The Cardiovascular
ToolsCalculators

Gleason Score for Prostate Cancer

Combines the two most prevalent histologic patterns into a prognostic score and ISUP grade group.

Gleason Score for Prostate Cancer
Primary (most prevalent) pattern
The most common architectural pattern seen.
Secondary (next most prevalent) pattern
The second most common pattern; equals the primary pattern if the tumour is uniform.
ResultGleason 1+1 = 2

ISUP Grade Group 1.

Gleason score
1 + 1 = 2
ISUP Grade Group
1

When to use

  • Grading prostate adenocarcinoma on biopsy or prostatectomy specimen to guide risk stratification and treatment selection.

Formula

Gleason score = primary (most prevalent) pattern + secondary (next most prevalent) pattern (each graded 1-5, contemporary practice essentially 3-5). ISUP Grade Group: <=6 -> GG1; 3+4 -> GG2; 4+3 -> GG3; 8 -> GG4; 9-10 -> GG5.

Pearls and pitfalls

  • Contemporary practice rarely assigns patterns 1-2; scores below 3+3=6 are uncommon in current biopsies.
  • If only one pattern is present, it is used as both primary and secondary (e.g. 3+3).

References

  1. Gleason DF. Cancer Chemother Rep. 1966;50(3):125-8.
  2. Epstein JI, Egevad L, Amin MB, et al. Am J Surg Pathol. 2016;40(2):244-52.