Dr. Gregory Zanieski joined the Yale School of Medicine and Smilow Cancer Hospital in 2019 and cares for patients with benign or malignant breast disease. His clinical and surgical practice locations are at Smilow Cancer Hospital in New Haven and Shoreline Medical Center in Guilford. Dr. Zanieski received his Medical Degree from the State University of New York at Stony Brook School of Medicine and completed a fellowship in surgical oncology at the University of Pittsburgh Medical Center.

Prior to joining Yale, Dr. Zanieski was a breast oncology surgeon at Vassar Brothers Medical Center in Poughkeepsie, NY for nearly ten years. Dr. Zanieski is a member of the Society of Surgical Oncology, the American College of Surgeons, and the American Society of Breast Surgeons.