National Association for Proton Therapy (NAPT) is a non-profit organization dedicated to promoting the use of proton therapy as an advanced and effective form of cancer treatment. The NAPT Board of Directors plays a pivotal role in guiding the organization’s mission, vision, and strategic direction. The board is composed of distinguished professionals from various roles within the field of proton therapy, each bringing their expertise, experience, and commitment to advancing proton therapy and supporting cancer patients.
Board of Directors
Executive Committee
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Michael Butkus, PhD
Co-Medical Director/Head of Proton Physics
University of Miami
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Andrew Chang, MD
Medical Director, Pediatrics
California Protons Cancer Therapy Center
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Judy Chatigny
Executive Director
Loma Linda University
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Ashish K. Chawla, MD
Chairman Proton Therapy
Inova Schar Cancer Institute
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Isabelle Choi, MD, FACRO
Director of Research
New York Proton Center
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James Gray, MD
Medical Director
Tennessee Oncology Proton Center
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Steven Holan, MBA
Vice President, Operations
Baptist Health South Florida
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Darrin Kistler
Senior Director, Radiation Services
The University of Kansas
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Mark McDonald, MD
Medical Director
Emory Proton Therapy Center
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Fern Nibauer-Cohen
Director, Patient Engagement & Development
Penn Medicine
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Elizabeth Nichols, MD
Associate Professor
Maryland Proton Treatment Center
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Stephanie Perkins, MD
Director, S. Lee Kling Proton Therapy Center
Siteman Cancer Center
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Helen Shih, MD
Massachusetts General Hospital
Medical Director, MGH Proton Therapy Centers
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Charles Yoo
Vice President of Operations & Finance
South Florida Proton Therapy Institute
Board Advisors
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Leonard Arzt
Board Member, Emeritus / Founder
National Association for Proton Therapy
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Jeffrey Bradley, MD
Professor of Radiation Oncology
University of Penn
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Minesh Mehta, MD
Deputy Director – Chair, Radiation Oncology
Miami Cancer Institute, Baptist Health South Florida