Division of Medical Physics, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada.
Division of Medical Physics, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada.
Brachytherapy. 2022 Jul-Aug;21(4):405-414. doi: 10.1016/j.brachy.2022.03.003. Epub 2022 May 2.
To report on brachytherapy (BT) workflows for image-based treatments of locally advanced cervical cancer (CC) in Canada.
Medical Physicists in every Canadian cancer center were contacted and those with a CC-BT program were emailed a 44-item electronic questionnaire surveying workflow patterns including: fractionation schedules, prescription, equipment, imaging, and treatment delivery.
Of 47 centers contacted, all 34 who performed CC-BT participated in the survey. Brachytherapy boost, following external beam treatments, was delivered using high-dose-rate (HDR); one center also used pulsed-dose-rate. Intracavitary and/or interstitial treatments were done in 47% centers for 25-80% of their patients. All centers used image-based planning: CT (32%), CT planned with MRI for contouring (47%), MRI (18%), or cone beam CT (3%). For those performing volume-based planning (74%), the contours commonly included Clinical Target Volume (CTV)-High Risk (HR), CTV-Intermediate Risk, rectum, sigmoid, and bladder. The most common HDR dose-fractionation schedule was 7 [4.6 - 10] Gy in 4 [3 - 6] fractions with radiobiological dose prescriptions performed in 62% centers. Medical physics contribution was significant during most activities along the BT treatment pathway in all centers, especially in planning (88%), second checks (68%), and during treatment delivery (88%).
Compared to previous surveys, there is an increasing trend in the use of image-based volumetric planning, interstitial procedures, and radiobiological dose prescription. Cervical cancer brachytherapy in Canada is becoming more streamlined with the use of international practice guidelines. Involvement of medical physicists is vital to all stages of CC-BT, including program implementation, routine quality control, dosimetry, and treatment delivery.
报告加拿大基于图像的局部晚期宫颈癌（CC）近距离治疗的近距离治疗（BT）工作流程。
联系了每个加拿大癌症中心的医学物理学家，并向有 CC-BT 计划的人员发送了一份 44 项电子问卷，调查工作流程模式，包括：分次方案、处方、设备、成像和治疗传递。
在联系的 47 个中心中，所有进行 CC-BT 的 34 个中心都参与了调查。外照射治疗后，采用高剂量率（HDR）进行近距离治疗增强；一个中心还使用脉冲剂量率。47%的中心对 25-80%的患者进行腔内和/或间质治疗。所有中心都使用基于图像的计划：CT（32%）、CT 联合 MRI 进行轮廓勾画（47%）、MRI（18%）或锥形束 CT（3%）。对于那些进行基于体积的计划（74%）的中心，轮廓通常包括临床靶区（CTV）-高危（HR）、CTV-中危、直肠、乙状结肠和膀胱。最常见的 HDR 剂量分割方案是 7 [4.6-10] Gy，4 [3-6] 分次，62%的中心进行放射生物学剂量处方。在所有中心，医学物理学的贡献在 BT 治疗途径的大多数活动中都非常重要，尤其是在计划（88%）、二次检查（68%）和治疗传递（88%）期间。
与之前的调查相比，基于图像的体积计划、间质程序和放射生物学剂量处方的使用呈上升趋势。加拿大宫颈癌近距离治疗越来越符合国际实践指南。医学物理学家的参与对于 CC-BT 的所有阶段都至关重要，包括计划的实施、常规质量控制、剂量学和治疗传递。
