Accuracy of Grading Gleason Score 7 Prostatic Adenocarcinoma on Needle Biopsy: Influence of Percent Pattern 4 and Other Histological Factors.
BACKGROUND
Recognition of Gleason pattern 4 in prostatic needle biopsies is crucial for both prognosis and therapy. Recently, it has been recommended to record percent pattern 4 when Gleason score 7 cancer is the highest grade in a case.


METHODS
Four hundred and five prostate needle core biopsies received for a second opinion at our institution from February-June, 2015 were prospectively diagnosed with prostatic adenocarcinoma Gleason score 7 as the highest score on review by a consultant urological pathologist. Percentage of core involvement by cancer, percentage of Gleason pattern 4 per core, distribution of Gleason pattern 4 (clustered, scattered), morphology of pattern 4 (cribriform, non-cribriform), and whether the cancer was continuous or discontinuous were recorded.


RESULTS
Better agreement was noted between the consultant and referring pathologists when pattern 4 was clustered as opposed to dispersed in biopsies (P = 0.009). The percentage of core involvement by cancer, morphology of pattern 4, and continuity of cancer did not affect the agreement between the consultant and referring pathologists. There was a trend (P = 0.06) for better agreement based on the percent of pattern 4.


CONCLUSIONS
When pattern 4 is scattered amongst pattern 3 as opposed to being discrete foci, there is less interobserver reproducibility in grading Gleason score 7 cancer, and in this setting pathologists should consider obtaining second opinions either internally within their group or externally. Prostate 77: 681-685, 2017. © 2017 Wiley Periodicals, Inc.
The Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Abdelrazak
A
Meliti
The Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Evita
E
Sadimin
The Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Mario
M
Diolombi
The Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Francesca
F
Khani
The Departments of Urology and Oncology, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Jonathan I
JI
Epstein
D000230:Adenocarcinoma / Q000473:pathology*; D001707:Biopsy, Needle / Q000379:methods / Q000592:standards; D006801:Humans; D008297:Male; D060787:Neoplasm Grading / Q000379:methods / Q000592:standards; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000473:pathology*
gleason grading; interobserver; percent pattern 4; prostate cancer