CRUK Clinical Trials Unit, University of Glasgow, Glasgow, UK; Beatson West of Scotland Cancer Centre, Glasgow, UK.
University of Leeds, Leeds, UK; Leeds Teaching Hospitals NHS Trust, Leeds, UK.
Clin Oncol (R Coll Radiol). 2021 Apr;33(4):214-223. doi: 10.1016/j.clon.2020.12.011. Epub 2021 Jan 8.
Preoperative (chemo)radiotherapy followed by total mesorectal excision is the current standard of care for patients with locally advanced rectal cancer. The use of intensity-modulated radiotherapy (IMRT) for rectal cancer is increasing in the UK. However, the extent of IMRT implementation and current practice was not previously known. A national survey was commissioned to investigate the landscape of IMRT use for rectal cancer and to inform the development of national rectal cancer IMRT guidance.
A web-based survey was developed by the National Rectal Cancer IMRT Guidance working group in collaboration with the Royal College of Radiologists and disseminated to all UK radiotherapy centres. The survey enquired about the implementation of IMRT with a focus on the following aspects of the workflow: dose fractionation schedules and use of a boost; pre-treatment preparation and simulation; target volume/organ at risk definition; treatment planning and treatment verification. A descriptive statistical analysis was carried out.
In total, 44 of 63 centres (70%) responded to the survey; 30/44 (68%) and 36/44 (82%) centres currently use IMRT to treat all patients and selected patients with rectal cancer, respectively. There was general agreement concerning several aspects of the IMRT workflow, including patient positioning, use of intravenous contrast and bladder protocols. Greater variation in practice was identified regarding rectal protocols; use of a boost to primary/nodal disease; target volume delineation; organ at risk delineation and dose constraints and treatment verification. Delineation of individual small bowel loops and daily volumetric treatment verification were considered potentially feasible by most centres.
This survey identified that IMRT is already used to treat rectal cancer in many UK radiotherapy centres, but there is heterogeneity between centres in its implementation and practice. These results have been a valuable aid in framing the recommendations within the new National Rectal Cancer IMRT Guidance.
术前（放化疗）联合全直肠系膜切除术是局部进展期直肠癌的标准治疗方法。在英国，强度调制放疗（IMRT）在直肠癌中的应用正在增加。然而，IMRT 的实施程度和当前的实践情况尚不清楚。为此，开展了一项全国性调查，以了解直肠癌 IMRT 的使用情况，并为制定全国直肠癌 IMRT 指南提供信息。
由国家直肠癌 IMRT 指南工作组与皇家放射科医师学院合作开发了一个基于网络的调查，并分发给所有英国放射治疗中心。该调查询问了 IMRT 的实施情况，重点关注工作流程的以下方面：剂量分割方案和使用增敏剂量；治疗前准备和模拟；靶区/危及器官定义；治疗计划和治疗验证。进行了描述性统计分析。
在总共 63 个中心中，有 44 个（70%）中心对调查做出了回应；其中 30/44（68%）和 36/44（82%）中心目前分别对所有和选择的直肠癌患者使用 IMRT 治疗。在 IMRT 工作流程的几个方面，包括患者定位、静脉内对比剂和膀胱方案的使用等方面，存在普遍共识。在直肠方案、原发/淋巴结疾病的增敏剂量使用、靶区勾画、危及器官勾画以及剂量限制和治疗验证等方面，实践中的差异更大。大多数中心认为勾画单个小肠环和每日容积治疗验证是可行的。
本调查发现，IMRT 已在英国许多放射治疗中心用于治疗直肠癌，但在其实施和实践方面存在中心间的异质性。这些结果为制定新的国家直肠癌 IMRT 指南中的建议提供了有价值的帮助。
