Introduction: Oral squamous cell carcinoma (OSCC) is the 3 rd most pervasive malignancy in India. The indicative of oral malignancy is the mechanism of invasion and metastasis, which is facilitated by numerous enzyme systems, chiefly matrix metalloproteinases (MMPs). Among them, MMP-9 performs a major role in the facilitation of these processes by its ability to degrade the basal lamina and extracellular matrix. Oral carcinomas can develop from the progression of premalignant oral conditions. The early tissue changes occurring in oral potentially malignant disorders (OPMDs) lead to cellular alteration with expression of MMP-9, indicating that these MMPs influence the disease process. Materials and Methods: This retrospective cross-sectional study included five study groups comprising histopathologically diagnosed cases of oral lichen planus (10 cases), oral submucous fibrosis (10 cases), oral leukoplakia (10 cases), OSCC (10 cases), and normal oral mucosa (10 cases). Results: After evaluation and comparison of the area and intensity of staining of MMP-9 among the groups, it is significantly appreciated in OSCC (100% positive expression) and OPMD disorders when compared to the mucosa free of lesions. Conclusion: MMP-9 can be considered a reliable marker to assess invasion and prognosis in OSCC. The expression of MMP-9 in OPMDs suggests alteration in the epithelial cells, thereby prompting early management to curb lesion carcinogenesis.
Velmurugan et al. (Thu,) studied this question.