Gregory T. MacLennan, MD is currently the Division Chief of Anatomic Pathology at Case Western Reserve University. Starting in 2008, he has been a professor of pathology and urology & oncology at CWRU. Since 2006, he has been the director of the Seidman Cancer Center Tissue Procurement & Histology Facility. He is also the Senior Pathologist at University Hospitals since 1995. He is also a member of numerous boards of various journals, including Cancer, Journal of Clinical Pathology, and American Journal of the Medical Sciences.

Research Interests
Dr. MacLennan's core area of research is genitourinary pathology, which includes the reproductive and urogenital systems. He spends most of his time committed to diagnostic surgical pathology and cytopathology. He has a particular interest in genitourinary pathology. Much of his time is committed to diagnostic surgical pathology and cytopathology. His research has been predominantly clinically oriented, in collaboration with urologists, oncologists and other pathologists, but has also involved collaborations with basic scientists.