et al. - The diverse and unique expression patterns of cytokeratin 13 (CK13) and cytokeratin 17 (CK17) were evaluated. The role of CK17 as a predictor for head and neck squamous cell carcinoma (HNSCC) metastasis and prognosis was also investigated. In non-cancerous tissues, CK13 was predominately expressed and was lost in HNSCC. CK17 under-expression is a potential predictor of nodal metastasis and adverse prognosis.