I know someone whose dog had just had chemo for bone cancer and sailed through it. Apparently the issue is whether the dog is happy and relaxed being handled at the vets and will calmly tolerate the IV, also there is an issue about loss of appetite. It doesn't usually make dogs ill like it makes humans ill although that depends a bit on what the chemo drugs consist of. I don't think they will say "needs". In dogs chemo is not a cure, its a life prolonger, when it works, so its not so much a "needs" as an option. You really need to talk to your vet.