Black (air-cured) and blond (flue-cured) tobacco and cancer risk III: Oesophageal cancer

Relative risks of oesophageal cancer for smoking were higher in communities smoking mainly black tobacco, when compared with results from populations comprising mainly users of blond tobacco. Also, hand-rolled cigarette smoking, which could be considered as a proxy indicator of black tobacco smoking, was also associated with higher risk of oesophageal cancer, in comparison with the use of commercial (manufactured) cigarettes. Finally, the use of pipes and cigars showed odds ratios of higher magnitude than those associated with cigarettes. This indirect evidence of a higher risk of oesophageal cancer due to the use of black products was confirmed in three recent hospital-based case-control studies. These investigations were able to compare the effect of both types of tobacco; relative risks for black tobacco were two to three times higher than risks associated with blond tobacco smoking, after controlling for major potential confounders. Laboratory evidence suggests that swallowing tobacco condensates could be a major risk factor for oesophageal cancer. Also, the higher content of tobacco-specific N -nitroso compounds in black tobacco, including organospecific substances, could explain its higher carcinogenic effect on the oesophageal mucosa.