Canine lymphoma

Our dog was diagnosed 2 weeks ago, he had been losing weight, vomiting intermittently and no appetite for 2 weeks prior to the vet visit. (He's always had a sensitive stomach and bouts of picky eating/vomiting from refusal to eat) I've done lots of research but I'm looking for people's stories/ timelines they experienced. It varies so much. We have chosen not to do chemo due to his age, he's eating and drinking well now on the prednisone and seems relatively fine with some nights of heavier breathing but not necessarily labored breathing. He's been my best buddy for 11 years now and my daughter adores him, bottom picture is from a few days ago and you can see he's become rather skinny.