Epithelial-mesenchymal transition is a process that describes the development of motile. Recent studies indicate that the phenomenon of Epithelial-mesenchymal transition plays a key role in carcinoma aggressiveness. This book evaluates, compares and correlates the immunohistochemical expression of _-cat, MMP1, FN, SNAI1, &TWIST2 as an epithelial-mesenchymal transition markers with tumor depth, pattern of invasion, eosinophilia, mitosis, and inflammatory cell intensity in oral squamous cell carcinoma.