My Chloe was very young when she developed it. 5 years old. I knew something was wrong. She was urinating a lot, and drinking a lot of water. Unfortunately, it was inoperable. The Vet who sent away her tests for me, was going to give her Trilostane. But my regular vet prescribed vitamins and stuff. She passed away 2 years later. That was in 2010-I am sure there are more alternatives now. It is as most probably agree, a heartbreaking disease. I felt helpless to help her. I know there is nothing I can say to make you feel better. But I hope Zena stays stable and happy.