Evaluation of Cytokeratin 19 Expression in Oral Carcinogenesis

Oral squamous cell carcinoma (OSCC) accounts for over 90% of oral cancers. Cytokeratin 19 (CK19), produced by suprabasal epithelial cells, reflects alterations in cellular behavior and has been associated with premalignant changes in the oral epithelium. This study aimed to evaluate the expression of CK19 in OSCC and oral epithelial dysplasia (OED) and its potential role in oral carcinogenesis.

A total of 50 samples were analyzed, including 30 OSCC cases and 10 OED cases obtained from the archives of the Department of Pathology, as well as 10 normal oral mucosa samples collected from clinically healthy areas adjacent to mucocele lesions. CK19 expression was assessed using immunohistochemistry.

Positive immunoreactivity for CK19 was observed in 90% (27/30) of OSCC samples. CK19 expression in the OSCC group was significantly higher compared to the OED and normal mucosa groups. Among OSCC cases, grade III tumors exhibited stronger CK19 expression than grades I and II. Additionally, CK19 expression in grade II OSCC was higher than in the OED group.

The progressive increase in CK19 expression from normal mucosa to OED and OSCC supports its involvement in oral mucosal carcinogenesis. Moreover, higher CK19 expression correlated with increasing tumor grade and decreasing cellular differentiation, suggesting its potential value as a diagnostic and prognostic biomarker in OSCC.