Bone Cancer In Dogs

my dog is having seizures (two in the last four hrs)and I’m pretty sure it’s a brain tumor. he’s 11 yrs old and had his leg amputated in oct. for bone cancer. what i’m wondering is how long it’s been going on and, some of his behaviors have changed.
he started peeing in the house and drinking obscene amounts of water, which i thought was a reaction to his food.
see… we’ve changed his food to the timberland ocean blue, that’s supposed to help cool them down. if anyone knows how this particular ffod cools them down that would be helpful to me(does it make them want to drink more water, ect?).
don’t freak out either, he’s going to the vet as soon as they open.
we took him to the vet and had his chest x-rayed. there were several tumors in his lungs and his sternum is where osteosarcoma made it’s new home.
the vet said that if the tumors were that bad in the lungs then it was very likely that the cancer had metastisized to his brain causing the seizures.
the vet also said that herc would only have about 6 wks with an anti seizure med. at the most.
so instead of putting him through all of that, i gave him some peanut butter cups and put him down.
he was happy right up until the end, so…

that you so much for all of your support.