Physician Photo

David N. Louis, MD

Pathologist-in-Chief, Massachusetts General Hospital

Benjamin Castleman Professor of Pathology, Harvard Medical School

Dr. David Louis is Benjamin Castleman Professor of Pathology and chair of Mass General Pathology. His clinical practice and research focuses on the molecular basis of brain tumors and the application of molecular diagnostics to their classification.

Department of Pathology


  • Cancer Center
  • Neuro-Oncology (Brain)
Clinical Interests
Autopsy Pathology
Frozen Section Pathology
Boston: Massachusetts General Hospital
Medical Education
MD, SUNY at Stony Brook School of Medicine
Residency, Albany Medical Center
Residency, Massachusetts General Hospital
Fellowship, Massachusetts General Hospital
Board Certifications
Anatomic Pathology, American Board of Pathology
Neuropathology, American Board of Pathology
Pathology, American Board of Pathology
Patient Age Group
Accepting New Patients
Accepting New Patients


David N. Louis, MD, is the Benjamin Castleman Professor of Pathology at Harvard and chair of Pathology at Mass General Hospital. Dr. Louis' clinical practice and research has focused on the molecular basis of brain tumors and the application of molecular diagnostics to brain tumor classification. He has published more than 250 original articles, as well as numerous reviews, chapters and books. His laboratory was the first to demonstrate that molecular approaches could be used to subdivide malignant gliomas in a biologically relevant manner, and that molecular approaches could be used to predict the response of particular malignant gliomas to specific therapies, work that has led to worldwide adoption of molecular testing for the management of brain tumor patients. As a result, Dr. Louis co-chaired and was the primary editor for the 2007 WHO brain tumor classification and is currently guiding the WHO brain tumor revision expected in 2016. He has received prestigious awards for this work, has served on multiple advisory and editorial boards, and has authored and/or edited many of the major textbooks in neuropathology. He was co-chair of the Brain Tumor Progress Review Group sponsored by the NIH, and was the founding chair of the Cancer Biomarkers Study Section at the NIH. Under Dr. Louis? chairmanship, Mass General Pathology has become a national leader in molecular diagnostics and pathology informatics, leading to the development of the novel discipline of computational pathology.


Malignant gliomas of the cerebral hemispheres in adults are the most common brain tumors. They are the focus of the David N. Louis Laboratory efforts. Malignant gliomas are classified as astrocytomas, oligodendrogliomas, and oligoastrocytomas. The most aggressive, astrocytoma, is referred to as glioblastoma. Elucidating the molecular basis of glioma formation may impact both diagnostic and therapeutic aspects of clinical neuro-oncology.

Visit the David N. Louis Research Laboratory to learn more.

Bicentennial Corner

Many ‘keen minds’ have worked toward a better understanding of disease to enable improved diagnosis and treatment.

Pathology Associates
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Boston, MA 02114-2696

Phone: 617-726-2966
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