Welcome to the board, BruceMM! I hope when things are a little less stressful for you you'll share some pics of your setters with us!
Wish I had some advice for you. We have setters, too, and lost one to hemangiosarcoma many years ago, but the cancer wasn't discovered till it had spread to his lungs.
Are there any homeopathic vets in your area? They may have a few suggestions as to supplements that will help.
When will you get the test results? Hope it's good news!! Keep us posted on Rodin's progress, please?