editors, Piper M. Treuting, DVM, MS, Diplomate, ACVP, Associate Professor, Chief of Comparative Pathology Department of Comparative Medicine Adjunct Associate Professor, Department of Pathology University of Washington School of Medicine, Seattle, WA, United States, Suzanne M. Dintzis, MD, PhD, Associate Professor, Department of Anatomic Pathology University of Washington School of Medicine, Seattle, WA, United States, Kathleen S. Montine, PhD, ELS, Senior Principal Research Scientist, Department of Pathology University of Washington School of Medicine, Seattle, WA, United States