Radiation Oncology, Liverpool Cancer Therapy Centre, Sydney, New South Wales, Australia.
Radiation Oncology, Macarthur Cancer Therapy Centre, Sydney, New South Wales, Australia.
J Med Imaging Radiat Oncol. 2020 Jun;64(3):427-434. doi: 10.1111/1754-9485.13023. Epub 2020 Mar 31.
Protocols have been developed in our department with recommended dose constraints for organs at risk (OAR) for each tumour site receiving definitive radiotherapy. We have developed a colour coding system to indicate when constraints are meeting objectives (green), have minor variation from planning objectives (yellow) and have major variation from planning objectives (red). We performed a quality audit to assess adherence to the protocol and to determine the rate of acute and subacute toxicities.
All definitive radiotherapy dose-volume histogram (DVH) reports generated in the first 6 months of 2017 at Liverpool and Macarthur cancer therapy centres were collected. For each radiotherapy group, the overridden dose constraints were evaluated and categorized to red and yellow. For all patients in our data set, follow-up documents/assessments were searched for grade 3 or higher acute or subacute radiotherapy toxicity and compared with those who had overridden dose constraints.
There were 210 (34%) plans accepted with at least one major variation and 161 (26%) plans with minor variation. Head and neck group had the most rate of major variations (77%). The best groups in adherence to protocol were lymphoma and breast groups. In general, grade 3 toxicity was observed in 1%, 4% and 9% of patients who were in green, yellow and red categories. Overall, we noted a correlation with grade 3 toxicities between acceptable plans (green) and ones with a minor or major variation (yellow or red) (1% vs. 7% P = 0.0001).
In conclusion this study showed an increased risk of higher grade toxicities when DVHs were beyond our departmental constraints using a 'Traffic Light System'. With this new colour coding system, we can facilitate auditing of the dose constraints in order to improve the quality of radiotherapy plans and potentially provide benchmarking for reducing toxicities in radiotherapy treatments.
我们部门为每个接受根治性放疗的肿瘤部位的危及器官（OAR）制定了推荐剂量限制的方案。我们开发了一种颜色编码系统，用于指示限制是否符合目标（绿色）、与计划目标有较小差异（黄色）或与计划目标有较大差异（红色）。我们进行了质量审核，以评估对方案的遵守情况，并确定急性和亚急性毒性的发生率。
收集了 2017 年上半年在利物浦和麦卡瑟癌症治疗中心生成的所有根治性放疗剂量-体积直方图（DVH）报告。对于每个放疗组，评估并分类了超出限制的剂量限制，分为红色和黄色。在我们的数据集中的所有患者中，搜索随访文件/评估以寻找 3 级或更高的急性或亚急性放疗毒性，并与那些剂量限制被超出的患者进行比较。
有 210 份（34%）计划至少有一个主要差异被接受，有 161 份（26%）计划有较小差异。头颈部组的主要变化率最高（77%）。最遵守方案的组是淋巴瘤和乳腺癌组。一般来说，在处于绿色、黄色和红色类别的患者中，分别有 1%、4%和 9%观察到 3 级毒性。总体而言，我们注意到在可接受的计划（绿色）和有较小或较大差异的计划（黄色或红色）之间，3 级毒性之间存在相关性（1%比 7%，P=0.0001）。
总之，这项研究表明，当 DVH 超出我们部门的限制时，使用“红绿灯系统”会增加更高等级毒性的风险。通过这种新的颜色编码系统，我们可以方便地审核剂量限制，以提高放疗计划的质量，并有可能为减少放疗治疗中的毒性提供基准。
