Digestive Endoscopy Unit, Division of Gastroenterology, Humanitas Clinical and Research Center, Milan, Italy.
Digestive Endoscopy Unit, Division of Gastroenterology, Humanitas Clinical and Research Center, Milan, Italy; Department of Biomedical Sciences, Humanitas University, Milan, Italy.
Gastrointest Endosc. 2018 Jun;87(6):1464-1473. doi: 10.1016/j.gie.2017.12.031. Epub 2018 Jan 9.
EUS elastography is useful in characterizing solid pancreatic lesions (SPLs), and fractal analysis-based technology has been used to evaluate geometric complexity in oncology. The aim of this study was to evaluate EUS elastography (strain ratio) and fractal analysis for the characterization of SPLs.
Consecutive patients with SPLs were prospectively enrolled between December 2015 and February 2017. Elastographic evaluation included parenchymal strain ratio (pSR) and wall strain ratio (wSR) and was performed with a new compact US processor. Elastographic images were analyzed using a computer program to determine the 3-dimensional histogram fractal dimension. A composite cytology/histology/clinical reference standard was used to assess sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating curve.
Overall, 102 SPLs from 100 patients were studied. At final diagnosis, 69 (68%) were malignant and 33 benign. At elastography, both pSR and wSR appeared to be significantly higher in malignant as compared with benign SPLs (pSR, 24.5 vs 6.4 [P < .001]; wSR, 56.6 vs 15.3 [P < .001]). When the best cut-off levels of pSR and wSR at 9.10 and 16.2, respectively, were used, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating curve were 88.4%, 78.8%, 89.7%, 76.9%, and 86.7% and 91.3%, 69.7%, 86.5%, 80%, and 85.7%, respectively. Fractal analysis showed a significant statistical difference (P = .0087) between the mean surface fractal dimension of malignant lesions (D = 2.66 ± .01) versus neuroendocrine tumor (D = 2.73 ± .03) and a statistical difference for all 3 channels red, green, and blue (P < .0001).
EUS elastography with pSR and fractal-based analysis are useful in characterizing SPLs. (Clinical trial registration number: NCT02855151.).
EUS 弹性成像是用于描述实性胰腺病变（SPL）的有用工具，基于分形分析的技术已用于评估肿瘤的几何复杂性。本研究的目的是评估 EUS 弹性成像（应变比）和分形分析在描述 SPL 方面的应用。
连续纳入 2015 年 12 月至 2017 年 2 月期间的 SPL 患者进行前瞻性研究。弹性评估包括实质应变比（pSR）和壁应变比（wSR），使用新型紧凑式 US 处理器进行。使用计算机程序分析弹性图像以确定 3 维直方图分形维数。使用细胞学/组织学/临床综合参考标准来评估敏感性、特异性、阳性预测值、阴性预测值和受试者工作特征曲线下面积。
共有 100 例患者的 102 个 SPL 进行了研究。最终诊断为恶性病变 69 例（68%），良性病变 33 例。在弹性成像方面，恶性 SPL 的 pSR 和 wSR 均显著高于良性 SPL（pSR：24.5 比 6.4[P<0.001]；wSR：56.6 比 15.3[P<0.001]）。当分别使用最佳 pSR 和 wSR 截断值 9.10 和 16.2 时，敏感性、特异性、阳性预测值、阴性预测值和受试者工作特征曲线下面积分别为 88.4%、78.8%、89.7%、76.9%和 86.7%和 91.3%、69.7%、86.5%、80%和 85.7%。分形分析显示恶性病变的平均表面分形维数（D=2.66±0.01）与神经内分泌肿瘤（D=2.73±0.03）之间存在显著统计学差异（P=0.0087），并且所有 3 个通道（红色、绿色和蓝色）之间存在统计学差异（P<0.0001）。
EUS 弹性成像与基于分形分析的 pSR 有助于描述 SPL。（临床试验注册号：NCT02855151）。
