I have been feeding our dogs Rice & Lamb and as some of you know our dog developed Digestive tract cancer. I am now wondering about Rice in our dogs diets (Blue Buffalo) since the whole arsenic discovery

Why would you think it is connected to rice?

I heard in the news that arsenic can be linked to certain types of cancer. Still if there are high concentrations of arsenic in rice, it does not makes sense to feed it to your dog everyday.
http://www.wired.com/wiredscience/2012/09/arsenic-and-rice-yes-again/?utm_medium=referral&utm_source=pulsenews