Dr. Alexandros D. Polydorides is Professor and Vice Chair for Clinical Research in the Department of Pathology, Molecular and Cell Based Medicine at the Icahn School of Medicine at Mount Sinai and Attending Pathologist in the Division of Gastrointestinal Pathology at the Mount Sinai Hospital. He is also Professor in the Department of Medicine (Dr. Henry D. Janowitz Division of Gastroenterology), Professor in the Windreich Department of Artificial Intelligence and Human Health, Professor in the Department of Medical Education, Master Educator at the Institute for Medical Education, and the Director of Undergraduate Medical Education in Pathology, all at the Icahn School of Medicine at Mount Sinai.

A native of Athens, Greece, he graduated from Princeton University in 1995 (B.A., Summa cum laude in Molecular Biology with a Certificate in Biomedical Engineering) and the Tri-Institutional MD/PhD program in 2003, obtaining his M.D. from Weil Cornell Medical College and his Ph.D. from Rockefeller University, where he studied the biochemical properties of neuronal RNA-binding proteins in the laboratory of Dr. Robert B. Darnell. He completed his Residency in Anatomic Pathology at New York Presbyterian Hospital/Weil Cornell Medical Center in 2006, where he was also Chief Resident, followed by a Fellowship in Oncologic Surgical Pathology at Memorial Sloan-Kettering Cancer Center in 2007. He obtained specialized training with a Fellowship in Gastrointestinal Pathology at the University of Michigan in 2008, under the mentorship of Dr. Henry Appelman and Dr. Joel Greenson.

He has clinical expertise in the diagnosis of dysplasia and carcinoma in the setting of chronic inflammatory disorders of the gastrointestinal tract such as Barrett esophagus, Helicobacter pylori gastritis, and idiopathic inflammatory bowel disease (IBD), including ulcerative colitis and Crohn disease. His research concerns the histomorphologic features and prognostic implications of various neoplasms and preneoplastic conditions in the tubular gastrointestinal tract. He has authored numerous peer-reviewed original articles, expert reviews, and book chapters, regularly presents lectures at national and international pathology meetings, and is actively involved in teaching, training, and mentoring of medical students, residents, fellows, and junior faculty. Dr. Polydorides is the recipient of many awards, honors, and distinctions, a prominent member of academic pathology societies, and a member of the editorial board and regular reviewer for distinguished academic pathology journals.