Kapple, the benefit of Mayo Clinic is that physician teams work together across all Mayo Clinic locations. No matter which location you choose, you have access to expertise in treating insulinoma of multiple physicians. As @ahtaylor points out, her endocrinologist at Mayo Rochester is a leader in insulinomas. I encourage you to call Mayo AZ and Rochester to ask about insulinomas to help inform your decision. Here's the contact information for all 3 campuses: http://mayocl.in/1mtmR63