Risk assessment of tobacco types and oral cancer.

Problem statement: Oral cancer is one of the most common life threatening cancers all over the world, in particular Asian countries and tobacco is considered to be the most potent risk factor for oral cancer. This study was conducted to investigate the risk factors for oral cancer among the subjects from the studied area. Approach: A case-control study of 350 cases and 350 controls over a period of 19 months during April 2005 and September 2006 was carried out. The self reported information about their tobacco, alcohol along with other associated habits was collected by structured questionnaires. The consumption of tobacco was classified into three types, active smoking, passive smoking and smokeless form of tobacco. Results: There was a significant association between consumption of tobacco and the development of oral cancer (p<0.05 for all). Active smoking, in particular bidi smoking showed strong association with oral cancer compared to the passive smoking. Of the smokeless tobacco type, gutkha and tobacco flakes consumption showed the strong association. However, betel leaf and paan parag chewing had no association. While, alcohol consumption was associated with oral cancer with strongest determinant being the consumption of hard liquor. Dietary habits, in particular the non-vegetarian diet was significantly associated with oral cancer. The entire associations were statistically adjusted for possible confounders like age, gender, alcohol, the use of other tobacco types, non-vegetarian diet, education, location and monthly household income as appropriate. Conclusion: Smokeless tobacco consumption emerged as the strongest risk factor for oral cancer.