Journal of Medical Physics
 Home | Search | Ahead of print | Current Issue | Archives | Instructions | Subscription | Login  The official journal of AMPI, IOMP and AFOMP      
 Users online: 374  Home  EMail this page Print this page Decrease font size Default font size Increase font size 
Year : 1986  |  Volume : 11  |  Issue : 3  |  Page : 339

A Theoretical Approach To The Effect Of Dose Modifiers On Fractionation In Radiotherapy

Correspondence Address:
D Krishnan

Login to access the Email id

Source of Support: None, Conflict of Interest: None

Rights and PermissionsRights and Permissions

The time-dose relationship in the practice of radiotherapy is important fox fractionation. Empirical formulae are available t o calculate the effective therapeutic dose for different fractionation schedules. These formulas however could not be directly used if the treatment includes dose modifiers much as chemical sensitizers, since they are the net resultant of many radiobiological parameters such as the 4R’s of radiotherapy. Effect of dose modifiers on these radiobiological parameters will help to analyse the effect on time-dose relationships. One of the many factors is the relation between dose and cell killing. Theoretical approach to the survival of the irradiated cell population has led t o various - mathematical formulations, which are available in the literature. Interpretation of these formulas with respect to fractionation scheme will be useful. One approach adopted by us will change the two-component male1 of cell killing. The survival curve parameters will change when dose modifiers such as hypoxic cell senstitizers are present during irradiation. The effect of this on both the dose per fraction and the fractionation schedule can be theoretically estimted, assuming the same therapeutic gain. Calculation suggest that a suitable fractionation schedule will need higher dose per fraction than the conventional dose and that the dose modifiers will have very small effect if conventional fractionation schedule is followed. It is hoped that this work will suggest conditions under which animal or human therapeutic trials should be conducted to decide whether a dose modifier is useful in practice or not.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded28    
    Comments [Add]    

Recommend this journal