Ben K. Seon, a senior faculty member and distinguished immunology scientist at Roswell Park Comprehensive Cancer Center across six decades, died Dec. 17, 2025. He was 89.
Dr. Seon had a remarkably long and impactful career, reaching a milestone few scientists ever achieve—U.S. Food and Drug Administration approval of a drug based on his innovative ideas and fundamental discoveries.
First appointed to the Roswell Park faculty in 1967, Dr. Seon was a pioneer in the field of cancer immunotherapy, focused on antibody-based therapies in particular.
“I didn’t take the conventional approach. I decided to develop a new system for isolating antigens,” Dr. Seon said in 2019. “My father died from stomach cancer when I was a high school student, and my brother died of cancer many years ago in his 50s. So, it’s always been in my mind that hopefully someday I could find a new cancer drug, a better cancer drug.”
His devotion, drive and perseverance in the laboratory paid off. Dr. Seon developed a strategy to isolate the genetic protein CD79b—a pivotal discovery that led to development of the immune-based therapy known as polatuzumab vedotin, sold by Genentech Inc. under the brand name Polivy.
The FDA in 2019 approved Polivy as treatment for an advanced and aggressive form of large B-cell lymphoma (DLBCL), and later approved a modified form known as an antibody-drug conjugate for additional applications in patients with B-cell lymphomas—the most common type of non-Hodgkin lymphoma in the United States and worldwide, affecting more than 18,000 new patients in the U.S. alone each year.
“All of us who got a chance to know Dr. Ben Seon and watch him work admired him greatly,” said Roswell Park President, CEO, and M&T Bank Presidential Chair in Leadership Candace S. Johnson. “His entrepreneurial approach made him very creative but also very practical. He was always formulating new ideas and thinking of next steps, of ways to make a difference for patients.”
“Dr. Seon’s work truly revolutionized the way we treat B-cell lymphoma around the world, and he was a beloved scientist among his colleagues at Roswell Park,” said Francisco J. Hernandez-Ilizaliturri, The Mary Alice and Ross Eckert Endowed Chair to Support the Advancement of Lymphoma Research at Roswell Park.
Retiring from his full-time role as professor of oncology in 2014, Dr. Seon continued his research as an Emeritus Professor until 2025. In 2023, the Roswell Park Department of Immunology awarded Dr. Seon a Lifetime Achievement Award recognizing the depth and impact of his influence on cancer research and patient care.
My father died from stomach cancer when I was a high school student, and my brother died of cancer many years ago in his 50s. So, it’s always been in my mind that hopefully someday I could find a new cancer drug, a better cancer drug.
Ben K. Seon
“Dr. Seon was an exceptional scientist, a titan in his field, and a gentleman. He will be immensely missed, but I deeply believe that the impact of his personal and professional legacy will forever persist,” said Scott Abrams, Jacobs Family Endowed Chair of Immunology at Roswell Park and a colleague of Dr. Seon.
Dr. Seon was born in the Fukuoka Prefecture, Japan, in 1936, and joined Roswell Park shortly after earning his doctorate in biochemistry from the Osaka University of Osaka, Japan, in 1966. He was active in professional societies including the American Association for Advancement of Science, the American Association for Cancer Research, and the American Association of Immunologists.
Services were held privately by Dr. Seon’s family, which includes his wife, Takako Seon, children Dr. Carl (Anita) Seon, Amy Seon and Mae Seon, and a granddaughter, Jillian.
Memorials may be directed to Roswell Park at roswellpark.org/giving, and online condolences may be shared at TheDietrichFuneralHome.com.
