Department of radiodiagnosis and intervention, faculty of medicine, Alexandria university, Alexandria, Egypt.
AMEOS Hospital Halberstadt, Halberstadt, Germany.
Br J Radiol. 2020 Jun;93(1110):20200035. doi: 10.1259/bjr.20200035. Epub 2020 Mar 23.
Ultrasound elastography is increasingly used in the diagnosis of prostate cancer, however results are heterogeneous. We correlate in a large sample-size prospective study the accuracy of elastography, aiming to settle an accurate cut-off point for diagnosis and possibility of use as a screening tool.
Prospective study that included 120 patients with mean age 59.5 ± 9.8 years, showing enlarged prostate by clinical examination with prostate-specific antigen >4 ng ml.The study was done using high frequency high resolution endorectal probe with real time tissue elastography.Grayscale ultrasound examination was done first with Doppler followed by elastography color-coded map and strain ratio measurement. Then, transrectal ultrasound-guided core biopsy was done from suspicious areas detected by elastography (totally or partly stiff by color-coded map or with relative increased strain ratio), besides standard six-quadrant core biopsy samples.
There was statistically significant difference ( < 0.001) regarding strain ratio in benign and malignant lesions. Strain ratio showed significant proportionate correlation with prostate-specific antigen level and Gleason pathological score, while no significant correlation noted with the age or the prostatic volume. A strain ratio with a cut-off value of 1.9 showed a sensitivity of 100%, specificity 93.8%, positive predictive value of 79.3%, negative predictive value 100 and 95% accuracy in differentiating between malignant and benign lesions.
Strain ratio improves the detection of prostatic cancer with high sensitivity (100%) and high negative predictive value (100%).
Different prostatic lesions are mostly similar in grayscale ultrasound.Imaging plays an important role in differentiation of prostatic nodules.Ultrasound elastography may play an important role in distinguishing benign from malignant nodules.
超声弹性成像在前列腺癌的诊断中应用越来越广泛，但结果存在异质性。我们在一项大样本前瞻性研究中对弹性成像的准确性进行了相关性分析，旨在确定一个准确的诊断临界点和作为筛查工具的可能性。
前瞻性研究纳入了 120 名平均年龄为 59.5±9.8 岁的患者，这些患者通过临床检查发现前列腺体积增大，前列腺特异性抗原（PSA）>4ng/ml。研究使用高频高分辨率直肠内探头进行，实时组织弹性成像。首先进行灰阶超声检查，然后进行多普勒检查，接着进行弹性成像彩色编码图和应变比测量。然后，根据弹性成像（彩色编码图上完全或部分僵硬或相对应变比增加的可疑区域）进行经直肠超声引导的核心活检，除了标准的六区核心活检样本。
良性和恶性病变之间的应变比存在统计学显著差异（<0.001）。应变比与 PSA 水平和 Gleason 病理评分呈显著比例相关，而与年龄或前列腺体积无显著相关性。应变比的截断值为 1.9 时，在区分良恶性病变方面具有 100%的敏感性、93.8%的特异性、79.3%的阳性预测值、100%的阴性预测值和 95%的准确性。
应变比以 100%的高敏感性和 100%的高阴性预测值提高了前列腺癌的检出率。
不同的前列腺病变在灰阶超声上大多相似。影像学在前列腺结节的鉴别中起着重要作用。超声弹性成像在区分良性和恶性结节方面可能发挥重要作用。
