Joyce A. O’Shaughnessy, M.D. specializes in medical oncology with board certification in both internal medicine as well as medical oncology. She is a Diplomate of the American Board of Internal Medicine with subspecialty certification in medical oncology. Dr. O’Shaughnessy focuses on her practice and clinical research on breast cancer treatment. She is Director of Breast Cancer Research and at Baylor-Sammons Cancer Center and chair of Breast Cancer Research for The US Oncology Network.