Alaettin Arslan1, Elif Aktas2, Burak Sengul3, Burcu Tekin3. 1. Clinic of Radiation Oncology, Kayseri City Hospital, Turkey, Kayseri, Turkey. alaettin.arslan@gmail.com. 2. Clinic of Radiology, Kayseri City Hospital, Turkey, Kayseri, Turkey. 3. Clinic of Radiation Oncology, Kayseri City Hospital, Turkey, Kayseri, Turkey.
Abstract
INTRODUCTION: We evaluated the dosimetric results of the identification of the left ventricle (LV) and left anterior descending artery (LAD) as organs at risk (OARs) in adjuvant radiotherapy (RT) after breast-conserving surgery (BCS). MATERIALS AND METHODS: Twenty-two patients who had previously received RT in our center were evaluated retrospectively. All patients had undergone BCS operation for left breast cancer. LV and LAD were contoured as OARs on the same simulation CTs for these patients whose treatment was previously completed in which LV and LAD were not defined as OARs. Complying with the initial plans, intensity-modulated RT plans with 7-9 fields were made on the computer. Planning target volume (PTV), homogeneity index (HI), conformity index (CI), monitor unit (MU) values, and doses of OARs were compared using the Wilcoxon signed-rank test (p < 0.05). RESULTS: There were no significant differences in PTV 50 (D 50% and D 98%), PTV 60 (D 2% and D 50%), HI, CI, and MU values when treatment plans and control plans were compared (p > 0.05). While it was possible to protect the heart, LAD, and LV better, LAD and LV were not contoured in the treatment plans, and they received higher doses compared to the control plans (p < 0.05). There was no significant difference in the other OARs. CONCLUSION: In conclusion, it is essential to define the lower anatomical regions of the heart as OARs. Otherwise, the doses taken by these regions are ignored and may be maintained less than possible. In our study, it was shown that LV and LAD doses were significantly reduced even in the same center and planning by the same team.
INTRODUCTION: We evaluated the dosimetric results of the identification of the left ventricle (LV) and left anterior descending artery (LAD) as organs at risk (OARs) in adjuvant radiotherapy (RT) after breast-conserving surgery (BCS). MATERIALS AND METHODS: Twenty-two patients who had previously received RT in our center were evaluated retrospectively. All patients had undergone BCS operation for left breast cancer. LV and LAD were contoured as OARs on the same simulation CTs for these patients whose treatment was previously completed in which LV and LAD were not defined as OARs. Complying with the initial plans, intensity-modulated RT plans with 7-9 fields were made on the computer. Planning target volume (PTV), homogeneity index (HI), conformity index (CI), monitor unit (MU) values, and doses of OARs were compared using the Wilcoxon signed-rank test (p < 0.05). RESULTS: There were no significant differences in PTV 50 (D 50% and D 98%), PTV 60 (D 2% and D 50%), HI, CI, and MU values when treatment plans and control plans were compared (p > 0.05). While it was possible to protect the heart, LAD, and LV better, LAD and LV were not contoured in the treatment plans, and they received higher doses compared to the control plans (p < 0.05). There was no significant difference in the other OARs. CONCLUSION: In conclusion, it is essential to define the lower anatomical regions of the heart as OARs. Otherwise, the doses taken by these regions are ignored and may be maintained less than possible. In our study, it was shown that LV and LAD doses were significantly reduced even in the same center and planning by the same team.
Entities:
Keywords:
Adjuvant radiotherapy; Breast-conserving surgery; Left breast cancer; Left ventricle and left anterior descending artery
Authors: J Cuzick; H Stewart; R Peto; M Baum; B Fisher; H Host; J P Lythgoe; G Ribeiro; H Scheurlen; A Wallgren Journal: Cancer Treat Rep Date: 1987-01
Authors: Shadab Momin; Yang Lei; Neal S McCall; Jiahan Zhang; Justin Roper; Joseph Harms; Sibo Tian; Michael S Lloyd; Tian Liu; Jeffrey D Bradley; Kristin Higgins; Xiaofeng Yang Journal: Phys Med Biol Date: 2022-05-11 Impact factor: 4.174