Katkıda Bulunanlar Vİİ Peter Pytel, MD Professor Department of Pathology University of Chicago Chicago, Illinois Jerrold R. Turner, MD, PhD Departments of Pathology and Medicine (GI) Brigham and Women’s Hospital Harvard Medical School Boston, Massachusetts Neil D. Theise, MD Professor Department of Pathology Icahn School of Medicine at Mount Sinai New York, New York