Focus areas Dr. Hay's efforts have helped develop a computerized database of more than 3,500 patients with differentiated thyroid carcinoma (DTC) initially treated at Mayo Clinic over seven decades. As part of this research, patients and their archival tumor tissues have been studied to provide further information on molecular pathogenesis, identify patients at high risk of cancer-related death, and define a rational management program for both initial therapy and subsequent follow-up.