Cytokeratins in cervical dysplasia and neoplasia: a comparative study of immunohistochemical staining using monoclonal antibodies NCL-5D3, CAM 5.2, and PKK1.

The expression of low molecular weight cytokeratins (normally expressed only in simple epithelia) in intraepithelial neoplasia of grade CIN III or greater in cervical biopsies has recently been described by Bobrow et al. Our study of 127 cases confirms this finding and in addition we compare the use of three monoclonal antibodies, namely NCL-5D3, CAM 5.2, and PKK1, in demonstrating the phenomenon. Both NCL-5D3 and CAM 5.2 give consistently negative results for non-neoplastic stratified squamous epithelium, as well as CIN I and CIN II lesions, whilst staining about 30 per cent of CIN III biopsies and most carcinomas. PKK1, on the other hand, stained 50 per cent of non-neoplastic epithelia and thus did not serve as a marker of severe dysplasia. The possible implications of these observations are discussed.