Whole-brain irradiation with simultaneous integrated boost by helical tomotherapy for multiple brain metastases:dosimetric and clinical analyses
Ma Yuchao, Xiao Jianping, Bi Nan, Xu Yingjie, Tian Yuan, Zhang Hongmei, Zhang Ye, Liu Qingfeng, Deng Lei, Wang Wenqing, Zhao Ruizhi, Yang Siran, Yi Junlin, Li Yexiong
Department of Radiation Oncology,National Cancer Center/Cancer Hospital,Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing 100021,China
Abstract：Objective To retrospectively analyze the dosimetry and efficacy of whole-brain irradiation (WBRT) with simultaneous integrated boost (SIB) by helical tomotherapy (HT) in the treatment of multiple brain metastases (BMs), and to evaluate the feasibility, efficacy, and safety of HT. Methods From 2014 to 2017, a total of 43 patients with multiple BMs (no less than 3 lesions) were enrolled as subjects. A dose of 40 Gy was delivered to the whole brain in 20 fractions, while a dose of 60 Gy was delivered to the gross target volume (GTV) in 20 fractions. Patients were reexamined by magnetic resonance imaging during treatment. The radiation field would be shrunk if GTV was reduced. Target coverage (TC), conformity index (CI), prescription isodose/target volume (PITV) ratio , and homogeneity index (HI) were assessed. Clinical indices included local recurrence-free survival (LRFS), intracranial progression-free survival (IPFS), progression-free survival (PFS), overall survival (OS), and toxicities. Results The median lesion number was 6(3-36) and the median total volume of GTV was 8.74 cm3. The TC, CI, PITV, and HI for GTV were 0.96±0.028, 0.51±0.164, 2.09±1.245, and 0.12±0.066, respectively, while the TC and HI for the whole brain were 0.95±0.033 and 0.43±0.161, respectively. In all the patients, 26% had replanning during treatment. The two-stage treatment reduced the radiation dose to organs at risk. The 1-year LRFS, IPFS, PFS, and OS rates were 96%, 80%, 39%, and 86%, respectively. No grade ≥3 toxicities were observed. Conclusions WBRT with SIB by HT achieves satisfactory conformity, homogeneity, efficacy, and safety, which is a recommended treatment plan for multiple BMs. Replanning during treatment can better protect normal tissue.
Ma Yuchao,Xiao Jianping,Bi Nan et al. Whole-brain irradiation with simultaneous integrated boost by helical tomotherapy for multiple brain metastases:dosimetric and clinical analyses[J]. Chinese Journal of Radiation Oncology, 2018, 27(5): 435-440.
[1]Aoyama H,Shirato H,Tago M,et al. Stereotactic radiosurgery plus whole-brain radiation therapy vs. stereotactic radiosurgery alone for treatment of brain metastases:a randomized controlled trial[J].J Am Med Assoc,2006,295(21):2483-2491.DOI:10.1001/jama.295.21.2483. [2]Chang EL,Wefel JS,Hess KR,et al. Neurocognition in patients with brain metastases treated with radiosurgery or radiosurgery plus whole-brain irradiation:a randomised controlled trial[J].Lancet Oncol,2009,10(11):1037-1044.DOI:10.1016/S1470-2045(09)70263-3. [3]Chang WS,Kim HY,Chang JW,et al. Analysis of radiosurgical results in patients with brain metastases according to the number of brain lesions:is stereotactic radiosurgery effective for multiple brain metastases?[J].J Neurosurg,2010,113(Suppl):73-78.DOI:10.3171/2010.8GKS10994. [4]Damodar P,Sumit S,Christopher MC,et al. Treatment planning strategy for whole-brain radiotherapy with hippocampal sparing and simultaneous integrated boost for multiple brain metastases using intensity-modulated arc therapy[J].Med Dosim,2016,41(4):315–322.DOI:10.1016/j.meddos.2016.08.001. [5]Paolo B,Sara P,Luigi S,et al. Whole brain radiotherapy with adjuvant or concomitant boost in brain metastasis:dosimetric comparison between helical and volumetric IMRT technique[J].Radiat Oncol,2016,11(1):1-10.DOI:10.1186/s13014-016-0634-6. [6]Kim HK,Byoung CC,Chang GL,et al. Hippocampus-sparing whole-brain radiotherapy and simultaneous integrated boost for multiple brain metastases from lung adenocarcinoma:early response and dosimetric evaluation[J].Technol Cancer Res Treat,2016,15(1):122-129.DOI:10.1177/1533034614566993. [7]Gutierrez AN,Westerly DC,Tome WA,et al. Whole-brain radiotherapy with hippocampal avoidance and simultaneously integrated brain metastases boost:A planning study[J].Int J Radiat Oncol Biol Phys,2007,69(2):589-597.DOI:10.1016/j.ijrobp.2007.05.038. [8]Mackie TR,Holmes T,Swerdloff S,et al. Tomotherapy:A new concept for the delivery of dynamic conformal radiotherapy[J].Med Phys,1993,20(6):1709-1719.DOI:10.1118/1.596958. [9]Natsuo T,Takeshi K,Hiroyuki T,et al. Helical tomotherapy for brain metastases:dosimetric evaluation of treatment plans and early clinical results[J].Technol Cancer Res Treat,2008,7(6):417-424.DOI:10.1177/153303460800700602. [10]Rodrigues G,Yartsev S,Yaremko B,et al. Phase I trial of simultaneous in-field boost with helical tomotherapy for patients with one to three brain metastases[J].Int J Radiat Oncol Biol Phys,2011,92(4):1128-1133.DOI:10.1016/j.ijrobp.2010.03.047. [11]George R,Slav Y,Keng YT,et al. A phase Ⅱ multi-institutional study assessing simultaneous in-field boost helical tomotherapy for 1-3 brain metastases[J].Radiat Oncol,2012,7(1):42-50.DOI:10.1186/1748-717X-7-42. [12]Riet VA,Mak AC,Moerland MA,et al. A conformation number to quantify the degree of conformality in brachytherapy and external beam irradiation:application to the prostate[J].Int J Radiat Oncol Biol Phys,1997,37(3):731-736.DOI:10.1016/S0360-3016(96)00601-3. [13]International Commission on Radiation Units and Measurements,ICRU report 83:Prescribing,recording,and reporting photon-beam intensity-modulated radiation therapy (IMRT).J ICRU 2010;10:34-36. [14]Sabine L,Christoph P,Andrea W,et al. Helical tomotherapy for whole-brain irradiation with integrated boost to multiple brain metastases:evaluation of dose distribution characteristics and comparison with alternative techniques[J].Int J Radiat Oncol Biol Phys,2013,86(4):734-742.DOI:10.1016/j.ijrobp.2013.03.031.
2018, Vol. 27 
