Literature review on the evolutional steps in updating Gleason grading system of prostatic adenocarcinoma

الملخص

The evolution of the famous original grading system for prostatic adenocarcinoma which initially  described by  Dr. Donald Gleason in the 1960s–1970s  passed through two steps  of modifications according to  two major consensus meetings achieved by the International Society of Urologic Pathology (ISUP) in 2005 and 2014 respectively according to many researches and clinical trials to be finely incorporated into the recent World health organization (WHO) classification of prostate cancer and staging system as one of the powerful prognostic factor and treatment decision factor .This articles briefly  review  historical aspects of the original Gleason grading system  and the recent modifications , describing the major changes  over the years that finely  resulted in the contemporary  Gleason grading system, which  proposed a new “Grade Group” system  established by the 2014 ISUP meeting , and then  incorporated to  the recent ( 2016) WHO classification of tumors of the prostate.