Biological Models in Treatment Planning

  • Christian P. Karger
Part of the Medical Radiology book series (MEDRAD)

18.8 Conclusion

Several biological models have been developed. Although these models give a correct description of the main characteristics of the radiation response, great caution has to be taken if these models are to be applied to patients.

While the linear-quadratic model provides a good description of experimental settings, a larger uncertainty is involved in the prediction of iso-effects for clinical applications. The more advanced NTCP and TCP models should only be applied for relative, rather than absolute, predictions of effect probabilities. When using relative values, the uncertainty of the predictions should be considered to decide whether a detected difference is really significant. As TCP/NTCP models are currently not completely validated, integration of these models into the cost function of the dose optimisation algorithm is not warranted. Whether it is possible to arrive at fully biologically optimised treatment plans for photon therapy has to be investigated by further research.

In this context, the clinical application of heavy charged particles plays an exceptional role as biological optimisation is routinely performed and an adequate RBE model is an essential prerequisite. The applied RBE model may still contain some degree of uncertainty which has to be considered carefully at treatment plan assessment and dose prescription.


Radiat Oncol Biol Phys Biological Model Linear Energy Transfer Boron Neutron Capture Therapy Normal Tissue Complication Probability 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Christian P. Karger
    • 1
  1. 1.Abteilung Medizinische Physik in der StrahlentherapieDeutsches KrebsforschungszentrumHeidelbergGermany

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