C91.3 is a "category code," which means it's non-billable. Billable codes require more specificity. Use the list below to navigate to codes that are more specific:
10
C91.30
Prolymphocytic leukemia of B-cell type not having achieved remission
Billable
10
C91.31
Prolymphocytic leukemia of B-cell type, in remission
Billable
10
C91.32
Prolymphocytic leukemia of B-cell type, in relapse
Billable