PURPOSE: To retrospectively compared the usefulness of the transrectal ultrasonography LEAVE A SPACE(TRUS) and systemic sextant biopsy in the diagnosis of prostate cancer. MATERIALS AND METHODS: A total of 84 patients with clinical and laboratory findings suggestive of prostate cancer underwent TRUS and systemic sextant biopsy. Nine patients with diffuse prostatic lesion had been excluded from the list. Following sonographic evaluation, additional targeted biopsy for the focal lesion was performed in 14 patients. A total of 464 biopsy specimens were obtained and retrospectively compared with the sonographic findings. RESULTS: For cancer, the sensitivity, specificity and false-positive rate of TRUS were 48%, 97% and 53%, respectively. The hypoechoic nodules seen in prostate cancer were more commonly located in the outer half of the peripheral zone of the prostate, while most BPH lesions were located in the inner half of this zone. Between prostate cancer and BPH there was a statistically significant difference in the location of hypoechoic nodules revealed by TRUS (p=0.01). CONCLUSION: The location of the hypoechoic nodules provides useful information for differentiating between BPH nodoles and malignant prostatic nodules and may reduce the false-positive rate of TRUS in the diagnosis of prostate cancer.