8.2 - Treatment Factors Affecting Toxicity

What treatment factors can affect acute toxicity?

There are numerous treatment factors which can alter the acute reactions seen:

  • The dose to the organ in question has a major role to play in the amount of toxicity that develops
  • The fractionation of dose is of small importance in early reactions (but of critical importance in late reactions)
  • The total treatment time has a major impact on early effects. Longer treatments will allow tissue to repopulate and maintain its viability (minimal effect on late effects)
  • The use of bolus can increase dose to the skin and increase effects there
  • The use of shielding can reduce dose to many structures and reduce dose
  • The dose rate can impact the effects seen; low dose rate will tend to cause reduced cell kill for a certain dose and eliminate the quadratic component of cell survival curves