Academic Section of Urology, Division of Cancer, Medical Research Institute, Ninewells Hospital, University of Dundee, Dundee DD1 4HN, UK.
Surg Endosc. 2013 Sep;27(9):3280-7. doi: 10.1007/s00464-013-2906-7. Epub 2013 Mar 23.
Shear wave imaging (SWI) is a new ultrasound technique whose application facilitates quantitative tissue elasticity assessment during transrectal ultrasound biopsies of the prostate gland. The aim of this study was to determine whether SWI quantitative data can differentiate between benign and malignant areas within prostate glands in men suspected of prostate cancer (PCa).
We conducted a protocol-based, prospective, prebiopsy quantitative SWI of prostate glands in 50 unscreened men suspected of prostate cancer between July 2011 and May 2012. The ultrasound image of whole prostate gland was arbitrarily divided into 12 zones for sampling biopsies, as is carried out in routine clinical practice. Each region was imaged by grey scale and SWI imaging techniques. Each region was further biopsied irrespective of findings of grey scale or SWI on ultrasound. Additional biopsies were taken if SWI abnormal area was felt to be outside of these 12 zones. Quantitative assessment of SWI abnormal areas was obtained in kilopascals (kPa) from abnormal regions shown by SWI and compared with histopathology. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios were calculated for SWI (histopathology was a reference standard).
Fifty patients, with a mean age of 69 ± 6.2 years, were recruited into the study. Thirty-three (66%) patients were diagnosed with PCa, while an additional 4 (8%) had atypia in at least one of the 12 prostate biopsies. Thirteen (26%) patients had a benign biopsy. Data analysed per core for SWI findings showed that for patients with PSA <20 μg/L, the sensitivity and specificity of SWI for PCa detection were 0.9 and 0.88, respectively, while in patients with PSA >20 μg/L, the sensitivity and specificity were 0.93 and 0.93, respectively. In addition, PCa had significantly higher stiffness values compared to benign tissues (p <0.05), with a trend toward stiffness differences in different Gleason grades.
SWI provides quantitative assessment of the prostatic tissues and, in our preliminary observation, provides better diagnostic accuracy than grey-scale ultrasound imaging.
剪切波成像（SWI）是一种新的超声技术，其应用可在经直肠前列腺超声活检过程中辅助定量组织弹性评估。本研究旨在确定 SWI 定量数据是否可区分疑似前列腺癌（PCa）男性的前列腺内良性和恶性区域。
我们在 2011 年 7 月至 2012 年 5 月间对 50 名未经筛选疑似前列腺癌的男性进行了基于方案的前瞻性术前 SWI 定量检查。整个前列腺的超声图像被任意划分为 12 个区域进行采样活检，这是常规临床实践中进行的。每个区域都通过灰阶和 SWI 成像技术进行成像。每个区域都进行了活检，无论灰阶或超声 SWI 结果如何。如果感觉 SWI 异常区域超出这 12 个区域，则进行额外的活检。从 SWI 显示的异常区域获得 SWI 异常区域的千帕斯卡（kPa）定量评估，并与组织病理学进行比较。计算 SWI 的灵敏度、特异性、阳性和阴性预测值以及似然比（组织病理学是参考标准）。
50 名患者，平均年龄 69±6.2 岁，入组本研究。33 名（66%）患者被诊断为 PCa，而另外 4 名（8%）在 12 个前列腺活检中有一个以上存在非典型性。13 名（26%）患者的活检结果为良性。对 SWI 结果进行每针分析显示，对于 PSA<20μg/L 的患者，SWI 对 PCa 检测的灵敏度和特异性分别为 0.9 和 0.88，而对于 PSA>20μg/L 的患者，灵敏度和特异性分别为 0.93 和 0.93。此外，PCa 的硬度值明显高于良性组织（p<0.05），不同 Gleason 分级的硬度值也有差异趋势。
SWI 提供了前列腺组织的定量评估，并且在我们的初步观察中，比灰阶超声成像提供了更好的诊断准确性。
