, has been appointed the University of Chicago Health System leader for Radiation and Cellular Oncology.

In his expanded role, which took effect in November, Weichselbaum is leading efforts to bring radiation therapy to patients at the University of Chicago Medicine, including in Chicago’s suburbs and in Northwest Indiana.

"Dr. Weichselbaum’s appointment supports our continued growth and innovation in cancer care and research," said , Executive Vice President for Medical Affairs at the University of Chicago. "Radiation oncology is a crucial part of our work to tailor treatment for all our cancer patients, and support them at every step of their recovery."

UChicago Medicine's cancer program is ranked No. 1 in Illinois by . The health system is constructing the state's , which will improve patient experience, reduce health disparities and accelerate scientific discoveries. The building will be .

In his broadened role, Weichselbaum will have system-level oversight of Radiation and Cellular Oncology. He will build on his successful track record managing and improving radiation therapy services across sites in the UChicago Medicine health system and work to ensure all processes align with its academic and clinical missions.

In addition to his position as a health system leader, Weichselbaum will continue in his role as Chair of the Department of Radiation and Cellular Oncology. The Department has seen significant growth and advancements, including:

  • Maintaining Illinois’ largest integrated academic program for radiation oncology, encompassing sites at Hyde Park, Ingalls Memorial, Orland Park, Silver Cross Hospital, Saint Joseph Hospital and the University of Illinois at Chicago (UIC). The program expanded to Indiana in April 2024 with the opening of UChicago Medicine Crown Point.
  • A longstanding clinical partnership and joint residency program with UIC, supporting innovation in patient experience and specialty education.
  • A commitment to basic, translational and clinical research and interdisciplinary collaboration. This has produced a track record of practice-changing discoveries and treatment paradigms, including progress in biophysics and radiotherapy physics.
  • Collaboration with other UChicago departments to recruit basic science faculty in Chemical Biology and Immunology. New faculty have worked to complement ongoing research in DNA repair, mechanisms of metastasis and nanotechnology.

At UChicago, Weichselbaum also serves as a Co-Director of the . A renowned translational researcher, he studies the mechanisms of tumor spread and how radiation therapy and immunotherapy can be better used to treat cancer. He is known for his landmark clinical and basic science investigations into “”; conducted with UChicago colleague Samuel Hellman, MD, this work describes an intermediate state of cancer that can be treated or controlled in part with ablative treatments, such as stereotactic radiotherapy.

Weichselbaum maintains an active lab and is principal or co-principal investigator on five grants from the National Institutes of Health.

Recognized widely for his contributions to radiation oncology, Weichselbaum was named as one of OncLive’s 2024 “Giants of Cancer Care.” In 2018, he received the American Society of Clinical Oncology’s top prize, the David A. Karnofsky Memorial Award, as well as the American Society for Radiation Oncology’s Gold Medal.

Weichselbaum has been a member of the National Academy of Medicine and the Association of American Physicians since 1997. He was also an editor of Cancer Medicine, a definitive reference textbook compiled to help oncologists and internists apply scientific principles to clinical practice.