The usefulness of power Doppler ultrasonography for diagnosing prostate cancer: histological correlation of each biopsy site

Objective To correlate the findings of power Doppler ultrasonography (PDUS) of the prostate with those of site-specific transrectal ultrasonography (T RUS)guided biopsy. Patients and methods The study comprised 28 patients referred to our instit ution for TRUS-guided prostate biopsy because of an elevated PSA level and/ or abnormal digital rectal examination. PDUS findings were graded 0, 1 or 2 ; grades 0-1 were considered as negative and grade 2 as positive. The blood volume of each biopsy site was also determined using the mean number (MN) value that represents the average vascularity in a 5-mm square sample. PDUS values were correlated with the histological findings of 147 biopsies with 19 focal lesions. Results Grade 2 was assigned to 19 sites, grade 1 to 52 sites, and grade 0 to 76 sites. Fourteen of the 19 PDUS findings of grade 2 sites revealed car cinoma and five were grade 1. Ten of 35 TRUS-positive sites were carcinomas , three benign prostatic hyperplasia (BPH) and 22 normal. The MN value for prostatic carcinoma was 4.33, for BPH 11.7 and for normal tissue 4.7. The o verall sensitivity of PDUS was 74%, the specificity 96% and the positive pr edictive value 74%. Conclusions Because TRUS alone cannot detect all cancers. PDUS should be us ed routinely in all patients undergoing TRUS-guided biopsy, to improve the diagnostic yield of prostate cancer.