What is the relationship of smokeless tobacco and oral cancer?

Very high: Tobacco juice and smoke contains carcinogens that cause normal cells to change into cancer cells. There is a significant link between cancer of the lip, mouth, tongue and throat with the use of smokeless tobacco products. This link between smokeless tobacco and oral cancer is beyond question.

Causative : Smokeless tobacco causes oral cancer. Plain and simple. Not everyone who uses smokeless tobacco will get it but the likelyhood of someone using smokeless tobacco getting cancer is huge compared to someone who doesn't use it.