Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
Radiother Oncol. 2018 Jul;128(1):139-146. doi: 10.1016/j.radonc.2018.02.024. Epub 2018 Mar 12.
To compare dose to organs at risk (OARs) and dose-escalation possibility for 24 stage I non-small cell lung cancer (NSCLC) patients in a ROCOCO (Radiation Oncology Collaborative Comparison) trial.
For each patient, 3 photon plans [Intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and CyberKnife], a double scattered proton (DSP) and an intensity-modulated carbon-ion (IMIT) therapy plan were created. Dose prescription was 60 Gy (equivalent) in 8 fractions.
The mean dose and dose to 2% of the clinical target volume (CTV) were lower for protons and ions compared with IMRT (p < 0.01). Doses to the lungs, heart, and mediastinal structures were lowest with IMIT (p < 0.01), doses to the spinal cord were lowest with DSP (p < 0.01). VMAT and CyberKnife allowed for reduced doses to most OARs compared with IMRT. Dose escalation was possible for 8 patients. Generally, the mediastinum was the primary dose-limiting organ.
On average, the doses to the OARs were lowest using particles, with more homogenous CTV doses. Given the ability of VMAT and CyberKnife to limit doses to OARs compared with IMRT, the additional benefit of particles may only be clinically relevant in selected patients and thus should be carefully weighed for every individual patient.
比较 24 例 I 期非小细胞肺癌（NSCLC）患者在 ROCOCO（放射肿瘤学协作比较）试验中风险器官（OARs）的剂量和剂量递增的可能性。
为每位患者创建了 3 种光子计划（调强放疗（IMRT）、容积调强弧形治疗（VMAT）和 CyberKnife）、双散射质子（DSP）和调强碳离子（IMIT）治疗计划。剂量处方为 60Gy（等效）分 8 次。
与 IMRT 相比，质子和离子的平均剂量和 2%临床靶体积（CTV）的剂量较低（p<0.01）。肺、心脏和纵隔结构的剂量最低，与 IMIT（p<0.01），脊髓的剂量最低与 DSP（p<0.01）。与 IMRT 相比，VMAT 和 CyberKnife 允许大多数 OAR 减少剂量。8 名患者可以进行剂量递增。通常，纵隔是主要的剂量限制器官。
平均而言，使用粒子时 OAR 的剂量最低，CTV 剂量更均匀。鉴于 VMAT 和 CyberKnife 与 IMRT 相比限制 OAR 剂量的能力，粒子的额外益处可能仅在某些患者中具有临床相关性，因此应仔细权衡每个患者的情况。
