The impact of real-time tissue elasticity imaging (elastography) on the detection of prostate cancer: Clinicopathological analysis

Background. We evaluated the accuracy and feasibility of real-time elastography for detecting prostate cancer, using prostatectomy specimens. Methods. This study was based on clinicopathological findings in 51 patients with prostate cancer who were referred for elastography at the time of prostate biopsy. We compared transverse pathology sections with elastographic moving images (EMIs) to determine the detection rate of cancer, the relationship between tumor location and the elastographic findings, and the relationship between the Gleason score and the elastographic findings. Results. In 15 patients (29%), all EMIs were in complete agreement with tumor location (category I), in 28 patients (55%), the EMIs agreed with tumor location, but showed some disagreement (category II), and in 8 patients (16%) there was disagreement of the elastographic findings with tumor location or the tumors were undetectable by elastography (category III). However, in category III, all tumors were detected as low-echoic by B-mode ultrasonography. We divided the prostate into three different regions (anterior, middle, and posterior), and found that 30/32 (94%) anterior tumors, 13/17 (76%) middle tumors, and 16/28 (57%) posterior tumors were detected by elastography. The proportions of cancers detected by elastography (categories I+II/total) was 100% in the patients with a Gleason score of 6, 85% in those with a score of 7 or 8, and 63% in those with a score of 9 or 10. Conclusion. Real-time elastography in conjunction with B-mode ultrasonography significantly improves the detection of prostate cancer. One of the characteristic findings of elastography is its excellent detection of anterior tumors. The low detection rate of high-grade tumors in this analysis was likely due to the predominance of high-grade tumors in a peripheral location compared to the anterior location of the low-grade tumors.