The impact of real-time elastography guiding a systematic prostate biopsy to improve cancer detection rate: a prospective study of 353 patients.

ABSTRACT

PURPOSE: We evaluated whether real-time elastography guided biopsy improves prostate cancer detection compared to conventional systematic gray scale ultrasound guidance. MATERIALS AND METHODS: A total of 353 consecutive patients suspicious for prostate cancer were prospectively randomized for real-time elastography (178) or gray scale ultrasound (175). Each patient enrolled in the study underwent a 10-core prostate biopsy. Six lateral prostate sectors (base, mid, apex) were scanned for cancer suspicious areas, defined as stiffer blue lesions using real-time elastography and hypoechoic lesions using gray scale ultrasound. Suspicious areas were sampled by a single targeted biopsy and considered representative of a defined prostate sector. If real-time elastography or gray scale ultrasound did not visualize a suspicious area in a sector, the biopsy core was taken systematically. Imaging findings were correlated with histopathological reports. Real-time elastography and gray scale ultrasound cases were compared in terms of cancer detection rate and imaging guidance accuracy. RESULTS: Characteristics of patients undergoing real-time elastography and gray scale ultrasound, including age, prostate specific antigen, prostate volume and digital rectal examination, were not significantly different (p>0.05). Prostate cancer was detected in 160 of 353 patients (45.3%). The prostate cancer detection rate was significantly higher in patients who underwent biopsy with the real-time elastography guided approach compared to the gray scale ultrasound guided biopsy at 51.1% (91 of 178) vs 39.4% (69 of 175) (p=0.027). Overall sensitivity and specificity to detect prostate cancer was 60.8% and 68.4% for real-time elastography vs 15% and 92.3% for gray scale ultrasound, respectively. CONCLUSIONS: Sensitivity to visualize and detect prostate cancer improved using real-time elastography in addition to gray scale ultrasound during prostate biopsy. Overall sensitivity did not reach levels to omit a systematic biopsy approach.