Journal belge de radiologie vol:78 issue:6 pages:356-8
Hypoechoic lesions in the peripheral zone of the prostate gland are one of the commonest abnormalities at transrectal ultrasonography (TRUS). 90% of all carcinomas originating in the peripheral zone present as a hypoechoic lesion. Hypoechogenicity though is not specific, as many benign lesions are also hypoechoic. In this retrospective study, based on TRUS alone 57% of the hypoechoic lesions showed carcinoma in the biopsy core (43% of the biopsy cores were benign). The number of positive biopsies increased up to 75% when the hypoechoic lesion was palpable at digital rectal examination. 5.2% of the hypoechoic cancers would have been missed when non-palpable lesions would not have had a biopsy. When the hypoechoic lesion was associated with increased serum concentration of prostate specific antigen (PSA > 4 ng/ml) 74% of the biopsies were positive. 20% to 25% of all hypoechoic cancers would not have had a biopsy. The positive predictive value was 85% when the hypoechoic lesion was palpable at digital rectal examination and the PSA-concentration was > 4 ng/ml (and 90% when volume-adjusted PSA-parameter would have been applied).