Miyakojima IGRT Clinic, Osaka, Japan.
Strahlenther Onkol. 2011 Feb;187(2):108-13. doi: 10.1007/s00066-010-2187-1. Epub 2011 Jan 21.
To perform aggressive radiotherapy for vertebral metastases. Using very steep dose gradients from intensity-modulated radiotherapy (IMRT), a protocol based on the concept of partial volume dose to the spinal cord was evaluated.
50 patients with vertebral metastases were treated using IMRT. In previously unirradiated cases, where a prescribed dose of 80 Gy (BED10) was delivered, the constraint to the spinal cord should be less than 100 Gy (BED2). For previously irradiated cases, on the other hand, the dose is the same as in the previously unirradiated case; however, constraints for the spinal cord are a cumulative BED2 of less than 150 Gy, BED2 of less than 100 Gy in each instance, and a treatment gap of more than 6 months. There were 6 patients considered for a partial volume dose to the spinal cord. They all received higher BED2, ranging from 51-157 Gy of D1cc.
Among the 24 patients who survived longer than 1 year, there was 1 case of transient radiation myelitis. There were no other cases of spinal cord sequelae.
Based on the present results, we recommend a BED2 of 100 Gy or less at D1cc as a constraint for the spinal cord in previously unirradiated cases, and a cumulative BED2 of 150 Gy or less at D1cc in previously irradiated cases, when the interval was not shorter than 6 months and the BED2 for each session was 100 Gy or less. The prescribed BED10 of 80 Gy could be safely delivered to the vertebral lesions.
对椎体转移进行积极的放射治疗。采用强度调制放射治疗（IMRT）的陡峭剂量梯度，评估了一种基于脊髓部分容积剂量概念的方案。
对 50 例椎体转移患者进行 IMRT 治疗。在未接受过放疗的病例中，当给予 80 Gy（BED10）的处方剂量时，脊髓的限制应小于 100 Gy（BED2）。另一方面，对于已接受过放疗的病例，剂量与未接受过放疗的病例相同；然而，脊髓的限制条件是累积 BED2 小于 150 Gy，每次 BED2 小于 100 Gy，且治疗间隔大于 6 个月。有 6 例患者被认为需要脊髓部分容积剂量。他们都接受了更高的 BED2，D1cc 范围从 51-157 Gy。
在存活时间超过 1 年的 24 例患者中，有 1 例出现短暂性放射性脊髓炎。没有其他脊髓后遗症病例。
基于目前的结果，我们建议在未接受过放疗的病例中，将 D1cc 处脊髓的 BED2 限制在 100 Gy 或以下，在间隔时间不少于 6 个月且每次 BED2 限制在 100 Gy 或以下的情况下，将累积 BED2 限制在 150 Gy 或以下，当间隔时间不少于 6 个月且 BED2 每次为 100 Gy 或以下时，可以安全地将处方 BED10 的 80 Gy 用于椎体病变。
