Abstract
BackgroundBreast cancer sensitivity to large fraction size may be enhanced using hypofractionated concomitant boost radiotherapy (CBRT), thereby shortening overall treatment time. This ethics approved, prospective single cohort feasibility study was designed to evaluate the dosimetry and toxicity of CBRT using an intensity-modulated radiotherapy (IMRT) technique, compared with a standard sequential boost technique (SBT). MethodsFifteen women (11 right-sided; 4 left-sided) received 42.4Gy to the whole breast and an additional 10.08Gy to the tumor bed in 16 daily fractions, using IMRT and standard dose constraints. Each patient was replanned with the SBT, using mixed photon–electrons. Clinical target volume (CTV), dose evaluation volume (DEV), and organs at risk (OAR) dose distributions were compared with the SBT. Toxicity and treatment times were prospectively recorded. ResultsAll 15 CBRT plans achieved the desired CTV (V49.9Gy⩾99%) and DEV (V49.9Gy⩾95%), coverage of the boost, compared with only 10 (66.7%, p=0.03), and 12 (80%, p=0.125) SBT plans, respectively. Ipsilateral lung (p<0.0001), and heart (right-sided, p=0.001; left-sided, p=0.13) doses were lower. Grade 3 acute toxicity occurred in 1 (6.7%) patient. At 1year, two (13.3%) additional patients had overall grade 2 late toxicity, compared with baseline. No grade 3–4 late toxicity was observed. ConclusionsCBRT using IMRT improved boost coverage and lowered OAR doses, compared with SBT. Toxicities were acceptable using a daily boost of 3.28Gy. While resource utilization was greater, overall treatment time was reduced.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.