From the Departments of Radiology.
Surgery.
Invest Radiol. 2020 May;55(5):270-276. doi: 10.1097/RLI.0000000000000638.
Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a very low 5-year survival rate of 8%. The aims of this study are to determine reference values and physiologic confounders in healthy pancreas and to assess the diagnostic accuracy of ultrasound time-harmonic elastography (THE) in the detection of PDAC.
From March 2017 through May 2019, a total of 54 study participants with healthy pancreas (n = 33, CTR) or PDAC (n = 21) were prospectively enrolled. Repeatability of THE was tested in a CTR subgroup (n = 5) undergoing repeat measurement on 4 different days. Interobserver variability was analyzed in 10 healthy volunteers. Age-matched and sex-matched subgroups of CTR (n = 13) and PDAC (n = 13) were compared. In participants with histopathologically proven PDAC, measurements were performed separately in tumorous (PDAC-T) and nontumorous pancreatic tissue (PDAC-NT). Diagnostic performance of pancreatic THE was assessed by receiver operating characteristic curve analysis.
Time-harmonic elastography was highly repeatable (intraclass correlation coefficient, 0.99), and interobserver agreement was excellent (intraclass correlation coefficient, 0.97). Shear wave speed (SWS) of PDAC-T (mean [95% confidence interval] in meters per second, 1.88 ± 0.07 [1.84-1.92]) was higher than SWS of CTR (1.63 ± 0.04 [1.60-1.66], P < 0.001) and PDAC-NT (1.59 ± 0.03 [1.57-1.61], P < 0.001). The exploratory diagnostic performance of THE in separating PDAC-T was excellent (area under the receiver operating characteristic curve, 1.0). Tumorous pancreatic ductal adenocarcinoma was distinguished from CTR and PDAC-NT with cutoff values of 1.73 m/s and 1.70 m/s, respectively.
Pancreatic ultrasound THE has high repeatability and provides excellent imaging contrast based on SWS, allowing detection of PDAC without overlap to nontumorous pancreatic tissue.
胰腺导管腺癌（PDAC）是一种侵袭性很强的肿瘤，其 5 年生存率非常低，仅为 8%。本研究旨在确定健康胰腺的参考值和生理混杂因素，并评估超声谐波弹性成像（THE）在检测 PDAC 中的诊断准确性。
2017 年 3 月至 2019 年 5 月，共前瞻性纳入 54 名健康胰腺（n = 33，对照组）或 PDAC（n = 21）患者。在接受重复测量的对照组亚组（n = 5）中测试 THE 的重复性。在 10 名健康志愿者中分析了观察者间的变异性。对年龄和性别匹配的对照组亚组（n = 13）和 PDAC 亚组（n = 13）进行比较。在组织病理学证实的 PDAC 患者中，在肿瘤性胰腺组织（PDAC-T）和非肿瘤性胰腺组织（PDAC-NT）中分别进行测量。通过接收者操作特征曲线分析评估胰腺 THE 的诊断性能。
THE 高度可重复（组内相关系数，0.99），观察者间的一致性非常好（组内相关系数，0.97）。PDAC-T 的剪切波速度（SWS）（米/秒的平均值[95%置信区间]，1.88 ± 0.07 [1.84-1.92]）高于对照组（1.63 ± 0.04 [1.60-1.66]，P < 0.001）和 PDAC-NT（1.59 ± 0.03 [1.57-1.61]，P < 0.001）。THE 对分离 PDAC-T 的诊断性能具有探索性（接受者操作特征曲线下面积，1.0）。肿瘤性胰腺导管腺癌与对照组和 PDAC-NT 分别用 1.73 m/s 和 1.70 m/s 的截断值区分。
胰腺超声 THE 具有高度的可重复性，并基于 SWS 提供出色的成像对比度，可在不与非肿瘤性胰腺组织重叠的情况下检测 PDAC。
