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Learn More About Proton Therapy
Learn More About Proton Therapy

Leadership Team

We have a world-class team of industry veterans and seasoned executives, all of whom share a common vision of delivering on the therapeutic promise of proton therapy for patients worldwide.


  • Lawrence Yuan Tian, Ph.D.


    Lawrence Yuan Tian, Ph.D.


    Mevion has benefited from Dr. Lawrence Tian’s leadership as a member of the board of directors since 2015 and was appointed Chairman in 2018. Dr. Tian brings a wealth of experience from the life sciences and medical device industry to this role. He is a Founding Partner of YuanMing Capital, a leading private equity firm which focuses on the investment in pharmaceutical research and development, innovative medical devices and high-end medical services in both China and the United States. He also serves as the Chairman of Investment Committee of China Pharmaceutical Industry Research and Development Association, and he is a member of the Biotech Advisory Panel of the Stock Exchange of Hong Kong Limited.

    Dr. Tian also brings experience networking business leaders to the Mevion leadership team. He is the founder and Chairman of the China Entrepreneurs Forum, the most influential business owners association in China, and is the founder of the China-U.S. Business Leaders Roundtable, a prestigious cross-border communication platform.

    Prior to Mevion, Dr. Tian has had successful career as a serial entrepreneur with a strong track record of success. In the financial markets, he founded China International Futures Co., Ltd. (CIFCO) in 1992. CIFCO grew into a leading brokerage firm and achieved the largest market share in China during his chairmanship. He also co-founded Wumart Group in 1994, which is currently the largest supermarket chain in Northern China.

    Dr. Tian obtained his master’s degree and doctoral degree from Wuhan University. He received the China Economics Theory Innovation Award, China’s highest prize for economics. 

  • Tina Tianning Yu, Ph.D.

    Chief Executive Officer & President

    Tina Tianning Yu, Ph.D.

    Chief Executive Officer & President

    Mevion’s Chief Executive Officer and President, Dr. Tina Yu, brings more than twenty years of professional experience working in the life sciences sector and the financing world of the healthcare industry. She is a member of Worcester Business Journal Class of 2021 Power 50, a list of the most influential Central Massachusetts professionals. As a Co-Founding Partner of YuanMing Capital, a healthcare fund focusing on cross-border investment strategies, Dr. Yu led the investment in BeiGene, Ascentage Pharmaceuticals, and Mevion Medical Systems. Prior to that, Dr. Yu worked for Vision Capital, an NYC-based investment management firm, as a Director of Investment, responsible for US biotech and China sectors. Before becoming an investor, Dr. Yu was a senior research scientist at Wyeth BioPharma, where she specialized in therapeutic protein development. She also worked for Fidelity, Morgan Stanley, and Genzyme. Dr. Yu founded Matching Capital Partners to provide cross-border consulting services in the life sciences industry.

    Dr. Yu holds a Ph.D. in Chemistry from Princeton University, an MBA from Harvard Business School, and a B.S. in Biology from the University of Science and Technology of China.

  • Curt Kienast

    Chief Operating Officer

    Curt Kienast

    Chief Operating Officer

    Curt is an experienced executive who has been a part of our team since 2007. He previously worked in the defense industry and later joined the healthcare field as the president of Healthcare Technology Consulting, which focuses on quality and regulatory consulting. After participating in several mergers and acquisitions in the consulting industry, Curt joined us as our director of software quality. Through his thirteen years with us, Curt has held leadership positions in quality, engineering, and service. 
    Curt holds a Bachelor of Science in computer engineering from Embry-Riddle Aeronautical University.

  • Mark Jones

    Chief Technology Officer

    Mark Jones

    Chief Technology Officer

    Mark joined Mevion in 2006, bringing a wide range of engineering expertise. Today, he serves as Mevion's Chief Technology Officer. During his nearly 30 years in the industry, Mark led the development of many successful medical devices and earned five patents while developing MRI and CT imaging products at Analogic Corporation, cardiac imaging products at XRE Corporation, and most recently, genetic research and molecular diagnostics products at Affymetrix.

    Mark holds a Bachelor of Arts in mechanical engineering from Norwich University and a Master of Science in engineering management from the Gordon Institute of Tufts University.

  • Lionel G. Bouchet, Ph.D.

    Senior Vice President, Commercial Development, North America

    Lionel G. Bouchet, Ph.D.

    Senior Vice President, Commercial Development, North America

    With a deep clinical understanding of proton therapy, Lionel serves as Mevion’s Senior Vice President of Commercial Development in North America. He previously led the development and application of image-guided and radiosurgery product lines at Varian Medical Systems. Prior to Varian, Lionel was an assistant professor in the Department of Neurological Surgery at the University of Florida Gainesville, where he developed the image-guided and radiosurgery clinical research program for the school’s Brain Institute.

    Lionel has a Master of Science in nuclear engineering from Texas A&M University and a Ph.D. in medical physics from the University of Florida. He also holds an engineering degree from the Institut Polytechnique de Grenoble in France.

  • Stanley “Skip” Rosenthal, Ph.D.

    Senior Vice President, Clinical Affairs

    Stanley “Skip” Rosenthal, Ph.D.

    Senior Vice President, Clinical Affairs

    Skip's thirty years of radiation oncology and proton therapy experience began at the Harvard Cyclotron Laboratory in 1991. While working there until it closed in 2002 and at Massachusetts General Hospital (MGH) until 2005, Skip’s work included the creation of novel treatment planning and patient positioning for particle therapy. He served on the MGH leadership team that oversaw the installation and operation of the world’s first commercial proton facility, the Northeast Proton Therapy Center (now named the Burr Proton Therapy Center) at MGH. Skip led their medical physics program and invented a computerized digital imaging system for patient setup. With CMS (now Elekta), he developed and commissioned the first commercial treatment planning system for proton therapy and has provided consultation for the proton centers at Indiana University and Loma Linda University.

    Skip joined Mevion in 2005 and is the senior advisor for the next generation of clinical systems and customer success. He created and leads Mevion's customer education, training and user programs and has trained hundreds of physicians and physicists in the art and science of proton therapy.

    He has held an assistant professorship at Harvard Medical School and appointments at the Massachusetts Institute of Technology (MIT), Boston University Medical School, and University of Massachusetts Medical School. Skip holds a BS in Physics and Mathematics from Brooklyn College CUNY, a Master’s of Science, and a Ph.D. in Physics from Brandeis University. He is board-certified in therapeutic radiologic physics, a well-published clinical author, and over his career, has contributed to the treatment of over 10,000 patients.

  • Ping Hu, Esq.

    Vice President, Legal and Compliance

    Ping Hu, Esq.

    Vice President, Legal and Compliance

    Ping, a seasoned attorney with extensive experience in a broad spectrum of practice areas, joined Mevion in 2019. As Mevion's General Counsel, Ping leads the legal team in the company and advises the company, its management and the Board of Directors on all legal matters on a global basis. Ping also serves as the Chief Compliance Officer and oversees the Regulatory Affairs and Quality Assurance team at Mevion.

    Before joining Mevion, Ping practiced law for over a decade in national and international law firms. Prior to his legal career, Ping worked as a software engineer in the high tech industry. He received a B.S. degree with the highest distinction from Fudan University, an M.S. degree from Dartmouth College, and a J.D. summa cum laude from Suffolk University Law School. Ping is licensed to practice law in Massachusetts, District of Massachusetts, and United States Patent and Trademark Office.

  • Townsend Zwart, Ph.D.

    Vice President of Advanced Development

    Townsend Zwart, Ph.D.

    Vice President of Advanced Development

    Townsend joined Mevion in 2005. He has held leadership roles in Accelerator Development and Beam Delivery Systems and has served as the VP of Advanced Development since 2013. He was instrumental in the design and development of Mevion’s ultra-compact 250 MeV superconducting synchrocyclotron and holds several patents in subjects related to the synchrocyclotron and pencil beam scanning.

    Prior to his employment at Mevion, Townsend held research positions at Harvard Cyclotron, where he treated cancer patients with their historic 160 MeV synchrocyclotron, and MIT, where he developed and commissioned many accelerator systems, including Ion Sources, Magnets, Beam Instrumentation, Controls, and RF.

    Over the course of his career, Townsend has collaborated on accelerator development projects with scientists at many National labs in the US and Europe, including Brookhaven, Fermilab, Deutch Electron Synchrotron (Germany), National Institute for Subatomic Physics (Netherlands) and the Budker Institute for National Physics (Russia).

    Townsend holds a Ph.D. from Boston University in Applied Physics with a concentration on Accelerator Systems and a B.A. Physics degree from Dartmouth College.

  • Sandra Rousselle, SPHR, SHRM-SCP

    Vice President of People Operations

    Sandra Rousselle, SPHR, SHRM-SCP

    Vice President of People Operations

    Sandra joined Mevion in 2018, bringing a wide range of global human resource experience. As a strategic business partner and leader, Sandra has a proven history of implementing employee engagement, development, and management programs that support the achievement of business goals and objectives while positively impacting the employee experience. Before Mevion, Sandra’s 25-year experience spans high-tech and industrial companies including Advanced Instruments LLC, Fresenius Medical Care, and Hollingsworth & Vose Company.

    Sandra is a certified Senior Professional in Human Resources (SPHR) and SHRM-SCP; and also serves as a Subject Matter Expert for the Human Resources Certification Institute (HRCI) providing periodic industry feedback and participating in SPHR exam writing campaigns.


Mevion's Technical Advisory Board provides strategic guidance and direction for our clinical and development strategy. They believe in and support Mevion's mission: to provide superior proton therapy to as many cancer patients as possible.

Nancy Tarbell, MD
C.C. Wang Professor, Radiation Oncology, Harvard Medical School
Head, Pediatric Radiation Oncology, Massachusetts General Hospital
Dean, Academic and Clinical Affairs, Harvard Medical School

Jeffrey Bradley, MD
Professor and Chair of Radiation Oncology
Emory University

Hak Choy, MD
Chair of the Department of Radiation Oncology 
UT Southwestern

Brian Collins, MD
Medical Director of the Department of Radiation Medicine
Medstar Georgetown University Hospital

Minesh Mehta, MD
Deputy Director & Chief of Radiation Oncology
Miami Cancer Institute

Wayne Newhauser, Ph.D.
Chair of Medical Physics
Louisiana State University

Stephanie Perkins, MD
Director, S. Lee Kling Proton Therapy Center, Chief of Pediatric Radiotherapy Service
Washington University School of Medicine

Bill Salter, Ph.D.
Professor & Chief of the Division of Medical Physics, Senior Director of Radiation Oncology
University of Utah School of Medicine, Huntsman Cancer Institute