The Gleason Score & ISUP Grading (how aggressive the cancer is)
Gleason Score
This is given after a pathologist has examined under a microscope cancerous tissue obtained from the needle biopsy. The cells identified are given a grade number from 1 to 5, depending on the abnormality of the cells, 1 being the lowest, 5 the highest. The grades of the two most common patterns are added together to give a score from 2 to 10. The higher the score, the more aggressive and fast-growing the cancer. Scores totalling 5 or less are insignificant and are not reported.
- A Gleason score of 6 (cells are well differentiated) is ‘favourable’
- A Gleason score of 7 (cells are moderately differentiated) is ‘average’
- A Gleason Score of 8–10 (cells are poorly differentiated) is ‘adverse’
The consultant will give you a total score out of 10, which should be split down as two numbers out of 5: for example, 4+3. The first number is the predominant grade, so a score of 4+3=7, for example, is likely to prove slightly more aggressive than a score of 3+4=7.
Gleason patterns
(Grade 5 is the most aggressive)
ISUP Grading
In 2014, the International Society of Urological Pathology released supplementary guidance and a revised prostate cancer grading system called the ISUP Grade Groups. The ISUP Grade Group system is simpler, with just five grades, 1 to 5.
Your consultant may report your score either as a Gleason Score or an ISUP Grade Group, or you may receive both scores.
ISUP Grading
Risk Group |
ISUP Grade Group |
Gleason Score |
Low |
Grade Group 1 |
Gleason <6 |
Intermediate Favourable |
Grade Group 2 |
Gleason 7 (3+4) |
Intermediate Unfavourable |
Grade Group 3 |
Gleason 7 (4+3) |
High |
Grade Group 4 |
Gleason 8. |
High |
Grade Group 5 |
Gleason 9–10 |