Comparison of systematic sextant and lesion directed biopsies in prostate cancer detection

This study was designed to determine the value of performing separate lesion directed biopsies in addition to systematic random sextant biopsies for the detection, grading, and assessment of bilaterality of prostate cancer. A prospective study of 82 consecutive patients who had peripheral zone hypoechoic regions visualized on transrectal ultrasound was performed. All patients had either an abnormal prostate-specific antigen or an abnormal digital rectal examination and underwent random systematic and lesion directed biopsies. Cancer detection, laterality, and histologic grade of lesion directed biopsies were compared with those from systematic random biopsies. Prostate cancer was detected in 35 (40%) of 82 patients who had a hypoechoic lesion visualized. Three (9%) cancers would have been missed if only systematic biopsies had been performed, while nine (26%) cancers would have been missed if only lesion directed biopsies had been performed. In all but one patient, the Gleason score of the lesion directed biopsy was equal to or within one grade of the highest Gleason score determined from systematic biopsy. Systematic random biopsies detected cancer on the opposite side of a positive lesion directed biopsy in 48% of patients. In no case did a lesion directed biopsy add to the detection of bilateral disease. In conclusion, lesion directed biopsies increase the detection of prostate cancer when performed in addition to systematic random sextant biopsies. However, lesion directed biopsies alone would result in a substantial miss rate of prostate cancer. They do not add to the determination of bilateral disease, nor do they add to the pathologic grading of the detected cancer.