Immunohistochemical Evaluation of Expression of CK19 Premalignant Indicator in Oral Lichenoid Reaction (OLR) Compared to Oral Lichen Planus (OLP), Oral Squamous Cell Carcinoma (OSCC) and Normal Oral Mucosa

OLP is a relatively common chronic inflammatory skin disease with an immunologic background that often affects the oral mucosa. OLR is a mucosal lesion, clinically and histologically similar to OLP, and can occur in the oral cavity in response to some drugs or synthetic materials. The risk of dysplastic changes have been considered in both lesions. On the other hand, OSCC is one of the most common malignancies of the oral cavity. The aim of this study was to evaluate and compare expression of cytokeratin-19 (CK19) in OLP, OLR, OSCC and normal oral mucosa in terms of their staining intensity and patterns.
This descriptive-retrospective analysis was performed on 70 samples obtained from paraffin blocks of 20 cases of OLP, 20 cases of OLR, 20 cases of OSCC and 10 samples of normal oral mucosa. CK19 expression pattern and intensity of immunohistochemical staining were evaluated using Envision method. Data were analyzed with SPSS 20 using two-tailed regression test.
There seemed to be a significant relationship between suprabasal expression of CK19 and type of lesion (p value Increased expression of CK19 was dramatically consistent with region (basal and suprabasal) and type of lesion. In addition, the pattern of expression of CK19 in OLR and OSCC was very similar. Therefore, perhaps this protein marker might be used as both a diagnostic tool to distinguish lichen planus from lichenoid lesions and as a detector in possible malignant transformation of lichenoid lesions.