I am on a German Shepherd site and there are so many posts about cancer killing dogs between 6 and 9 years old, in some cases younger.
Back in the 60s and early 70s, friends and family fed only Strongheart canned dogfood and they could live over 15. It would be interesting to see the ingredients in that food compared to the food they have now. I am still searching to see if I find anything on it.