Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy.
Department of Experimental Oncology, European Institute of Oncology, IRCCS, Milan, Italy.
Neuro Oncol. 2020 Sep 29;22(9):1348-1358. doi: 10.1093/neuonc/noaa067.
The aim of this study is to evaluate results in terms of local control (LC), overall survival (OS), and toxicity profile and to better identify factors influencing clinical outcome of skull base chordoma treated with proton therapy (PT) and carbon ion radiotherapy (CIRT).
We prospectively collected and analyzed data of 135 patients treated between November 2011 and December 2018. Total prescription dose in the PT group (70 patients) and CIRT group (65 patients) was 74 Gy relative biological effectiveness (RBE) delivered in 37 fractions and 70.4 Gy(RBE) delivered in 16 fractions, respectively (CIRT in unfavorable patients). LC and OS were evaluated using the Kaplan-Meier method. Univariate and multivariate analyses were performed, to identify prognostic factors on clinical outcomes.
After a median follow-up of 44 (range, 6-87) months, 14 (21%) and 8 (11%) local failures were observed in CIRT and PT group, respectively. Five-year LC rate was 71% in CIRT cohort and 84% in PT cohort. The estimated 5-year OS rate in the CIRT and PT group was 82% and 83%, respectively. On multivariate analysis, gross tumor volume (GTV), optic pathways, and/or brainstem compression and dose coverage are independent prognostic factors of local failure risk. High rate toxicity grade ≥3 was reported in 11% of patients.
Particle radiotherapy is an effective treatment for skull base chordoma with acceptable late toxicity. GTV, optic pathways, and/or brainstem compression and target coverage were independent prognostic factors for LC.
• Proton and carbon ion therapy are effective and safe in skull base chordoma.• Prognostic factors are GTV, organs at risk compression, and dose coverage.• Dual particle therapy and customized strategy was adopted.
本研究旨在评估质子治疗（PT）和碳离子放疗（CIRT）治疗颅底脊索瘤的局部控制（LC）、总生存（OS）和毒性概况，并更好地确定影响临床结果的因素。
我们前瞻性收集并分析了 2011 年 11 月至 2018 年 12 月期间治疗的 135 例患者的数据。PT 组（70 例）和 CIRT 组（65 例）的总处方剂量分别为 74 Gy 相对生物效应（RBE）分 37 次给予和 70.4 Gy（RBE）分 16 次给予（CIRT 用于预后不良的患者）。采用 Kaplan-Meier 法评估 LC 和 OS。进行单因素和多因素分析，以确定临床结局的预后因素。
中位随访 44（范围 6-87）个月后，CIRT 组和 PT 组分别观察到 14（21%）和 8（11%）例局部失败。CIRT 队列的 5 年 LC 率为 71%，PT 队列为 84%。CIRT 和 PT 组的估计 5 年 OS 率分别为 82%和 83%。多因素分析显示，肿瘤总体积（GTV）、视神经通路和/或脑干受压和剂量覆盖是局部失败风险的独立预后因素。报告有 11%的患者出现≥3 级高发生率毒性。
粒子放疗是治疗颅底脊索瘤的有效方法，其晚期毒性可接受。GTV、视神经通路和/或脑干受压和靶区覆盖是 LC 的独立预后因素。
