Recently learned that oral infection with some strains of HPV may be a much greater risk for throat cancer than smoking and drinking:http://www.newscientist.com/article/dn11819-oral-sex-can-cause-throat-cancer.html
(from the article)After controlling for other risk factors for throat cancer, such as drinking and smoking, the analysis revealed that people who had prior infection with HPV were 32 times as likely to have this cancer as those with no evidence of ever having the virus. And those who tested positive for a particularly aggressive strain of the virus, called HPV-16, were 58 times more likely to have throat cancer.
By comparison, either smoking or drinking increases the risk of such cancer by about threefold.
It's concerning when you think about the burgeoning rates of oral HPV infection. Anyway, the more you know...