6Rs of Radiation Oncology

  • Renu Madan
  • Divya Khosla


The basic aim of delivering radical radiotherapy is to deliver maximum dose to the target while sparing normal tissues as much as possible. Knowledge about the 6Rs of radiotherapy namely repair of sublethal damage in normal tissues, reoxygenation of the tumor cells, redistribution of the tumor cells into more radiosensitive phase, radiosensitivity, and remote (bystander effect) is very important in achieving this goal. The chapter describes the 6Rs of radiotherapy and its clinical significance.


Repair Reoxygenation Redistribution Repopulation 


  1. 1.
    Cox JD, Ang KK. Radiation oncology: rationale, technique, results. 8th ed. St. Louis, MO: Mosby Elsevier; 2002.Google Scholar
  2. 2.
    Harrington K, Jankowska P, Hingorani M. Molecular biology for the radiation oncologist: the 5 Rs of radiobiology meet the hallmarks of cancer. Clin Oncol. 2007;19:561–71.CrossRefGoogle Scholar
  3. 3.
    Fyles A, Milosevic M, Hedley D, Pintilie M, Levin W, Manchul L, Hill RP. Tumor hypoxia has independent predictor impact only in patients with node-negative cervix cancer. J Clin Oncol. 2002;20:680–7.CrossRefGoogle Scholar
  4. 4.
    Nordsmark M, Bentzen SM, Rudat V, Brizel D, Lartigau E, Stadler P, Overgaard J. Prognostic value of tumour oxygenation in 397 head and neck tumors after primary radiation therapy: an international multi-centre study. Radiother Oncol. 2005;77(1):18–24.CrossRefGoogle Scholar
  5. 5.
    Suwinski R, Sowa A, Rutkowski T, Wydmanski J, Tarnawski R, Maciejewski B. Time factor in postoperative radiotherapy: a multivariate locoregional control analysis in 868 patients. Int J Radiat Oncol Biol Phys. 2003;56:399–412.CrossRefGoogle Scholar
  6. 6.
    Begg A. Molecular targeting and patient individualization. In: Joiner M, van der Kogel A, editors. Basic clinical radiobiology. 4th ed. London: Hodder Arnold; 2009.Google Scholar
  7. 7.
    Mothersill C, Seymour CB. Review: Radiation-induced bystander effects: past history and future perspectives. Radiat Res. 2001;155:759–67.CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • Renu Madan
    • 1
  • Divya Khosla
    • 1
  1. 1.Department of Radiotherapy and OncologyPost Graduate Institute of Medical Education and ResearchChandigarhIndia

Personalised recommendations