Discrepancies in Gleason score between needle core biopsy and radical prostatectomy specimens with correlation between clinical and pathological staging.

Abstract

Background: The studies have shown that GS given after assessment of the entire prostate gland on the radical prostatectomy specimen may differ from GS given after examination of a small sample from needle core biopsy. We conducted this study to assess discrepancies in the Gleason score between NCB and RP specimens and to find out the correlation between the clinical stage and pathological stage.

Methods: The study included 174 patients with carcinoma prostate which underwent robotic-assisted radical prostatectomy (RARP). Pre-operative Gleason score was determined on 12-core biopsy samples under trans-rectal ultrasound (TRUS) guidance. The Gleason score obtained from the radical prostatectomy specimen was compared with that of the NCB Gleason score to find out differences.

Results: The preoperative Gleason score (GS) ranges from 6 to 9 with a mean GS of 6.97 ± 1.02. The post-operative GS ranges between 6 and 10 with mean and GS of 7.5 ± 1.10. On the pre-operative assessment of biopsy specimens, 70 (43.2%) patients had a GS of 6, while 44 patients had a GS of 7 (27.1%) and 48 (29.8%) patients had a GS of more than 7. On the postoperative assessment of specimens, 31 (19.1%) patients had post-operative GS of 6, while 66 (41%) patients had GS of 7 and 74 (41.1%) patients had GS of more than 7. When pre-operative GS and post-operative GS were compared, no changes were observed in the GS of 79 patients, whereas 83 patients showed the difference in GS, with 75 patients showing up-gradation and eight patients marked as down-graded.

Conclusion: concordance between biopsy and the pathology results directly affects the prognosis of the patient. The results of our study demonstrated the rate of discordance between Gleason scores obtained from transrectal prostate biopsy and RP surgical specimens. This rate brings into question the accuracy of the chosen treatment.