What is the movie about the Iditarod where the dog owner has health issues and the dog dies at the end?

No, it's not Balto.. No, it's not Snow Dogs.. It's not Disney as far as I remember. I watched it in 3rd grade (11 years ago) relatively sure the dog dies at the end. That or the owner does. Not even 100% sure it's a movie involving the Iditarod per se, but it most definitely has sled dogs in it.