Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom.
Int J Radiat Oncol Biol Phys. 2012 Dec 1;84(5):e571-6. doi: 10.1016/j.ijrobp.2012.06.049. Epub 2012 Sep 11.
To define the safely tolerated doses to organs at risk (OARs) adjacent to the target volume (TV) of spine radiosurgery (SRS) with 18-Gy in a single fraction.
A total of 124 patient cases with 165 spine metastases were reviewed. An 18-Gy single-fraction regimen was prescribed to the 90% isodose line encompassing the TV. A constraint of 10 Gy to 10% of the spinal cord outlined 6 mm above and below the TV was used. Dosimetric data to OARs were analyzed.
A total of 124 patients (100%) were followed-up, and median follow-up time was 7 months (1-50 months). Symptoms and local control were achieved in 114 patients (92%). Acute Radiation Therapy Oncology Group (RTOG) grade 1 oral mucositis occurred in 11 of 11 (100%) patients at risk for oropharyngeal toxicity after cervical spine treatment. There were no RTOG grade 2-4 acute or late complications. Median TV was 43.2 cc (5.3-175.4 cc) and 90% of the TV received median dose of 19 Gy (17-19.8 Gy). Median (range) of spinal cord maximum dose (Dmax), dose to spinal cord 0.35 cc (Dsc0.35), and cord volume receiving 10 Gy (Vsc10) were 13.8 Gy (5.4-21 Gy), 8.9 Gy (2.6-11.4 Gy) and 0.33 cc (0-1.6 cc), respectively. Other OARs were evaluated when in proximity to the TV. Esophagus (n=58), trachea (n=28), oropharynx (n=11), and kidneys (n=34) received median (range) V10 and V15 of 3.1 cc (0-5.8 cc) and 1.2 cc (0-2.9 cc), 2.8 cc (0-4.9 cc), and 0.8 cc (0-2.1 cc), 3.4 cc (0-6.2 cc) and 1.6 cc (0-3.2 cc), 0.3 cc (0-0.8 cc) and 0.08 cc (0-0.1 cc), respectively.
Cord Dmax of 14 Gy and D0.35 of 10 Gy are safe dose constraints for 18-Gy single-fraction SRS. Esophagus V10 of 3 cc and V15 of 1 cc, trachea V10 of 3 cc, and V15 of 1 cc, oropharynx V10 of 3.5 cc and V15 of 1.5 cc, kidney V10 of 0.3 cc, and V15 of 0.1 cc are planning guidelines when these OARs are in proximity to the TV.
在单次 18Gy 分割中，确定与脊柱放射外科（SRS）靶区（TV）相邻的危及器官（OAR）的安全耐受剂量。
共回顾了 124 例 165 个脊柱转移瘤患者的病例。将 18Gy 的单剂量方案规定为包含 TV 的 90%等剂量线。使用限制脊髓 10Gy 至 TV 上下 6mm 内的 10%脊髓体积（Vsc0.35）的约束条件。对 OAR 的剂量学数据进行了分析。
124 例患者（100%）接受了随访，中位随访时间为 7 个月（1-50 个月）。114 例患者（92%）实现了症状缓解和局部控制。在接受颈椎治疗的咽后毒性风险的 11 例患者中（11/11，100%）发生了急性放射治疗肿瘤协作组（RTOG）1 级口腔黏膜炎。无 RTOG 2-4 级急性或迟发性并发症。中位 TV 为 43.2cc（5.3-175.4cc），90%的 TV 接受了中位剂量 19Gy（17-19.8Gy）。脊髓最大剂量（Dmax）、脊髓 0.35cc 剂量（Dsc0.35）和接受 10Gy 的脊髓体积（Vsc10）的中位数（范围）分别为 13.8Gy（5.4-21Gy）、8.9Gy（2.6-11.4Gy）和 0.33cc（0-1.6cc）。当 OAR 接近 TV 时，对其他 OAR 进行了评估。食管（n=58）、气管（n=28）、口咽（n=11）和肾脏（n=34）的 V10 和 V15 的中位数（范围）分别为 3.1cc（0-5.8cc）和 1.2cc（0-2.9cc）、2.8cc（0-4.9cc）和 0.8cc（0-2.1cc）、3.4cc（0-6.2cc）和 1.6cc（0-3.2cc）、0.3cc（0-0.8cc）和 0.08cc（0-0.1cc）。
脊髓 Dmax 为 14Gy 和 D0.35 为 10Gy 是 18Gy 单次 SRS 的安全剂量限制。当 OAR 接近 TV 时，食管 V10 为 3cc，V15 为 1cc，气管 V10 为 3cc，V15 为 1cc，口咽 V10 为 3.5cc，V15 为 1.5cc，肾脏 V10 为 0.3cc，V15 为 0.1cc，可作为规划指南。
