Zayed Sondos, Ruschin Mark, Atenafu Eshetu G, Chen Hanbo, Dinakaran Deepak, Detsky Jay, Myrehaug Sten, Soliman Hany, Witiw Christopher, Larouche Jeremie, Maralani Pejman, Sahgal Arjun, Tseng Chia-Lin
Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
Division of Radiation Oncology, Department of Radiology, Radiation Oncology, Medical Physics, The Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada.
J Neurooncol. 2025 Jul 16. doi: 10.1007/s11060-025-05157-z.
The relationship between spine SBRT outcomes and the extent of epidural cauda equina compression (ECEC) by malignant epidural disease has yet to be reported. Our objective was to determine clinical, anatomic and dosimetric factors that predict for local failure (LF) and overall survival (OS) specific to ECEC.
Consecutive patients with ECEC treated with spine SBRT were retrospectively reviewed. ECEC parameters including anatomic measurements, lumbar stenosis grading, anatomic disease position and various dosimetric factors, were analyzed for their prognostic utility. Covariates with a p-value ≤ 0.20 on univariate analysis were selected for multivariable analysis (MVA), and those statistically significant (p < 0.05) were included in the final model.
Ninety-four spinal segments (79 patients) with ECEC were identified, 69 (73%) were intact (non-operated) and 25 (27%) post-operative. MVA identified a significantly lower risk of LF with systemic-therapy prior to SBRT (HR 0.164, p = 0.0005), ECEC encompassing ≤ 1/3 of the circumference of the spinal canal (HR 0.216, p = 0.0194) and an epidural disease volume < 0.45cm (HR 0.000, p < 0.001). In the intact cohort, a greater volume of epidural disease receiving 50 Gy (V50Gy) as an Equivalent Dose in 2 Gy Fractions (EQD2) using an α/β = 10 was associated with a lower LF (HR 0.909, p = 0.0122). Oligometastatic disease and ECEC limited to a single spinal-level were significant prognostic factors for OS in both cohorts.
The volume and circumferential extent of epidural disease within the spinal canal are important factors for LF in ECEC treated by SBRT, suggesting a possible therapeutic role for surgical cytoreduction to enable optimal treatment planning.
脊柱立体定向放射治疗（SBRT）的疗效与恶性硬膜外疾病导致的硬膜外马尾神经受压（ECEC）程度之间的关系尚未见报道。我们的目的是确定预测ECEC局部失败（LF）和总生存期（OS）的临床、解剖学和剂量学因素。
对接受脊柱SBRT治疗的连续性ECEC患者进行回顾性分析。分析ECEC参数，包括解剖学测量、腰椎管狭窄分级、解剖学疾病位置和各种剂量学因素，以评估其预后价值。单因素分析中p值≤0.20的协变量被选入多因素分析（MVA），具有统计学意义（p<0.05）的因素被纳入最终模型。
共确定94个存在ECEC的脊柱节段（79例患者），其中69个（73%）完整（未手术），25个（27%）为术后患者。MVA结果显示，SBRT前接受全身治疗的患者LF风险显著降低（风险比[HR]0.164，p=0.0005），ECEC累及椎管周长≤1/3的患者LF风险降低（HR 0.216，p=0.0194），硬膜外疾病体积<0.45cm的患者LF风险降低（HR 0.000，p<0.001）。在完整队列中，以α/β=10将接受50 Gy等效剂量（以2 Gy分次计算的等效剂量[EQD2]）的更大体积硬膜外疾病定义为V50Gy，其与较低的LF相关（HR 0.909，p=0.0122）。寡转移疾病和局限于单个脊柱节段的ECEC是两个队列OS的重要预后因素。
椎管内硬膜外疾病的体积和周向范围是SBRT治疗ECEC时LF的重要因素，提示手术减瘤在实现最佳治疗计划方面可能具有治疗作用。
