Is preoperative transrectal ultrasonography of value in localised prostatic carcinoma? A blind comparative study between preoperative transrectal ultrasonography and the histopathological radical prostatectomy specimen.

Digital rectal examination (DRE) for staging is subjective and unreliable. Understaging has been reported in 25-72% and clinical overstaging of T3 tumors varies from 24-50%. In the present study of 15 patients, transrectal ultrasound (TRUS) staging was compared, in a blind comparative fashion, with pathological staging of the surgical specimen. Multifocal lesions were present in 8/15 patients (53%). A distinction was made between capsular involvement and 'clear' capsular penetration. TRUS was more sensitive in predicting capsular involvement than DRE (83% vs 17%), but the specificity was low (67% vs 100%). If capsular perforation was considered, the sensitivity and specificity of TRUS are 43% and 91%, respectively. Sensitivity and specificity for seminal vesicle tumor involvement by TRUS was 63% and 86%. Using TRUS the overall staging was improved by 33% compared with DRE and therefore TRUS is considered to be a valuable acquisition in localising and staging prostate cancer