Boehm Katharina, Salomon Georg, Beyer Burkhard, Schiffmann Jonas, Simonis Kathrin, Graefen Markus, Budaeus Lars
Martini Clinic, Prostate Cancer Center at University Hospital Hamburg-Eppendorf, Hamburg, Germany.
Martini Clinic, Prostate Cancer Center at University Hospital Hamburg-Eppendorf, Hamburg, Germany.
J Urol. 2015 Mar;193(3):794-800. doi: 10.1016/j.juro.2014.09.100. Epub 2014 Sep 28.
Shear wave elastography allows the detection of cancer by using focused ultrasound pulses for locally deforming tissue. The differences in tissue elasticity and stiffness have been used increasingly in breast cancer imaging and help detect potential tumor lesions in the prostate. In this study we localized prostate cancer lesions using shear wave elastography before radical prostatectomy and assessed the examiner independent elasticity threshold for cancer foci detection.
Shear wave elastography scanning of the whole prostate was performed before radical prostatectomy in 60 consecutive patients with high, intermediate and low risk disease. Localization of suspected lesions and density threshold (kPa) were recorded in up to 12 areas and resulted in 703 different fields. Shear wave elastography findings were correlated with final pathology. Initially 381 areas were used to establish shear wave elastography cutoffs (development cohort 32 patients). Subsequently these cutoffs were validated in 322 areas (validation cohort 28 patients).
Using shear wave elastography significant differences were recorded for the elasticity of benign tissue vs prostate cancer nodules at 42 kPa (range 29 to 71.3) vs 88 kPa (range 54 to 132) (all p <0.001). Median cancer lesion diameter was 26 mm (range 18 to 41). Applying the most informative cutoff of 50 kPa to the validation cohort resulted in 80.9% and 69.1% sensitivity and specificity, respectively, and 74.2% accuracy for detecting cancer nodules based on final pathological finding. The corresponding positive and negative predictive values were 67.1% and 82.2%, respectively.
Shear wave elastography allows the identification of cancer foci based on shear wave elastography differences. Moreover, reliable cutoffs for this approach can be established, allowing examiner independent localization of prostate cancer foci.
剪切波弹性成像通过使用聚焦超声脉冲使组织局部变形来检测癌症。组织弹性和硬度的差异在乳腺癌成像中越来越多地被应用，并有助于检测前列腺中的潜在肿瘤病变。在本研究中，我们在根治性前列腺切除术之前使用剪切波弹性成像对前列腺癌病变进行定位，并评估用于检测癌灶的独立于检查者的弹性阈值。
对60例连续的高、中、低风险疾病患者在根治性前列腺切除术之前进行整个前列腺的剪切波弹性成像扫描。在多达12个区域记录疑似病变的定位和密度阈值（kPa），共得到703个不同区域。剪切波弹性成像结果与最终病理结果相关。最初，381个区域用于确定剪切波弹性成像的临界值（开发队列32例患者）。随后，在322个区域对这些临界值进行验证（验证队列28例患者）。
使用剪切波弹性成像记录到，良性组织与前列腺癌结节的弹性存在显著差异，分别为42 kPa（范围29至71.3）和88 kPa（范围54至132）（所有p<0.001）。癌灶的中位直径为26 mm（范围18至41）。将最具信息性的临界值50 kPa应用于验证队列，基于最终病理结果检测癌结节的敏感性和特异性分别为80.9%和69.1%，准确性为74.2%。相应的阳性和阴性预测值分别为67.1%和82.2%。
剪切波弹性成像能够基于剪切波弹性成像差异识别癌灶。此外，可以建立该方法的可靠临界值，实现独立于检查者的前列腺癌灶定位。
