Date Approved
7-30-2025
Graduate Degree Type
Project
Degree Name
Medical Dosimetry (M.S.)
Degree Program
Health Professions
First Advisor
Bethany Marshall
Second Advisor
Kristen Vu
Academic Year
2024/2025
Abstract
Abstract 2 Left-sided breast cancer poses significant cardiac and pulmonary risks during radiation therapy, requiring techniques that optimize target coverage while minimizing exposure to critical organs. This study aimed to compare Volumetric Modulated Arc Therapy (VMAT) and Modern Advanced 3D Radiation Therapy (MA-3DRT), specifically Radformation’s EZFluence, in the treatment of left-sided breast cancer with nodal involvement. The objective was to evaluate which technique offers superior organ-at-risk (OAR) sparing, improved target coverage, and practical efficiency for clinical implementation. A retrospective dosimetric analysis was conducted on eight patients, each with an existing MA-3DRT plan. VMAT plans were generated using identical CT simulation data to allow for direct comparison. Dosimetric metrics evaluated included target volume coverage for (PTV Supraclavicular, Axilla, and IMNs), dose conformality, and OAR doses to the heart, ipsilateral lung, contralateral lung, and contralateral breast. Statistical comparisons used the Shapiro-Wilk test to assess normality, followed by paired t-tests or Wilcoxon signed-rank tests as appropriate. Results demonstrated that VMAT achieved significantly improved dose conformity and reduced low-dose spread to the contralateral breast (p < 0.05). However, MA-3DRT plans resulted in significantly lower mean heart dose and smaller heart V2500cGy volumes, indicating better cardiac sparing. Ipsilateral lung doses were comparable between techniques, while VMAT showed increased complexity and longer planning time. In conclusion, while VMAT offers superior conformity and reduced exposure to contralateral structures, MA-3DRT remains advantageous for heart sparing and overall planning simplicity. Selection of the optimal technique should be guided by patient-specific anatomy and institutional resources. This study contributes evidence to support more personalized, evidence- based planning decisions in breast radiation therapy.
ScholarWorks Citation
Sears, Christopher Kyle, ""Comparative Evaluation of Breast Radiation Treatment Planning: Volumetric Modulated Arc Therapy (VMAT) Versus Modern Advanced 3D Planning Techniques (MA-3DRT) —Benefits, Limitations, and Clinical Implications"" (2025). Culminating Experience Projects. 597.
https://scholarworks.gvsu.edu/gradprojects/597
