10
Views
22
CrossRef citations to date
0
Altmetric
Original Article

Some problems related to the clinical use of thermal isoeffect doses

Pages 329-336 | Published online: 16 Apr 2010
 

Abstract

The well-known biological isoeffect relationship between treatment time and temperature has been suggested as a basis for a general biological heat dose unit which could be used to compare the effect of different heat treatment schedules. This is frequently expressed as ‘equivalent heating time at 43°C’. Such a conversion has in experimental studies been shown to be effective in comparing single heating schedules. However, clinical treatment has some features which may strongly influence the usefulness of an isoeffect heat dose. Firstly, the heat distribution is generally heterogeneous and fluctuates with time, which in some situations results in increased damage due to step-down heating. Secondly, in the situation where hyperthermia and radiation are given simultaneously, the time-temperature relationship may be different from that in the case of heat alone, and from the effect of heat given as an adjuvant to radiotherapy. Thirdly, most clinical treatments are given as fractionated treatments, and it is almost certain that thermotolerance may influence the biological heat effect to some extent However, with the unknown kinetics of thermotolerance the magnitude of this phenomenon cannot be predicted.

A series of experiments in a C3H mammary carcinoma were performed in order to analyse some of these problems.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.