Baines Imaging Research Laboratory, London, Ontario, Canada; Lawson Health Research Institute, London, Ontario, Canada; Department of Medical Biophysics, Western University, London, Ontario, Canada; London Regional Cancer Program, London, Ontario, Canada.
Department of Medical Biophysics, Western University, London, Ontario, Canada.
Brachytherapy. 2022 Jul-Aug;21(4):435-441. doi: 10.1016/j.brachy.2022.01.009. Epub 2022 Mar 22.
Multiparametric magnetic resonance imaging (mpMRI) has demonstrated the ability to localize intraprostatic lesions. It is our goal to determine how to optimally target the underlying histopathological cancer within the setting of high-dose-rate brachytherapy (HDR-BT).
Ten prostatectomy patients had pathologist-annotated mid-gland histology registered to pre-procedural mpMRI, which were interpreted by four different observers. Simulated HDR-BT plans with realistic catheter placements were generated by registering the mpMRI lesions and corresponding histology annotations to previously performed clinical HDR-BT implants. Inverse treatment planning was used to generate treatment plans that treated the entire gland to a single dose of 15 Gy, as well as focally targeted plans that aimed to escalate dose to the mpMRI lesions to 20.25 Gy. Three margins to the lesion were explored: 0 mm, 1 mm, and 2 mm. The analysis compared the dose that would have been delivered to the corresponding histologically-defined cancer with the different treatment planning techniques.
mpMRI-targeted plans delivered a significantly higher dose to the histologically-defined cancer (p < 0.001), in comparison to the standard treatment plans. Additionally, adding a 1 mm margin resulted in significantly higher D98, and D90 to the histologically-defined cancer in comparison to the 0 mm margin targeted plans (p = 0.019 & p = 0.0026). There was no significant difference between plans using 1 mm and 2 mm margins.
Adding a 1 mm margin to intraprostatic mpMRI lesions significantly increased the dose to histologically-defined cancer, in comparison applying no margin. No significant effect was observed by further expanding the margins.
多参数磁共振成像（mpMRI）已证明能够定位前列腺内病变。我们的目标是确定如何在高剂量率近距离放射治疗（HDR-BT）的背景下优化靶向潜在的组织病理学癌症。
10 名前列腺切除术患者的病理学家标记的中叶组织学与术前 mpMRI 进行了配准，由四位不同的观察者进行了解读。通过将 mpMRI 病变和相应的组织学注释配准到先前进行的临床 HDR-BT 植入物，生成具有逼真导管放置的模拟 HDR-BT 计划。逆向治疗计划用于生成治疗计划，将整个腺体治疗为单一剂量 15 Gy，以及针对 mpMRI 病变的焦点靶向计划，以将剂量提升至 20.25 Gy。探索了病变的三个边界：0 毫米、1 毫米和 2 毫米。该分析比较了不同治疗计划技术下将传递到相应组织学定义的癌症的剂量。
与标准治疗计划相比，mpMRI 靶向计划向组织学定义的癌症提供了显着更高的剂量（p < 0.001）。此外，与 0 毫米边界靶向计划相比，添加 1 毫米边界会导致向组织学定义的癌症的 D98 和 D90 显着增加（p=0.019 和 p=0.0026）。使用 1 毫米和 2 毫米边界的计划之间没有显着差异。
与不施加边界相比，向前列腺内 mpMRI 病变添加 1 毫米边界会显着增加向组织学定义的癌症的剂量。进一步扩大边界没有观察到明显的效果。
