Dosimetric impact of deep inspiration breath-hold technique in postoperative radiotherapy for left-sided breast cancer
10.3760/cma.j.cn113030-20241102-00421
- VernacularTitle:深吸气屏气技术对左侧乳腺癌术后放疗的剂量学影响
- Author:
Duoduo WANG
1
;
Han GAO
1
;
Pudong QIAN
1
;
Yutao LI
1
;
Yingxin LIU
1
;
Zixuan NI
1
;
Yatian LIU
1
Author Information
1. 南京医科大学附属肿瘤医院/江苏省肿瘤医院/江苏省肿瘤防治研究所放疗科，南京 210009
- Publication Type:Journal Article
- Keywords:
Breast neoplasms, left-sided;
Deep inspiration breath-hold technique;
Doses to organs at risk;
Internal mammary lymph node irradiation
- From:
Chinese Journal of Radiation Oncology
2025;34(4):340-346
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the dosimetric advantages of deep inspiration breath-hold (DIBH) technique in postoperative radiotherapy for left-sided breast cancer.Methods:A prospective study was conducted on patients requiring adjuvant radiotherapy after left-sided breast cancer surgery at Jiangsu Cancer Hospital from January 2018 to May 2023. CT simulation images were acquired under both free breathing (FB) and DIBH respiratory modes. Planning target volumes (PTV) and organs at risk (OAR) were delineated, and dosimetric parameters were compared between the two respiratory modes. Additionally, patients were grouped into subgroups [internal mammary lymph node irradiation (IMNI) vs. non-IMNI, breast-conserving surgery (BCS) followed by radiotherapy vs. modified radical mastectomy (MRM) followed by radiotherapy], and dosimetric differences among subgroups for both breathing modes were compared. The Velocity system was used to measure the minimum distances from the heart and left anterior descending coronary artery (LAD) to the PTV surface on CT images. These distances were defined as the heart-to-PTV and LAD-to-PTV distances. Pearson correlation analysis was performed to assess the relationships between heart D max and LAD D max, heart-to-PTV distance and heart D mean, and LAD-to-PTV distance and LAD D max under both respiratory modes. Results:A total of 132 patients were included. Compared to the FB, DIBH showed no significant difference in target dose distribution, but significantly reduced dose to OAR. Specifically, the heart D mean and D max decreased by 1.8 Gy and 8.1 Gy, respectively, and the LAD D max decreased by 7.9 Gy, and the affected lung V 5 Gy and V 20 Gy were reduced by 6.4% and 2.5%, respectively (all P<0.05). All subgroups benefited from DIBH, with greater decrease of dose to OAR in the IMNI subgroup (compared with the non-IMNI subgroup) and the subgroup of MRM followed by radiotherapy (compared with the BCS followed by radiotherapy group). Under both FB and DIBH modes, heart D max and LAD D max showed linear correlations ( r=0.62 and 0.84, respectively; both P<0.001), heart-to-PTV distance correlated with heart D mean ( r=-0.61 and -0.67, respectively; both P<0.001), and LAD-to-PTV distance correlated with LAD D max ( r=-0.58 and -0.63, respectively; both P<0.001). Conclusions:The DIBH technique can significantly reduce dose to the heart, LAD, and lungs in patients undergoing postoperative radiotherapy for left-sided breast cancer without compromising target dose. Patients receiving IMNI after left-sided breast cancer surgery benefit more from the DIBH technique.
