- 作者：John Ng ; M.D.&lowast ; ; jon9024@nyp.org ; Igor Shuryak ; M.D. ; Ph.D.&dagger ; ; Yanguang Xu ; Ph.D.&lowast ; ; K.S. Clifford Chao ; M.D.&lowast ; ; David J. Brenner ; Ph.D. ; D.Sc.&dagger ; ; Ryan J. Burri ; M.D.&lowast ;
- 关键词：Secondary malignancy ; Whole-breast irradiation ; Prone breast irradiation ; Hypofractionation ; Early-stage breast cancer
- 刊名：International Journal of Radiation Oncology*Biology*Physics
- 出版年：2012
- 期刊代码：136_03603016
- 类别：med
- 出版时间：15 July, 2012
- 卷：83
- 期：4
- 页码：1101-1106
- 文件大小：601 K
Purpose
The risk of secondary lung malignancy (SLM) is a significant concern for women treated with whole-breast radiation therapy after breast-conserving surgery for early-stage breast cancer. In this study, a biologically based secondary malignancy model was used to quantify the risk of secondary lung malignancies (SLMs) associated with several common methods of delivering whole-breast radiation therapy (RT).Methods and Materials
Both supine and prone computed tomography simulations of 15聽women with early breast cancer were used to generate standard fractionated and hypofractionated whole-breast RT treatment plans for each patient. Dose-volume histograms (DVHs) of the ipsilateral breast and lung were calculated for each patient on each plan. A model of spontaneous and radiation-induced carcinogenesis was used to determine the relative risks of SLMs for the different treatment techniques.
Results
A higher risk of SLMs was predicted for supine breast irradiation when compared with prone breast irradiation for both the standard fractionation and hypofractionation schedules (relative risk [RR] = 2.59, 95%confidence interval (CI) = 2.30-2.88, and RR = 2.68, 95%CI = 2.39-2.98, respectively). No difference in risk of SLMs was noted between standard fractionation and hypofractionation schedules in either the supine position (RR = 1.05, 95%CI聽= 0.97-1.14) or the prone position (RR = 1.01, 95%CI = 0.88-1.15).
Conclusions
Compared with supine whole-breast irradiation, prone breast irradiation is associated with a significantly lower predicted risk of secondary lung malignancy. In this modeling study, fractionation schedule did not have an impact on the risk of SLMs in women treated with whole-breast RT for early breast cancer.