BACKGROUND Several ablation confirmation software methods for minimum ablative margin assessment have recently been developed to improve local outcomes for patients undergoing thermal ablation of colorectal liver metastases. Previous assessments were limited to single institutions mostly at the place of development. The aim of this study was to validate the previously identified 5 mm minimum ablative margin (A0) using autosegmentation and biomechanical deformable image registration in a multi-institutional setting. METHODS This was a multicentre, retrospective study including patients with colorectal liver metastases undergoing CT- or ultrasound-guided microwave or radiofrequency ablation during 2009-2022, reporting 3-year local disease progression (residual unablated tumour or local tumour progression) rates by minimum ablative margin across all institutions and identifying an intraprocedural contrast-enhanced CT-based minimum ablative margin associated with a 3-year local disease progression rate of less than 1%. RESULTS A total of 400 ablated colorectal liver metastases (median diameter of 1.5 cm) in 243 patients (145 men; median age of 62 [interquartile range 54-70] years) were evaluated, with a median follow-up of 26 (interquartile range 17-40) months. A total of 119 (48.9%) patients with 186 (46.5%) colorectal liver metastases were from international institutions B, C, and D that were not involved in the software development. Three-year local disease progression rates for 0 mm, >0 and <5 mm, and 5 mm or larger minimum ablative margins were 79%, 15%, and 0% respectively for institution A (where the software was developed) and 34%, 19%, and 2% respectively for institutions B, C, and D combined. Local disease progression risk decreased to less than 1% with an intraprocedurally confirmed minimum ablative margin greater than 4.6 mm. CONCLUSION A minimum ablative margin of 5 mm or larger demonstrates optimal local oncological outcomes. It is proposed that an intraprocedural minimum ablative margin of 5 mm or larger, confirmed using biomechanical deformable image registration, serves as the A0 for colorectal liver metastasis thermal ablation.

中文翻译：

---

确定结直肠肝转移的 A0 最小消融切缘：使用可变形 CT 配准和基于人工智能的自动分割的多中心回顾性研究。


背景 最近开发了几种用于最小消融切缘评估的消融确认软件方法，以改善接受结直肠肝转移热消融患者的局部预后。以前的评估仅限于主要位于发展地的单一机构。本研究的目的是在多机构环境中使用自动分割和生物力学可变形图像配准来验证先前确定的 5 毫米最小烧蚀边缘 （A0）。方法 这是一项多中心回顾性研究，包括 2009-2022 年期间接受 CT 或超声引导下微波或射频消融术的结直肠肝转移患者，报告了所有机构的 3 年局部疾病进展率（残余未消融肿瘤或局部肿瘤进展）的最小消融切缘，并确定了与 3 年局部疾病进展率大于 1%。结果 共评估了 243 例患者 （145 名男性;中位年龄 62 [四分位距 54-70] 岁） 的 400 例消融结直肠肝转移 （中位直径为 1.5 cm），中位随访时间为 26 （四分位距 17-40） 个月。共有 119 例 （48.9%） 患者患有 186 例 （46.5%） 结直肠肝转移，这些患者来自未参与软件开发的国际机构 B、C 和 D。机构 A（开发软件的地方）的 0 mm、>0 和 <5 mm 以及 5 mm 或更大的最小消融切缘的三年局部疾病进展率分别为 79%、15% 和 0%，机构 B、C 和 D 合计分别为 34%、19% 和 2%。 局部疾病进展风险降至 1% 以下，术中确认的最小消融切缘大于 4.6 毫米。结论 最小消融切缘 5 mm 或更大表明最佳的局部肿瘤学结局。建议使用生物力学可变形图像配准确认 5 毫米或更大的术中最小消融切缘，作为结直肠肝转移热消融的 A0。