The value of three-dimensional transrectal ultrasonography in staging prostate cancer

OBJECTIVE: To use three-dimensional transrectal ultrasonography (3D-TRUS) to reconstruct the prostate, and thus determine its value in staging clinically localized prostate cancer. PATIENTS AND METHODS: In all, 180 patients with newly diagnosed clinically localized prostate cancer were assessed using 3D-TRUS for staging. TRUS findings were compared with histopathological staging after radical prostatectomy. RESULTS: Pathological staging of specimens showed extracapsular extension in 69 patients, of whom 53 had pathological capsular perforation and 16 had seminal vesicle invasion. 3D-TRUS identified 58 patients with sites of extracapsular extension with 84% sensitivity, 96% specificity, 94% positive predictive value, 91% negative predictive value and an overall accuracy of 92%. Of the 16 patients with seminal vesicle invasion 14 were identified correctly on 3D-TRUS. Overall the 3D-TRUS staging sensitivity was 84%, specificity 96%, positive predictive value 93%, negative predictive value 91% and accuracy 91%. CONCLUSIONS: 3D-TRUS seems to be an accurate technique for staging localized prostate cancer. If 3D-TRUS indicates locally advanced disease, the probability of capsular perforation or seminal vesicle invasion is very high.