Cytokeratin expression in oral cancer and its relationship to tumor differentiation.

Although cytokeratin expression is said to alter with the state of tumor differentiation, few studies appear to have confirmed this in fresh tissue biopsies from oral squamous cell carcinomas. Previous studies have been limited by the number of antibodies utilized, small sample size, or lack of information regarding tumor differentiation. A panel of 8 antikeratin antibodies (of which five recognised the simple epithelial keratins, 8, 18 and 19) were applied to fresh tissue biopsies from 24 oral cancer and 15 normal oral mucosal biopsies. A standard immunocytochemical technique was followed (Vectastain ABC method), with keratin expression graded on a 3 point scale. Our analysis indicated that simple epithelial keratins (K8, K18, K19) were not confined to the more poorly differentiated tumors. This may be relevant to tumor prognosis.