Cornelius Thiels, D.O., MBA, FACS, FSSO, is an associate professor of surgery and associate professor of health services research within the Department of Surgery at Mayo Clinic in Rochester. 

As a surgical oncologist in the Division of Hepatobiliary and Pancreas Surgery, he specializes in managing retroperitoneal sarcomas and pancreatic cancer. He also has extensive training and experience in the treatment of neuroendocrine tumors, gastrointestinal stromal tumor (GIST), gastric cancer and metastatic colorectal cancer. Dr. Thiels has special expertise in multimodality treatment of advanced or metastatic cancers, combining surgery with radiation, chemotherapy, or immunotherapy. Dr. Thiels utilizes minimally invasive techniques to perform various operations (including robotic surgery) and leads the Hepatic Artery Infusion Pump Chemotherapy program at Mayo Clinic. 

Dr. Thiels is the associate chair of innovation for the Department of Surgery at Mayo Clinic in Rochester. Together with Dr. Kyle Ettinger, director of innovation, they lead the department's innovation efforts to bring together partners in industry with the goals of fostering product co-development, product commercialization, first-in-human trials, and novel technology adoption within the broader Mayo surgical ecosystem. 

He is also the associate chair of data and analytics for Mayo Clinic's Department of Surgery and the director of a Surgical AI2 (“Squared”) Lab.