Uder Laura, Nachbar Marcel, Butzer Sarah, Boldt Jessica, Baumeister Sabrina, Bitzer Michael, Königsrainer Alfred, Seufferlein Thomas, Hoffmann Rüdiger, Gatidis Sergios, Nikolaou Konstantin, Zips Daniel, Thorwarth Daniela, Gani Cihan, Boeke Simon
Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany.
Section for Biomedical Physics, Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany.
Front Oncol. 2023 Jan 16;12:1095633. doi: 10.3389/fonc.2022.1095633. eCollection 2022.
Stereotactic body radiotherapy (SBRT) is used to treat liver metastases with the intention of ablation. High local control rates were shown. Magnetic resonance imaging guided radiotherapy (MRgRT) provides the opportunity of a marker-less liver SBRT treatment due to the high soft tissue contrast. We report herein on one of the largest cohorts of patients treated with online MRgRT of liver metastases focusing on oncological outcome, toxicity, patient reported outcome measures (PROMs), quality of life.
Patients treated for liver metastases with online MR-guided SBRT at a 1,5 T MR-Linac (Unity, Elekta, Crawley, UK) between March 2019 and December 2021 were included in this prospective study. UK SABR guidelines were used for organs at risk constraints. Oncological endpoints such as survival parameters (overall survival, progression-free survival) and local control as well as patient reported acceptance and quality of life data (EORTC QLQ-C30 questionnaire) were assessed. For toxicity scoring the Common Toxicity Criteria Version 5 were used.
A total of 51 patients with 74 metastases were treated with a median of five fractions. The median applied BED GTV D98 was 84,1 Gy. Median follow-up was 15 months. Local control of the irradiated liver metastasis after 12 months was 89,6%, local control of the liver was 40,3%. Overall survival (OS) after 12 months was 85.1%. Progression free survival (PFS) after 12 months was 22,4%. Local control of the irradiated liver lesion was 100% after three years when a BED ≥100 Gy was reached. The number of treated lesions did not impact local control neither of the treated or of the hepatic control. Patient acceptance of online MRgSBRT was high. There were no acute grade ≥ 3 toxicities. Quality of life data showed no significant difference comparing baseline and follow-up data.
Online MR guided radiotherapy is a noninvasive, well-tolerated and effective treatment for liver metastases. Further prospective trials with the goal to define patients who actually benefit most from an online adaptive workflow are currently ongoing.
立体定向体部放疗（SBRT）用于以消融目的治疗肝转移瘤。已显示出较高的局部控制率。磁共振成像引导放疗（MRgRT）由于软组织对比度高，为无标记肝脏SBRT治疗提供了机会。我们在此报告接受肝脏转移瘤在线MRgRT治疗的最大患者队列之一，重点关注肿瘤学结局、毒性、患者报告结局指标（PROMs）和生活质量。
2019年3月至2021年12月期间在1.5T MR直线加速器（Unity，医科达，克劳利，英国）接受在线MR引导SBRT治疗肝转移瘤的患者纳入本前瞻性研究。英国SABR指南用于风险器官限制。评估生存参数（总生存期、无进展生存期）和局部控制等肿瘤学终点以及患者报告的接受度和生活质量数据（EORTC QLQ-C30问卷）。毒性评分采用《常见毒性标准》第5版。
共51例患者的74个转移瘤接受了中位5次分割治疗。应用的中位生物等效剂量（BED）GTV D98为84.1Gy。中位随访时间为15个月。12个月时照射的肝转移瘤局部控制率为89.6%，肝脏局部控制率为40.3%。12个月时总生存期（OS）为85.1%。12个月时无进展生存期（PFS）为22.4%。当达到BED≥100Gy时，三年后照射的肝脏病变局部控制率为100%。治疗的病变数量对治疗的或肝脏控制的局部控制均无影响。患者对在线MRgSBRT的接受度较高。无急性3级及以上毒性反应。生活质量数据显示基线和随访数据无显著差异。
在线MR引导放疗是一种治疗肝转移瘤的无创、耐受性良好且有效的治疗方法。目前正在进行进一步的前瞻性试验，目标是确定真正从在线适应性工作流程中获益最大的患者。
