EAU 2017: 4th ESO Prostate Cancer Observatory: The Pathologist’s Perspective

London, England (UroToday.com) Dr. Van der Kwast provided a very informative and spirited presentation today regarding the pathologist’s perspective on prostate cancer at the EAU 2017’s 4th ESO Prostate Cancer Observatory.

One of the more significant achievements of 2016 included incorporation of the International Society of Urological Pathology (ISUP) 2014 Gleason group grading system into the EAU-ESTRO-SIOG guidelines on prostate cancer.1 Dr. Van der Kwast also highlighted essential changes from the ISUP 2014 meeting, including (i) introducing five (1-5) Gleason grade groups, (ii) inclusion of all cribriform patters as Gleason grade 4 disease, (iii) reporting the percentage of Gleason grade 4 in Gleason score 7 biopsies, and (iv) separate reporting of intraductal carcinoma, although not including this entity in the grading system. As Dr. Van der Kwast points out, the reason for quantitative grading of Gleason grade 4 in Gleason score 7 biopsies is that some of these patterns may be indolent and there may be some difficulty with ill-formed and fused pattern 4 prostate cancers. Furthermore, men with a lower percentage of pattern 4 disease (<20%) may be candidates for active surveillance protocols.

One of the main adoptions Dr. Van der Kwast hopes to see in the next 12 months is for pathologists to report the global Gleason score, which he describes as taking into account the Gleason score of all carcinoma positive biopsy specimens, as well as their extent and percentage of high grade. For example, a man with 10% Gleason 4+4 on biopsy 1, 40% Gleason 3+3 on biopsy 2, and 10% Gleason 3+3 on biopsy 5 would have a global Gleason score of 3+4=7.

Finally, Dr. Van der Kwast sees the next 12 months as the “Year of Gleason pattern 4”, highlighting the “mixed bag” that suggests “all Gleason pattern 4 are equal, but some are more equal than others”. Ultimately, we may see Gleason pattern 4 sub-pathologies emerge to further delineate lower and higher risk Gleason 4 disease.

1. Mottet N, Bellmunt J, Bolla M, et al. EAU-ESTRO-SIOG Guidelines on Prostate Cancer. Part 1: Screening, Diagnosis, and Local Treatment with Curative Intent. Eur Urol 2017;71(4):618-629.

Presented by: Theodorus Van der Kwast, Princess Margaret Cancer Centre, University Health Network, Toronto, Canada

Written by: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto
Twitter: @zklaassen_md

at the #EAU17 -March 24-28, 2017- London, England