[Use of lithium fluoride in clinical dosimetry. Application to the measurement of the dose delivered to axilla by iridium 192 with endocurietherapy for carcinoma of the breast].

The aim of the work was the evaluation of the dose delivered to the axilla during endocurietherapy for carcinoma of the breast using Iridium 192. The position of the radioactive material with respect to the axillary zone differing with the patient seated or lying, the authors carried out an vivo dosimetric study using Lithium fluoride. They refer to the chief properties of Lithium fluoride which render it the dosimetric agent of choice for clinical work and give details of their experimental conditions, stressing the problems encountered in practice (response in relation to dose, mass of thermoluminescent powder to use, fading, regeneration etc.). They then describe the technique used for placing the thermoluminescent dosimeter in the axillary zone adjacent to the target volume irradiated. Results concerning 43 patients made possible the establishment of a significant correlation between the dose delivered to the axillary region and the site of implantation of the radioactive material in the breast, and show that, with identical tumour doses, this dose is little dependent upon the structure of the radioactive implant itself. They conclude that the dose delivered to the axillary region is of the order of 25% of the tumour dose if the radioactive implant is localised in the axillary tail, 10% if it is in the upper outer quadrant and negligeable if it is elsewhere.