Shear wave ultrasound elastography of the prostate: Initial results - Abstract

PURPOSE: This prospective study was to evaluate shear wave elastography (SWE) in the detection of prostate cancer (PC).

 

METHODS: Patients scheduled for a transrectal ultrasound (TRUS) biopsy of the prostate because of elevated prostate-specific antigen levels or abnormal digital rectal examination result underwent a standard TRUS and SWE. A second TRUS examination and sextant biopsy by a second physician blinded to SWE results was then performed. Pathologic result was reviewed, and sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated.

RESULTS: A total of 53 patients (318 sextants) participated in the study. Mean age was 64.2 years (range, 53-79 years). A total of 26 foci of PC were detected in 11 patients (20.7%). On the basis of the receiver operating characteristic curve, a value of 37 kPa was used as the cutoff between benign and malignant. This produced a sensitivity of 96.2% (25/26), a specificity of 96.2% (281/292), a PPV of 69.4% (25/36), and an NPV of 99.6% (281/282). Six (55%) of 11 false-positive samples were secondary to benign calcifications. The Young modulus of PC ranged from 30 to 110 kPa (mean [SD], 58.0 [20.7] kPa). At the patient level, if a cutoff of 40 kPa was used, all PCs would have been detected, and the positive biopsy rate would be 11 (50%) of 22 compared to 11 (20.8%) of 53 without SWE--a 140% increase in the positive biopsy rate.

CONCLUSIONS: Shear wave elastography has a high sensitivity, specificity, PPV, and NPV for the detection of PC. With a high PPV, patients with elevated prostate-specific antigen levels or abnormal results in the digital rectal examination and negative SWE may not require biopsy. This could significantly reduce the negative biopsy rate in PC detection.

Written by: 
Barr RG, Memo R, Schaub CR. Are you the author? 
Northeast Ohio Medical University, Rootstown, OH 44512, USA.

Reference: Ultrasound Q. 2012 Mar;28(1):13-20. 
doi: 10.1097/RUQ.0b013e318249f594

PubMed Abstract 
PMID: 22357224