Worldwide, oral cancer represents approximately 5 per cent of all malignant lesions, with over 800 new intra-oral squamous cell carcinomas registered in Australia each year (average number of new cancers for tongue and mouth cancer between 1999 to 2003 was 881 per year; http://www.aihw.gov.au/publications/can/ca06/ca06-c02.pdf). Despite recent advances in therapy, the five-year survival rate remains around 50 per cent and the sequelae of treatment can be seriously debilitating. Cancer evolves in a series of distinct steps, each characterized by the sequential accumulation of additional genetic defects followed by clonal expansion.1 It has been long established that smoking, alcohol consumption, as well as tobacco chewing are risk factors linked to the development of oral cancer.2 Other suspected aetiological factors include viruses such as human papilloma virus and epstein barr virus, as well as Candida albicans,3 areca (betel nut) chewing, diets low in carotenoids and vitamin A4 and several measures of poor oral hygiene, including frequency of tooth brush use.5
