Exact Sciences Corporation announced that Paul J. Limburg, M.D., M.P.H., has been appointed the company's co-chief medical officer. Dr. Limburg is a gastroenterologist and a professor of medicine at Mayo Clinic. He is also a co-leader of the Cancer Prevention and Control program within Mayo Clinic Cancer Center. He is a medical advisory board member of Fight Colorectal Cancer, a patient education and advocacy group.