SITC Session at ASTRO Annual Meeting

When:  Oct 26, 2021 from 13:30 to 15:45 (CT)

Leveraging the Power of Radiation Therapy to Modulate Anti-Tumor Immunity

Over the last two decades, radiation therapy (RT) has been acknowledged to convey immunogenicity to an irradiated neoplastic lesion by eliciting pro-inflammatory signals capable to stimulate the immune system. The ability of RT to trigger systemic anti-tumor immunity provides an explanation for the rare but well-established observation of patients experiencing responses in metastatic sites outside of the irradiated field (so-called abscopal effect). Consequently, a widespread interest into harnessing the local and systemic effects of RT with modern immunotherapy (IT) has spread in clinic with a large increase of clinical trials assessing IT-RT combinations. The design of these clinical trials in terms of IT sequence and RT schedule is rooted on murine experimental findings which have demonstrated the synergy between IT and RT. However, the optimal sequence, radiation dose and fractionation regimen are currently being debated. Reason for such conflicting observations presumably rely on several factors, including (but not limited to) the immune landscape of the tumor prior RT, the intrinsic biology of the tumor and the immunosuppressive signals that can also be elicited by RT. Consequently, translation of preclinical findings is complex, calling for a better understanding on how RT and IT can be optimally combined.

This session will provide attendees the opportunity to gain exposure to the latest advances in immuno-radiation. They will be able to determine the pros and cons of ionizing radiations in modulating the immune system, discuss clinical trial design for RT and IO combination and gain insight of potential biomarkers in immunotherapy and radiation oncology.

Learning Objectives:

  • Determine the pros and cons of ionizing radiations in modulating the immune system
  • Identify biomarkers for immunotherapy and radiation oncology
  • Discuss clinical trial design for radiation therapy and immuno-oncology combinations


  • 1:32 PM - 1:52 PM
    Radiation therapy and immune stimulation: from Bench Side to Clinic
    Speaker: Silvia Chiara Formenti MD, FASTRO – Weill Cornell Medicine
  • 1:52 PM - 2:12 PM
    Biomarkers in immunotherapy And Radiation Oncology
    Speaker: Timothy A Chan MD, PhD – Cleveland Clinic Lerner College of Medicine
  • 2:12 PM - 2:32 PM
    Acquired resistance mechanisms to RT and immunotherapy combinations
    Speaker: Andy J. Minn III, MD, PhD – University of Pennsylvania


McCormick Place
2301 S King Dr
Room W185
Chicago, IL 60616