Correlation between the Gleason Scores of Needle Biopsies and Radical Prostatectomy Specimens.

Background: The Gleason score has been shown to offer important information withregard to prognosis and therapy for patients with adenocarcinoma of theprostate gland. In this study, Gleason scores, as determined by 18-gauge coreneedle biopsies, were compared with both Gleason scores and the pathologicalstaging of corresponding radical prostatectomy specimens.Methods: Records of 78 consecutive patients undergoing a radical retropubic prostatectomybetween 1998 and 2002 were reviewed. In total, 78 patients wereenrolled, all of whom had been diagnosed with adenocarcinoma by transrectalneedle biopsies using an 18-gauge automated spring-loaded biopsy gun.Results: Grading errors were greatest with well-differentiated tumors. The accuracywas 6 (23%) for Gleason scores of 2-4 on needle biopsy. Of the 36 evaluablepatients with Gleason scores of 5-7 on needle biopsy, 28 (78%) were gradedcorrectly. All of the Gleason scores of 8-10 on needle biopsy were gradedcorrectly. Eighteen (33%) of 54 patients with a biopsy Gleason score of < 7had their cancer upgraded to above 7. Tumors in 6 patients (60%) with both aGleason score < 7 on the needle biopsy and a Gleason score of 7 for theprostatectomy specimen were confined to the prostate.Conclusion: The potential for grading errors is greatest with well-differentiated tumorsand in patients with a Gleason score of < 7 on the needle biopsy. Predictionsusing Gleason scores are sufficiently accurate to warrant its use with all needlebiopsies, recognizing that the potential for grading errors is greatest withwell-differentiated tumors.