- 作者：Wenyong Tan ; M.D. ; Ph.D.&lowast ; ; &dagger ; ; Dong Liu ; M.Sc.&lowast ; ; Chenbin Xue ; Ph.D.&dagger ; ; Jiaozhen Xu ; M.D.&lowast ; ; Beihui Li ; M.D.&lowast ; ; Zhengwang Chen ; Ph.D.&dagger ; ; Desheng Hu ; M.D.&lowast ; ; Xionghong Wang ; Ph.D.&lowast ; ; tanwyym@yahoo.com.cn
- 关键词：Breast cancer ; Radiotherapy ; Intensity modulation ; Organ at risk ; Cardiac complications
- 刊名：International Journal of Radiation Oncology*Biology*Physics
- 出版年：2012
- 出版时间：1 April, 2012
- 年：2012
- 卷：82
- 期：5
- 页码：1689-1697
- 全文大小：1828 K
Purpose
We investigated whether the heart could be replaced by the anterior myocardial territory (AMT) as the organ at risk (OAR) in intensity-modulated radiotherapy (IMRT) of the breast for patients with left-sided breast cancer.Methods and Materials
Twenty-three patients with left-sided breast cancer who received postoperative radiation after breast-conserving surgery were studied. For each patient, we generated five IMRT plans including heart (H), left ventricle (LV), AMT, LV+AMT, and H+LV as the primary OARs, respectively, except both lungs and right breast, which corresponded to IMRT(H), IMRT(LV), IMRT(AMT), IMRT(LV+AMT), and IMRT(H+LV). For the planning target volumes and OARs, the parameters of dose-volume histograms were compared.
Results
The homogeneity index, conformity index, and coverage index were not compromised significantly in IMRT(AMT), IMRT(LV) and IMRT(LV+ AMT), respectively, when compared with IMRT(H). The mean dose to the heart, LV, and AMT decreased 5.3-21.5 % (p < 0.05), 19.9-29.5 % (p < 0.05), and 13.3-24.5 % (p < 0.05), respectively. Similarly, the low (e.g., V5 % ), middle (e.g., V20 % ), and high (e.g., V30 % ) dose-volume of the heart, LV, and AMT decreased with different levels. The mean dose and V10 % of the right lung increased by 9.2 % (p < 0.05) and 27.6 % (p < 0.05), respectively, in IMRT(LV), and the mean dose and V5 % of the right breast decreased significantly in IMRT(AMT) and IMRT(LV+AMT). IMRT(AMT) was the preferred plan and was then compared with IMRT(H+LV); the majority of dose-volume histogram parameters of OARs including the heart, LV, AMT, both lungs, and the right breast were not statistically different. However, the low dose-volume of LV increased and the middle dose-volume decreased significantly (p < 0.05) in IMRT(AMT). Also, those of the right lung (V10 % , V15 % ) and right breast (V5 % , V10 % ) decreased significantly (p < 0.05).
Conclusions
The AMT may replace the heart as the OAR in left-sided breast IMRT after breast-conserving surgery to decrease the radiation dose to the heart.