Assessment and clinicopathological correlation of matrix metalloproteinase 9 expression in nasopharyngeal carcinoma.

Introduction: Nasopharyngeal cancer is not a common disease in most parts of the world. In India also, nasopharyngeal carcinoma (NPC) is not a common cancer, except for the Northeastern region of the country. Expression of matrix metalloproteinase 9 (MMP9) in the tumor cells is related to tumor invasion and metastasis.