Evaluation of 3D-CRT and VMAT Radiotherapy Plans for Left Breast with Regional Lymph Nodes Irradiation

Introduction: Radiation therapy after breast surgery is an integral part of the treatment early cancer. The goal radiation to achieve best possible coverage planning target volume (PTV), while reducing dose organs at risk (OARs) which are normal tissues whose sensitivity irradiation could cause damage that can lead modification plan. In last decade, oncologist started use Intensity Modulated Radiotherapy (IMRT) and Volumetric Arc Therapy (VMAT) for irradiating breast, in order better distribution PTV OAR. aim this study compare 2 external radiotherapy techniques (VMAT vs 3D) patients with node-positive left Patients Methods: We randomly selected 10 cases postoperative cancer our hospital. all female, average age was 45.4 years old, primary lesions breast. ANOVA test used mean difference between subgroups, p value Results: Dose histogram (DVH) analyze each evaluation clinical (CTV) (OARs). Compared 3DCRT plans, VMAT provided more uniform regional lymph nodes. max point tVMAT lower on (106.4% versus 109% 3DCRT). OAR sparing improved tVMAT, a V17Gy lung (27.91% 30.04% 3DCRT, V28Gy (13.75% 22.34% = 0.01). also found V35Gy heart plan (p 0.02). On contrary, contralateral than (0.59 Gy 3.65 Gy, 0.00). Conclusion: both types plans meet dosimetry demands has conformity, but 3CDRT provide (breast lung) avoid secondary cancers.