TNFSF4 and neoplasm: Evidence is there that nicotine and areca nut consumption can lead to chronic inflammation by increasing macrophages and lymphocytes at the site of the tumor as well as elevated C-reactive protein levels.28, 29, 30The role of OX40/OX40L is reported in development of chronic inflammation due to nicotine exposure.31There is no such study which has evaluated the expression of OX40/OX40L in relation to different habits and tumor site in OSCC.