Keratins (K8 and K19) as potential markers of recurrent basal cell carcinoma

The keratin phenotype of 10 cases of recurrent basal cell carcinoma was assayed immunohistochemically using a panel of monospecific monoclonal antibodies to keratins and compared with the keratin phenotype of 10 primary (untreated), nodular basal cell carcinomas. The two groups showed identical expression patterns for K5, K14 and K17. However, K8 and/or K19 were found in 9 of the recurrent basal cell carcinomas, while only 2 primary basal cell carcinoma expressed these keratins. These findings suggest that the expression of simple epithelial keratins may be of biological importance in basal cell carcinomas and could be related to tumour invasion and/or changes in epithelial-mesenchymal interactions.