Variation of V105% between pre- and postmerged subfields in field-in-field hypofractionated breast radiotherapy plans

Hypofractionated whole-breast irradiation has emerged as a viable alternative to conventional fractionation. In the field-in-field forward planning technique, a merged plan with 2 to 4 segmental fields is the final plan delivered to the machine. As per the ASTRO guidelines for the hypofractionation regimen, the volume of breast tissue receiving V105% of the prescription dose should be less than 200 cc. However, we have noticed substantial changes to this volume (change in V105% between −55 cc and + 47.1 cc) after merging the subfields.

Source: Medical Dosimetry - May 13, 2019 Category: Radiology Authors: Abhishek Dwivedi, Therese McGarry, Laura Bond, Joel K. Braver, Nrusingh C. Biswal Source Type: research