Objective To evaluate transrectal ultrasonography (TRUS) with a 7 mHz rotating probe as a staging procedure in 33 patients with localized prostatic carcinoma.
Patients and methods The ultrasound scans were compared to histopathological whole-mount step sections of the surgical specimens. Twenty-five of the patients had tumours with pathological stage T3 (pT3) and eight had tumours with stage pT2 giving a prevalence of extracapsular growth of 0.76.
Results The overall sensitivity, specificity, positive and negative predictive values for detection of extracapsular tumour growth by TRUS of prostatic cancer were found to be 0.68, 0.63, 0.85 and 0.38, respectively. Six tumours showed solely microscopic foci of extracapsular tumour growth.
Conclusion This technique gives a high percentage of both understaging (32%) and overstaging (37%) and therefore TRUS is an unreliable tool in the staging protocol prior to radical prostatectomy.