Systemic effects of local radiotherapy

Lancet Oncol. 2009 Jul;10(7):718-26. doi: 10.1016/S1470-2045(09)70082-8.


Radiotherapy is generally used to treat a localised target that includes cancer. Increasingly, evidence indicates that radiotherapy recruits biological effectors outside the treatment field and has systemic effects. We discuss the implications of such effects and the role of the immune system in standard cytotoxic treatments. Because the effects of chemotherapy and radiotherapy are sensed by the immune system, their combination with immunotherapy presents a new therapeutic opportunity. Radiotherapy directly interferes with the primary tumour and possibly reverses some immunosuppressive barriers within the tumour microenvironment-ideally, recovering the role of the primary tumour as an immunogenic hub. Local radiation also triggers systemic effects that can be used in combination with immunotherapy to induce responses outside the radiation field.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Animals
  • Antineoplastic Agents / administration & dosage
  • Bystander Effect / immunology
  • Bystander Effect / radiation effects
  • Combined Modality Therapy
  • Granulocyte-Macrophage Colony-Stimulating Factor / administration & dosage
  • Humans
  • Immune System / radiation effects*
  • Immunotherapy*
  • Neoplasms / genetics
  • Neoplasms / immunology*
  • Neoplasms / radiotherapy*
  • Neoplasms / therapy
  • Rodentia
  • Signal Transduction / immunology
  • Signal Transduction / radiation effects


  • Antineoplastic Agents
  • Granulocyte-Macrophage Colony-Stimulating Factor