Hi Buffy -- I am no expert with TCC...just joined this board myself. But I wanted to share with you that my Baxter was diagnosed early and because of that, our vet says he has the "best chance" of all the dogs she has diagnosed with this terrible disease. I understand you have paid the $600 and that is a lot of cash, but it will be far more if you have to undergo aggressive chemo or other treatments to get control of the TCC (at least for as long as you can). I would counsel you to go for the ultrasound (about $200 in my experience) but be sure the doctor performing it is an expert (and not just on an occasional basis). You could always ask your vet, considering the amount you have paid thus far, to consider a reduction in the fee, or at least offer you payment plan. Maybe there is a teaching hospital in your area? You might want to find out. If you love you dog as much as it sounds like you do, it is better to know if TCC is there, than to hope it isn't. If you ignore it, it WILL only get worse. At least if you know, you can make informed decisions about treatment. Let us know how it goes. I wish you and Georgie only the best! Cathleen