It's rare that I venture over to the dog section but this thread caught my eye. I'm so glad all is well w/Nova. My RB peeka-poo dog Charmin had that same type of lump on her back and it was rock hard. When I took her in to my vet, he said "No need to biopsy. I'm positive it's cancer and it's coming out now." She didn't need chemo or any further treatment. We were lucky. And my vet said that the tumor was so obviously malignant that he was afraid it had spread but it hadn't. So when I read your thread, I thought "Oh no, please." I'm soooo happy that Nova is ok.