Segedin Barbara, Petric Primoz
Department of Radiation Oncology, Institute of Oncology Ljubljana, Slovenia.
Department of Radation Oncology, National Centre for Cancer Care and Research, Doha, Qatar.
Radiol Oncol. 2016 May 9;50(3):254-62. doi: 10.1515/raon-2016-0023. eCollection 2016 Sep 1.
Modern radiotherapy techniques enable delivery of high doses to the target volume without escalating dose to organs at risk, offering the possibility of better local control while preserving good quality of life. Uncertainties in target volume delineation have been demonstrated for most tumour sites, and various studies indicate that inconsistencies in target volume delineation may be larger than errors in all other steps of the treatment planning and delivery process. The aim of this paper is to summarize the degree of delineation uncertainties for different tumour sites reported in the literature and review the effect of strategies to minimize them.
Our review confirmed that interobserver variability in target volume contouring represents the largest uncertainty in the process for most tumour sites, potentially resulting in a systematic error in dose delivery, which could influence local control in individual patients. For most tumour sites the optimal combination of imaging modalities for target delineation still needs to be determined. Strict use of delineation guidelines and protocols is advisable both in every day clinical practice and in clinical studies to diminish interobserver variability. Continuing medical education of radiation oncologists cannot be overemphasized, intensive formal training on interpretation of sectional imaging should be included in the program for radiation oncology residents.
现代放疗技术能够在不增加危及器官剂量的情况下，向靶区输送高剂量射线，从而在保持良好生活质量的同时，实现更好的局部控制。多数肿瘤部位在靶区勾画方面都存在不确定性，多项研究表明，靶区勾画的不一致性可能比治疗计划和实施过程中其他所有步骤的误差都要大。本文旨在总结文献报道的不同肿瘤部位的勾画不确定性程度，并综述将其降至最低的策略的效果。
我们的综述证实，对于多数肿瘤部位，靶区轮廓勾画的观察者间差异是该过程中最大的不确定性，这可能导致剂量输送出现系统误差，进而影响个体患者的局部控制。对于多数肿瘤部位，仍需确定用于靶区勾画的最佳影像模态组合。在日常临床实践和临床研究中，建议严格使用勾画指南和方案，以减少观察者间差异。放射肿瘤学家的继续医学教育再怎么强调都不为过，放射肿瘤学住院医师培训项目应纳入针对断层影像解读的强化正规培训。
