Robotic stereotactic ablative radiotherapy (SABR) is currently under investigation as a noninvasive treatment option for patients with renal cell carcinoma (RCC). For radiation therapy of RCC, tumor motion and the need for high ablative doses while preserving the remaining renal parenchyma is a challenge. We aimed to analyze the safety and efficacy of robotic radiosurgery in RCC in a specific difficult subgroup of patients with impaired renal function. We retrospectively identified all patients with RCC, treated with robotic SABR and motion compensation in our institution between 2012 and 2017. Either single fraction SABR of 24 or 25 Gy or 3 fractions of 12 Gy prescribed to the 70% isodose line was applied. Local control, overall survival, radiation side effects were evaluated together with renal function and tumor motion. We analyzed data of 13 lesions treated in 10 patients with clear cell RCC and a mean age of 70.5 ± 13.6 years (range: 48–87). Prior to SABR, 8 patients underwent previous complete and/or partial nephrectomy, 7 patients presented with chronic kidney disease ≥ stage 3. The median of minimum, mean and maximum planning target volume doses were 23.2, 29.5 and 35.0 Gy for single fraction and 24.4, 42.5 and 51.4 Gy for the three fractions regime. Persistent local control by robotic SABR was achieved in 9 out of 10 patients (92.3% of all lesions) within a median follow-up period of 27 month (range: 15–54). One patient underwent nephrectomy due to progressive disease and sufficient renal function of the contralateral kidney. Renal function remained stable with a mean estimated glomerular filtration rate (eGFR) of 51.3 ± 19.7 ml/min at baseline and 51.6 ± 25.8 ml/min at follow-up. The largest respiratory-induced tumor motion was seen in superior-inferior direction, compensated by the CyberKnife with mean targeting errors of maximal 2.2 mm. Robotic SABR is technically feasible for the treatment of RCC in preexisting kidney disease with good local tumor control at about 2 years follow-up. Robotic SABR with motion tracking offers a valid treatment option for patients, who are at increased risk for progression to end-stage renal disease due to partial nephrectomy or ablative techniques.

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机器人立体定向消融放射治疗肾功能不全患者的肾细胞癌

机器人立体定向消融放射治疗（SABR）目前正在研究中，作为肾细胞癌（RCC）患者的非侵入性治疗选择。对于RCC的放射治疗，肿瘤运动以及需要高剂量的消融剂同时保留剩余的肾实质是一个挑战。我们旨在分析在肾功能受损的特定困难亚组中，RCC机器人放射外科手术的安全性和有效性。我们回顾性分析了2012年至2017年间在我院中接受机器人SABR和运动补偿治疗的所有RCC患者，应用了70％等剂量线规定的24或25 Gy的单份SABR或12 Gy的3份。评估局部控制，总体生存率，放射副作用以及肾功能和肿瘤运动。我们分析了10例具有透明细胞RCC且平均年龄为70.5±13.6岁（范围：48-87）的患者中治疗的13个病变的数据。在SABR之前，有8例患者接受了先前的完全和/或部分肾切除术，其中7例患有≥3期的慢性肾脏疾病。中，最小和最大计划目标体积剂量的中位数分别为23.2、29.5和35.0 Gy（单次）和24.4 ，三个分馏方案分别为42.5和51.4 Gy。在27个月的中位随访期（范围：15-54）中，每10例患者中有9例（占所有病灶的92.3％）实现了通过机器人SABR的持久性局部控制。一名患者由于进行性疾病和对侧肾脏的足够肾功能而接受了肾切除术。肾功能保持稳定，平均肾小球滤过率（eGFR）在基线时为51.3±19.7 ml / min，在基线时为51。随访时为6±25.8 ml / min。在上-下方向观察到最大的呼吸诱发的肿瘤运动，由射波刀补偿，平均靶向误差最大为2.2 mm。在大约2年的随访中，机器人SABR在治疗肾癌中具有良好的局部肿瘤控制性的技术上是可行的。具有运动跟踪功能的机器人SABR为由于部分肾切除术或消融技术而罹患晚期肾病的风险增加的患者提供了有效的治疗选择。在大约2年的随访中，机器人SABR在治疗肾癌中具有良好的局部肿瘤控制性方面在技术上是可行的。具有运动跟踪功能的机器人SABR为由于部分肾切除术或消融技术而罹患晚期肾病的风险增加的患者提供了有效的治疗选择。在大约2年的随访中，机器人SABR在治疗肾癌中具有良好的局部肿瘤控制性方面在技术上是可行的。具有运动跟踪功能的机器人SABR为由于部分肾切除术或消融技术而罹患晚期肾病的风险增加的患者提供了有效的治疗选择。