Problems in grading of prostatic carcinoma: interobserver reproducibility of five different grading systems

Interobserver and intraobserver reproducibility in digital and routine microscopic assessment of prostate needle biopsies

“…These included very good to excellent agreement for primary Gleason grade and good agreement for GS, both alone and when grouped by clinically relevant categories. These results compare favorably with the level of interobserver agreement found in traditional Gleason grading reproducibility studies using routine microscopy only [16][17][18][19][20][21][22][23][24][25].…”

“…These include primary and secondary Gleason grades, Gleason score (GS), tumor quantitation (size, percentage of core involved, or both), and perineural invasion. Although the reproducibility of the Gleason grading system has been previously studied in the past with varying case selection and results ranging from 10% to 70% interobserver agreement (Table 1) [16][17][18][19][20][21][22][23][24][25][26][27][28], only 3 studies involving urologic pathologists have been reported (Table 2) [25][26][27]. Among these, two used routine microscopy or static digital images, and one used dynamic digital microscopy, in the form of WSI.…”

A UK‐based investigation of inter‐ and intra‐observer reproducibility of Gleason grading of prostatic biopsies

“…The results for overall intra-observer variation were also good (j ¼ 0.66) and were comparable to other studies. 37,38,40 However, analysis within Gleason score groupings emphasizes the difficulty in defining Gleason 2-4 score, as 79% of the panel's first readings recorded as such were later given a higher score. Gleason 41 reported that he agreed with his previous readings exactly for 50% and within ± 1 for 85%.…”

Gleason grading: past, present and future

“…This has been reinvestigated in several studies, with variable results. Earlier studies utilizing transurethral prostatic resection or radical prostatectomy specimens showed agreement of scores to range from 36% to 66% 19–22 . For needle biopsies, reproducibility was described as adequate to satisfactory 23 .…”

“…Earlier studies utilizing transurethral prostatic resection or radical prostatectomy specimens showed agreement of scores to range from 36% to 66%. [19][20][21][22] For needle biopsies, reproducibility was described as adequate to satisfactory. 23 Among urological pathologists a 70% exact agreement of score was shown, 24 while for general pathologists agreement was found to be barely moderate (kappa = 0.435).…”