This is what I found:
The New England Journal of Medicine study concluded that people who had one to five oral-sex partners in their lifetime had approximately a doubled risk of throat cancer compared with those who never engaged in this activity and those with more than five oral-sex partners had a 250% increased risk. http://en.wikipedia.org/wiki/Auparashtika
http://www.cdc.gov/cancer/hpv/statistics/headneck.htm
I hope this helps. :)
