Implications of Observer Variation in Gleason Scoring of Prostate Cancer on Clinical Management: A Collaborative...

Prostate cancer is the most frequently diagnosed cancer in men. Histological tumour grade is a strong predictor of outcome and helps determine what treatment options are offered. There are numerous studies on Inter-observer agreement/variability on prostate cancer grading. In this study, we were looking to establish if disconcordance between pathologists when grading prostate cancer, could affect treatment options offered to men.

In Greater Manchester West Cancer Sector, all prostate cancer biopsies undergo a central review by three pathologists with a special interest in urological pathology prior to referral for treatment at specialist centres. 96 prostate biopsies (from 48 patients) from a District General Hospital were reviewed during a 6-month period (March 2014-September 2014). The original Gleason Score assigned was compared with the uropathologists consensus diagnosis established at the central review meeting. Any changes in patient risk and treatment plans were subsequently reviewed.

Of the 96 biopsies discussed at central review meeting, 24 (25%) biopsies from 19 patients underwent a change in Gleason grade and a subsequent change in risk for 13 (68%). Of the 19 patients, management plans could be affected for 9 patients (47%) and treatment options could potentially be affected for 5 (26%).

This study shows that where disconcordance between pathologists is present, there is the potential to affect patient management. A central review process can help to minimize the effect over or undergrading can have on the patient and should be considered a necessary step in the management of prostate cancer.