Abstract:Objective: To evaluate the dosimetric characteristics of axillary nodes with intensity modulated radiotherapy after breast conserving surgery. Methods: From November 2020 to November 2021, 16 consecutive left breast cancer patients were enrolled after breast conserving surgery. According to the ESTRO guidelines, the axillary level I and level II + interpectoral nodes were delineated. Four regimens are prepared: intensity-modulated radiotherapy based on tangential field for whole breast target (IMRT) or whole breast + axillary nodes target (IMRTn), volume modulated arc therapy for whole breast target (VMAT) or whole breast + axillary nodes target (VMATn). The prescription dose is 50 Gy per 25 fractions, and the relevant dosimetric parameters of each regimen are recorded. Results: The mean doses delivered to axillary nodes by IMRT and VMAT were (33.2±7.3) Gy and (32.6±7.4) Gy for level I (P = 0.477), (32.4±7.5) Gy and (30.2±7.8) Gy for level II + interpectoral nodes (P<0.001), respectively. The conformal index of IMRTn and IMRT were (0.698±0.05) and (0.753±0.03), (P = 0.001), (0.835±0.03) for VMATn and (0.857±0.04) for VMAT, (P = 0.018). The mean doses to ipsilateral lung by IMRT, IMRTn, VMATn were (10.3±1.2) Gy, (11.2±1.0) Gy and (10.5±0.8) Gy, respectively (P = 0.040). The V5 (volume receiving 5 Gy) to ipsilateral lung by IMRT, IMRTn, VMATn were (33.4±3.5)%, (38.5±3.7)% and (40.5±3.1)%, respectively (P<0.001). The mean doses to contralateral breast were (1.5±0.4) Gy, (1.7±0.7) Gy and (2.3±0.8) Gy, respectively (P = 0.006). Conclusion: The dose of axillary nodes was insufficient during whole breast radiotherapy. Whole breast + axillary area irradiation could deliver adequate prescription dose, and increase little dose to the normal tissues, but they were all lower than required dose constraints.
倪文婕, 王钦, 王秀楠, 侯栋梁, 孙保锦, 宋丽楠, 杨慧, 刘骁蕾, 张楠, 赵磊. 乳腺癌保乳术后调强放疗腋窝的剂量学研究[J]. 河北医学, 2022, 28(6): 930-933.
NI Wenjie, WANG Qin, WANG Xiunan, et al. Dosimetric Study of Intensity-Modulated Radiotherapy to the Axilla after Breast-Conserving Surgery for Breast Cancer. HeBei Med, 2022, 28(6): 930-933.
[1] Savolt A,Peley G,Polgar C,et al.Eight-year follow up result of the OTOASOR trial:the optimal treatment of the axilla - surgery or radiotherapy after positive sentinel lymph node biopsy in early-stage breast cancer:a randomized,single centre,phase III,non-inferiority trial[J].Eur Surg Oncol,2017,43(4):672-679. [2] Boyages J,Vicini F A,Shah C,et al.The risk of subclinical breast cancer-related lymphedema by the extent of axillary surgery and regional node irradiation:a randomized controlled trial[J].International Journal of Radiation Oncology Biology Physics,2021,109(4):987-997. [3] 中国医师协会放射肿瘤治疗医师分会.乳腺癌放射治疗指南(中国医师协会2020版)[J].中华放射肿瘤学杂志,2021,30(4):321-342. [4] Offersen B V,Boersma L J,Kirkove C,et al.ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer[J].Radiotherapy and Oncology,2015,114(1):3-10. [5] Duma M N.An update on regional nodal irradiation:indication,target volume delineation,and radiotherapy techniques[J].Breast Care,2020,15(2):128-135. [6] Novikov S N,Krzhivitskii P I,Melnik Y S,et al.Atlas of sentinel lymph nodes in early breast cancer using single-photon emission computed tomography:implication for lymphatic contouring[J].Radiation Oncology Journal,2021,39(1):8-14. [7] Zhang L,Yang Z,Chen X,et al.Dose coverage of axillary level I-III areas during whole breast irradiation with simplified intensity modulated radiation therapy in early stage breast cancer patients[J].Oncotarget,2015,6(20):18183-18191. [8] 彭冉,王淑莲,任雯廷,等.保乳术后腋窝淋巴结标准切线野与多野放疗的剂量学比较[J].中华放射肿瘤学杂志,2015,24(2):154-158. [9] Schmitt M,Pin Y,Pflumio C,et al.Incidental axillary dose delivery to axillary lymph node levels I–III by different techniques of whole-breast irradiation:a systematic literature review[J].Strahlentherapie und Onkologie,2021,197(9):820-828. [10] Jo I Y,Kim E S,Kim W C,et al.Dosimetric comparison of incidental axillary irradiation between three-dimensional conformal and volumetric modulated arc techniques for breast cancer[J].Molecular and clinical oncology,2020,12(6):551-556. [11] Jacobson G,Bunda-Randall N,Wen S,et al.Axillary lymph node coverage with 3-dimensional tangential field irradiation and correlation with heart and lung dose[J].Advances in Radiation Oncology,2017,2(4):630-635. [12] Wang S,Kirova Y M,Shan S C,et al.Different radiation techniques to deliver therapeutic dose to the axilla in patients with sentinel lymph node-positive breast cancer:Doses,techniques challenges and clinical considerations[J].Cancer/Radiotherapie,2018,22(8):767-772.