Histologic grading is an important predictor of prostatic disease stage and prognosis. We aimed to assess the degree of concordance between pathologic characteristics of the specimens obtained from biopsy and radical prostatectomy materials.

Gleason scores and modified Gleason scores calculated for 25 cases of prostatic adenocarcinoma from both needle biopsy and radical prostatectomy specimens were analyzed.

Mean Gleason scores for biopsy and radical specimens were 6.4 (SD:±0.7) and 6.64 (SD:±1.3); and corresponding modified Gleason scores were 7.32 (SD:±1.43) and 7.32 (SD:±0.98), respectively. The Gleason scores of biopsy and radical prostatectomy specimens were identical in 48% (12/25) of the cases, while 32% (8/25) of the biopsy specimens were over-and 20% (5/25) of them were undergraded. While assessing modified Gleason scores, the exact degree of concordance of biopsy specimens with radical prostatectomy materials was 56% (14/25) and of the 11 (44%) cases not correlated exactly, 6 (24%) were over- and 5 (20%) were undergraded. When the exact, over- and underestimated scores of Gleason and modified Gleason grading systems were compared statistically, no difference between two groups was seen (p>0.05). Overgrading errors were found to be more than undergrading errors for both of the scoring systems. Using either the modified Gleason or traditional Gleason scoring systems, the histologic grade of the biopsy specimens is a good predictor of the final histologic grade.