Comparison of Planning Quality between Intensity Modulated Radiation Therapy, Volumetric Modulated Arc Therapy and Hybrid technique for Left-sided Breast Cancer Irradiation

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วรรณวิษา บำรุงภักดี


This research compares the quality of the radiotherapy plan between the IMRT plan, the VMAT plan, and the hybrid plan for postmastectomy left-side breast cancer irradiation. This is a retrospective study of 15 patients. All three technique of radiotherapy plans were using the Monaco treatment planning system. The IMRT plan uses 7 fix beams and the VMAT plan uses the 2 arcs. The Hybrid plan was combined the IMRT of 3 beams with a weight of 75% and the VMAT of 2 arcs with the weight of 25%. The dosimetric parameters used for evaluating the quality of the three types of treatment plans were including the mean target volume dose(D50), the conformity index (CI), the uniformity index (HI) and the comparison of the radiation dose to organ at risks. The result, when considering PTV_CW, the D50 of the VMAT plan is statistically significant closer to the prescription dose than the IMRT plan and Hybrid plan. The Dmax value of the Hybrid plan is statistically significant lower than the other two plans. VMAT plans and Hybrid plans had the same CI values and are statistically significant better than the IMRT plan. Considering the organ at risks dose, the hybrid plan gave the minimum V5Gy dose to the contralateral breast and the contralateral lung with statistically significant compared to the other two plans. The VMAT plan provided the minimum V30Gy to the ipsilateral lung and the minimum V20Gy to the heart with both statistically significant.

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นิพนธ์ต้นฉบับ (Original Article)


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