Chen Xuguang Scott, Zhang Lei, Ajithkumar Thankamma, Butala Anish A, Kim Michelle M, Mayo Charles, Rosen Benjamin S, Shen Colette J, Murray Louise
Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York.
Pract Radiat Oncol. 2025 Apr 23. doi: 10.1016/j.prro.2025.04.003.
An international workshop was convened by the Reirradiation Collaborative Group. We conducted a survey among the invited attendants to assess practice patterns of reirradiation for central nervous system tumors.
A web-based survey regarding central nervous system reirradiation was distributed to an international group of radiation oncologists and medical physicists via email.
Sixty-six respondents from 20 countries completed at least one section of the survey. The most important clinical considerations were treatment goal, degree of overlap, and cumulative dose. Among technical challenges, uncertainties in tolerance of organs at risk (OARs), tissue recovery factors (TRFs) and dose accumulation ranked the highest. Most respondents (68%) used a planning OAR volume with 0 to 3 mm margin. Highly conformal radiation techniques were preferred, including stereotactic body radiation therapy for spine (85%), intensity modulated radiation therapy for adult primary brain tumors (93%), and intensity modulated radiation therapy (100%) and proton therapy (83%) for pediatric cases. Most performed dose accumulation (65%) and evaluated cumulative biological (ie, equieffective) dose (88%). Sixty-one percent preferred rigid registration, whereas 35% used deformable registration, most commonly in pediatric cases (67%). The most frequently used α/β value for OARs was 2 Gy (76%). There was no clear consensus on OAR tolerance for any disease site. Different dose metrics were used for evaluation, including Dmax (48%) and D0.1cc (48%). Most (79%) considered time intervals between radiation courses. For adult primary brain tumors and brain metastasis, 50% and 46% recommended against reirradiation within a short interval (3-6 months). Most respondents (52%) used time dependent TRFs.
Among respondents, there are substantial variations in approaches to reirradiation (eg, addition of systemic therapy) and uncertainties in technical implementation (eg, OAR tolerance, TRF, and dose accumulation). Future collaborative registry-based and prospective studies should help address these uncertainties.
再照射协作组召开了一次国际研讨会。我们对受邀参会人员进行了一项调查，以评估中枢神经系统肿瘤再照射的实践模式。
通过电子邮件向国际放射肿瘤学家和医学物理学家群体发放了一份关于中枢神经系统再照射的网络调查问卷。
来自20个国家的66名受访者至少完成了调查问卷的一个部分。最重要的临床考虑因素是治疗目标、重叠程度和累积剂量。在技术挑战方面，危及器官（OAR）耐受性、组织恢复因子（TRF）和剂量累积的不确定性排名最高。大多数受访者（68%）使用边缘为0至3毫米的计划OAR体积。高度适形放疗技术更受青睐，包括脊柱立体定向体部放疗（85%）、成人原发性脑肿瘤调强放疗（93%）以及儿科病例调强放疗（100%）和质子治疗（83%）。大多数人进行剂量累积（65%）并评估累积生物（即等效）剂量（88%）。61%的人倾向于刚性配准，而35%的人使用可变形配准，最常用于儿科病例（67%）。OAR最常用的α/β值为2 Gy（76%）。对于任何疾病部位的OAR耐受性，均未达成明确共识。使用了不同的剂量指标进行评估，包括Dmax（48%）和D0.1cc（48%）。大多数人（79%）考虑了放疗疗程之间的时间间隔。对于成人原发性脑肿瘤和脑转移瘤，分别有50%和46%的人建议在短时间间隔（3至6个月）内不进行再照射。大多数受访者（52%）使用了时间依赖性TRF。
在受访者中，再照射方法（如联合全身治疗）存在很大差异，技术实施方面（如OAR耐受性、TRF和剂量累积）也存在不确定性。未来基于协作登记处的前瞻性研究应有助于解决这些不确定性问题。
