Doctors now use Grade Groups to classify prostate cells in a lesion. (The groups replace Gleason scores like 3+3, 3+4, etc.) They’re based largely on how much Pattern 4 is present:
- Grade Group 1: No Pattern 4
- Grade Group 2: Less than half are Pattern 4
- Grade Group 3: More than half are Pattern 4
- Grade Group 4: All cells are Pattern 4
- Grade Group 5: Any cells are Pattern 5
To many experts, Group 1 can be followed with active surveillance, Groups 3 to 5 require treatment, and Group 2 is a gray zone.