在头颈癌（HNC）中，阳性切缘强烈预示着治疗失败的可能。我们试图通过使用数字三维模型基于传统解剖标记来测量边缘取样位点的定位精度。我们导入了在我 们机构手术治疗过的9名HNC患者的术前CT扫描，并使用多平面放射学软件渲染每个肿瘤的数字三维模型，旨在代表切除标本。手术过程中记录的切缘标签从病理记录中收集。这些标签（N=64）呈现给参与的医生。要求参与者在参考相应的放射学平面下，使用3D模型标记每个手术边缘的解剖位置。对于每个单独的边缘，使用每个参与者的标记的3D坐标来计算一个平均定位点，称为几何重心。比较了与参与者和切缘类型相关的每个标记到重心的平均距离。在7名外科医生中，平均距离为12.6mm（[标准差] = 7.5）从重心测量标记的位置。深部边缘的平均距离比粘膜/皮肤边缘的大（19.6 [24.8] mm vs. 15.3 [14.9] mm，p = 0.034）。当要求医生在重新切除时重新定位边缘时，医生将在平均距离为20.6 [12.4] mm的范围内标记重心位置，范围为3.9-45.1mm。回顾性地定位传统标记的边缘是一个不精确的过程，并且存在团队内的变异性。未来定位精度的干预措施目标是完善采样文档和沟通。版权所有©2023年Elsevier Ltd。

In head and neck cancer (HNC), positive margins are strongly predictive of treatment failure. We sought to measure the accuracy of localization of margin sampling sites based on conventional anatomic labels using a digital 3D-model.Preoperative CT scans for 9 patients with HNC treated operatively at our institution were imported into a multiplanar radiology software, which was used to render a digital 3D model of each tumor intended to represent the resection specimen. Surgical margin labels recorded during the operative case were collected from pathology records. Margin labels (N = 64) were presented to participating physicians.Participants were asked to mark the anatomic location of each surgical margin using the 3D-model and corresponding radiographic planes for reference.For each individual margin, the 3D coordinates of each participant's marker were used to calculate a mean localization point called the geometric centroid. Mean distance from individual markers to the centroid was compared between participantsand margin types.Amongst 7 surgeons, markers were placed a mean distance of 12.6 mm ([SD] = 7.5) from the centroid.Deep margins were marked with a greater mean distance than mucosal/skin margins (19.6 [24.8] mm vs. 15.3 [14.9] mm, p = 0.034). When asked to relocate a margin following re-resection, surgeons marked a point an average of 20.6 [12.4] mm from their first marker with a range of 3.9- 45.1 mm.Retrospective localization of conventionally labeled margins is an imprecise process with variability across the care team. Future interventions targeting margin documentation and communication may improve sampling precision.Copyright © 2023. Published by Elsevier Ltd.