🔬 What the Gleason score measures
The prostate cancer tissue (from a biopsy) is examined under a microscope. The pathologist looks at how abnormal the cancer cells appear compared to normal prostate cells.
Well-differentiated (Gleason 3): Cells look somewhat normal — slower-growing.
Poorly differentiated (Gleason 4–5): Cells look very abnormal — faster-growing, more aggressive.
⚖️ How the score is calculated
Two main patterns are identified in the biopsy:
The most common pattern (primary grade)
The second most common pattern (secondary grade)
Then the two numbers are added together.
| Example | Meaning | Behavior |
|---|---|---|
| 3 + 3 = 6 | Cells look mostly normal | Low-grade, slower-growing |
| 3 + 4 = 7 | Mostly grade 3 with some more aggressive cells | Intermediate |
| 4 + 3 = 7 | Mostly grade 4 (more aggressive) | Intermediate but higher risk |
| 4 + 4 = 8 or higher | Very abnormal cells | High-grade, aggressive |
| 5 + 5 = 10 | Highly abnormal, very aggressive | High-grade |
📊 Gleason Grade Groups (simplified system)
To make it easier, doctors now often use Grade Groups (1–5):
| Grade Group | Gleason Score | Risk Level |
|---|---|---|
| 1 | 6 (3+3) | Low |
| 2 | 7 (3+4) | Favorable Intermediate |
| 3 | 7 (4+3) | Unfavorable Intermediate |
| 4 | 8 (4+4, 3+5, or 5+3) | High |
| 5 | 9–10 (4+5, 5+4, or 5+5) | Very High |
💡 Why it matters
The Gleason score helps determine:
How likely the cancer is to grow and spread
Which treatments are most appropriate
(for example, active surveillance for 3+3, but radiation + hormone therapy for 4+4 or higher)
Would you like to tell me the Gleason score or Grade Group from the pathology report (if you have it)?
I can explain exactly what it means and what treatment options are usually recommended for that score.