Chronic rhinosinusitis (CRS) increases the risk of developing nasopharyngeal carcinoma (NPC) while nasopharyngeal reflux is known to be one of the major aetiological factors of CRS. Bile acid (BA), the component of gastric duodenal contents, has been recognised as a carcinogen. | Bile acids at neutral and acidic pH induce apoptosis and gene cleavages in nasopharyngeal epithelial cells Implications in chromosome rearrangement