Characterization of irregular electron beam for boost dose after whole breast irradiation

Publication date: Available online 22 January 2020Source: Reports of Practical Oncology & RadiotherapyAuthor(s): M. Saadeldin Ayat, M. Elwan AzharAbstractIrradiating a tumor bed with boost dose after whole breast irradiation helps reducing the probability of local recurrence. However, the success of electron beam treatment with a small area aiming to cover a superficial lesion is a dual challenge as it requires an adequate dosimetry beside a double check for dose coverage with an estimation of various combined uncertainty of tumor location and losing lateral electron equilibrium within small field dimensions.Aim of workthis work aims to measure the electron beam fluence within different field dimensions and the deviation from measurement performed in standard square electron applicator beam flatness and symmetry, then to calculate the average range of the correction factor required to overcome the loss of lateral electron equilibrium.Material and methodthe electron beam used in this work generated from the linear accelerator model ELEKTA Precise and dosimetry system used were a pair of PTW Pin Point ion chambers for electron beam dosimetry at standard conditions and assessment of beam quality at a reference depth of measurement, with an automatic water phantom, then a Roos ion chamber was used for absolute dose measurement, and PTW 2Darray to investigate the beam fluence of four applicators 6, 10, 14 and 20 cm2 and 4 rectangular cutouts 6x14, 8x14, 6x17 and 8x17 cm2, the seco...
Source: Reports of Practical Oncology and Radiotherapy - Category: Cancer & Oncology Source Type: research