Clinical significance of small (less than 0.2 cm3) hypoechoic lesions in men with normal digital rectal examinations and prostate-specific antigen levels less than 10 ng/ mL

Abstract

Objectives. Most men diagnosed with prostate cancer in 1998 presented with a normal digital rectal examination (DRE) and minimal elevations in serum prostate-specific antigen (PSA) (less than 10 ng/mL). Considerable attention is often given toward identifying small hypoechoic (less than 0.2 cm 3) lesions at the time of transrectal ultrasound-guided prostate biopsy. We sought to determine the significance of these lesions and whether an additional biopsy of this area is clinically useful. Methods. A prospective data base containing detailed information on 614 biopsies performed by a single urologist was examined. All patients with a hypoechoic lesion underwent sextant prostate biopsy plus a separately labeled core directed through the hypoechoic area. Eighty-one patients who fit the following criteria were assessed: PSA less than 10 ng/mL, normal DRE, and hypoechoic lesion volume less than 0.2 cm 3. Results. The mean age of this group was 63.5 years, and the mean PSA was 7.1 ng/mL. Of the 81 patients with small hypoechoic lesions, 20 (24.7%) were positive for cancer in at least one prostatic core. Of the 81 hypoechoic area biopsies (HABs), 14 (17.3%) were positive for cancer; 1 (1.2%) demonstrated high-grade prostatic intraepithelial neoplasia, and 66 (81.5%) were negative. In 11 of the patients (78.6%) with positive HABs, at least one additional core was positive for cancer. In 3 of the patients (21.4%) with positive HABs, no additional cores were positive for cancer ( P < 0.05) . Conclusions. A significant proportion of small hypoechoic lesions in patients with early T1c prostate cancer are positive for malignancy. Although the overall yield of separate hypoechoic area biopsy is low (3.7%), approximately 15% of cancers would be missed if directed HABs were not performed ( P < 0.05). Identification and biopsy of small hypoechoic lesions are indicated in this group of patients.