American Association for Cancer Research Inaugurates New Leadership During AACR Annual Meeting 2025

Lillian L. Siu, MD, FAACR, begins term as AACR President

CHICAGO – The members of the American Association for Cancer Research (AACR) have welcomed Lillian L. Siu, MD, Fellow of the AACR Academy, as the AACR President for 2025-2026. She was inaugurated today at the AACR’s Annual Business Meeting of Members, held during the AACR Annual Meeting 2025 in Chicago.

Siu is a senior medical oncologist, director of the Phase I Clinical Trials Program, codirector of the Robert and Maggie Bras and Family Drug Development Program, clinical lead for the Tumor Immunotherapy Program, and the BMO Chair in Precision Cancer Genomics at the Princess Margaret Cancer Centre, University Health Network in Toronto, Canada. She is also a professor of medicine at the University of Toronto. Throughout her career, Siu has made crucial contributions to anticancer drug development and translational and clinical research. Her innovative research dedicated to optimizing clinical trial design and execution has resulted in the accelerated discovery and development of novel immunotherapeutics and molecularly targeted therapeutics for patients with head and neck cancers as well as gastrointestinal malignancies.

“I am deeply honored to serve as AACR President during this consequential time,” said Siu. “We have made tremendous progress against cancer in recent years, and it will require creativity and unity in dedication to our mission if we are to maintain this momentum. I look forward to fostering collaboration among our global membership so that we can continue to translate promising cancer research into meaningful improvements in patient care.”

Siu has been a member of the AACR since 1996 and was elected as a Fellow of the AACR Academy in 2024. She served on the AACR Board of Directors from 2017-2020. Siu has been invaluable in shaping AACR Annual Meetings, most recently as one of the chairs of the AACR Annual Meeting 2025 Program Committee. She has previously served as a cochair (2016, 2012) and member (2014) of the Annual Meeting Program Committee; cochair (2016-2017) and member (2014-2016, 2012-2013) of the Annual Meeting Clinical Trials Committee; and chair (2012) and member (2011) of the Annual Meeting Education Committee. She has expertly contributed to other AACR meetings, special conferences, and workshops by serving as scientific committee cochair of the AACR-NCI-EORTC Molecular Targets and Cancer Therapeutics Symposium (2021-2022); cochair of the AACR Special Conference in Cancer Research: Advancing Precision Medicine Drug Development (2020); and cochair (2008-2010) and faculty member (2003-2007, 1998) of the AACR/ASCO Methods in Clinical Cancer Research Workshop.

Siu has provided important guidance as a member (2020-2025) and ex-officio member (2025-2026) of the AACR International-Canada Board of Directors, and member (2019-2025) and ex-officio member (2025-2026) of the AACR Finance and Audit Committee. She has also served as a member of the AACR Asian/Asian American Task Force (2023-present); Clinical Trials Advisory Council (2023-present); International Affairs Committee (2018-2020); AACR-Waun Ki Hong Award for Outstanding Achievement in Translational and Clinical Cancer Research Committee (2017-2019); Regional Advisory Committee on Canada (2016-2019); SU2C/AACR Catalyst™ Initiative Grants Executive Committee (2016); Nominating Committee (2014-2016); Women in Cancer Research Council (2013-2016); Clinical and Translational Cancer Research Grants Committee (2010); Henry Shepard Bladder Cancer Research Grants Scientific Review Committee (2009); AACR-Women in Cancer Research Charlotte Friend Memorial Lectureship Committee (2008); and International Membership Committee (2002-2003). She was chair of the Landon Foundation-AACR Innovator Award for International Collaboration in Cancer Research Committee from 2012-2014.

In addition, Siu has supported the AACR’s journals by serving as one of the editors-in-chief of Cancer Research Communications (2021-present); scientific editor of Cancer Discovery (2011-2021), and member of the Publications Committee (2016-2019).

Siu has been recognized with numerous awards throughout her career, including the American Society of Clinical Oncology David Karnofsky Memorial Award (2024); Canadian Cancer Trials Group Maria Ricci Memorial Lectureship (2023); the American Society of Clinical Oncology International Women Who Conquer Cancer Mentorship Award (2020); the European Society for Medical Oncology Targeted Anticancer Therapies Honorary Award (2020); the University of Toronto Michael Hutcheon Mentor Award (2017), Eaton Research Scholar Researcher of the Year (2016), and Elsie Winifred Crann Memorial Trust Award in Medical Research (2001); and the National Cancer Institute Michaele C. Christian Oncology Development Lectureship and Award (2010). Siu is an elected fellow of the Canadian Academy of Health Sciences (2023) and the American Society of Clinical Oncology (2015).

Siu received her medical degree at the University of Toronto. She completed the Canadian Association of Medical Oncology Fellowship in Oncopharmacology at the Princess Margaret Cancer Centre and a clinical research fellowship in new drug development at the University of Texas Health Science Center at San Antonio.

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ADDITIONAL LEADERSHIP CHANGES

AACR President-Elect

Keith T. Flaherty, MD, FAACR, was elected the AACR President-Elect for 2025-2026. He will assume the Presidency in April 2026 at the AACR Annual Meeting in San Diego. Flaherty is director of clinical cancer research and the Richard Saltonstall Endowed Chair in Oncology at Mass General Cancer Center, a founding member of Mass General Brigham. He is also a professor of medicine at Harvard Medical School and an associate member of the Broad Institute of MIT and Harvard.

Immediate Past President

Patricia M. LoRusso, DO, PhD (hc), FAACR, will serve as the Immediate Past President of the AACR for 2025-2026. LoRusso is the Amy and Joseph Perella Professor of Medicine (Medical Oncology), chief of experimental therapeutics, and associate cancer center director of experimental therapeutics at the Yale School of Medicine. She also leads the phase I disease-aligned research team at Smilow Cancer Hospital.