Gleason score

«The Gleason is a grade assigned to prostate cancer specimens that reflects the degree of aggressiveness based on the tumor's resemblance to normal glandular tissue. A primary (or predominant) pattern is recorded followed by a secondary or lesser pattern. The Gleason score is the sum of the primary and secondary pattern values and can be between 2 and 10» [1].

The original Gleason grading system diagram:

Source: Gordetsky J, Epstein J. Grading of prostatic adenocarcinoma: current state and prognostic implications. Diagn Pathol. 2016 Mar 9;11:25. Available at: https://doi.org/10.1186/s13000-016-0478-2. The link to the Creative Commons Attribution 4.0 International License is http://creativecommons.org/licenses/by/4.0/.

«Grade 1: small, well-formed glands, closely packed;

Grade 2: well-formed glands, but more tissue between them;

Grade 3: darker cells, some of which have left the gland and are invading the surrounding tissue;

Grade 4: few recognizable glands with many cells invading the surrounding tissue;

Grade 5: no recognizable glands; sheets of cells throughout the surrounding tissue» [1].

The current guidelines for the Gleason grading system and recent changes from the 2014 International Society of Urological Pathology (ISUP) consensus conference on Gleason grading of prostatic carcinoma include five distinct grade groups based on the modified Gleason score groups. Grade Group 1 = Gleason score ≤6, Grade Group 2 = Gleason score 3 + 4 = 7, Grade Group 3 = Gleason score 4 + 3 = 7, Grade Group 4 = Gleason score 8, Grade Group 5 = Gleason scores 9 and 10. This new ISUP grading system is simpler and more accurately reflects prostate cancer biology, and it is recommended by the World Health Organization (WHO) to be used in conjunction with Gleason grading [10].

Bibliographic references:

[1] Shah A. 53 - Low-Risk Prostate Cancer. In: Hristov B, Lin S, Christodouleas J. Radiation Oncology. 2nd ed. Philadelphia, USA: Wolters Klumer Health; 2015:364.

[2] Gordetsky J, Epstein J. Grading of prostatic adenocarcinoma: current state and prognostic implications. Diagn Pathol. 2016 Mar 9;11:25. Available at: https://doi.org/10.1186/s13000-016-0478-2. The link to the Creative Commons Attribution 4.0 International License is http://creativecommons.org/licenses/by/4.0/.