Ha! I'd give it right back to the crazy bitch.
I'd explain to her that tofu is GMO, and that's that's probably upping her cancer risk.
I'd tell her that they've found white rice to be less toxic than brown rice, because rice (even organic rice) often has a lot of arsenic in it and they have found that white rice is safer because it loses a lot of the junk in the processing.
I'd ask her if she's been tested for heavy metals after all that brown rice.
I'd grill her about her supplementing regime, too.
Is she getting enough vitamin D? Man! If she had been getting her levels tested regularly in the years leading up to her diagnosis, perhaps she could have avoided cancer!
I'd print out a lot of information about the dangers of gluten, and I'd ask her why she feels it's safe.