Sorry Oliver is having to go through this. My current dog, a beagle, hasn't had this diagnosis, but I had a Jack Russell that did. It was on his ankle and the vets ignored it even after it was brought to their attention. By the time we got him to a specialist it had progressed too quickly into his lymphatic system and we only had him for about a month after his diagnosis. It was difficult to go through, mostly because we didn't have any options. I hope Oliver is able to overcome this.