Establishment of field change by expression of cytokeratins 8/18, 19, and MMP-9 in an apparently normal oral mucosa adjacent to squamous cell carcinoma: A immunohistochemical study

BACKGROUND: Squamous cell carcinoma is the most frequent malignancy of the oral cavity. The survival rate of this malignancy has not improved from past two decades. The major factors responsible for this could be due to loco regional and distant metastatic spread. However, the other important prognostic factor is concomitant occurrence and recurrence of multiple primary carcinomas in the head and neck region, which is explained as the concept of field cancerization. The evidence to support the field change in normal mucosa of Oral squamous cell carcinoma (OSCC) through biological markers using immunohistochemistry has always been challenging. AIM: Hence, the aim of the present research is to identify changes in the expression of CK 8/18, 19, and MMP-9 to visualize field changes in the clinically normal mucosa adjacent to OSCC and compare with non neoplastic normal oral mucosa. MATERIALS AND METHODS: 20 cases of OSCC with radical resection specimens were included in the study. Lesional tissue and adjacent normal looking mucosa were taken during grossing. Ten cases of non-neoplastic normal oral mucosa are also included in the study. Markers such as CK 8/18, CK 19, and MMP-9 are used by the immunohistochemical method in this present study. RESULT AND CONCLUSION: The enhance expression of CK 8/18 (80%), CK 19 (70%), and MMP 9 (90%) in ANM was noted and furthermore in six ANM showing severe dysplasia with enhance expression of CK 8/18, CK 19, and MMP 9 in the apparently normal oral mucosa can suggest a field cancerization.