Table 3.
Summary of risk-stratification parameters in hairy cell leukemia that predict a poor prognosis and resistance to purine analogs
| Parameters | Measurement |
|---|---|
| Clinical | |
| Splenomegaly | >3 cm below the costal margin |
| Laboratory | |
| Leukocytosis | >1 × 109cells/L |
| Hairy cells in peripheral blood | >5 g/L |
| Beta-2 microglobulin level | >2× the upper limit of normal (High) |
| CD38 by immunophenotype | Present |
| Molecular features | |
| BRAFV600E | Absent |
| IGHV mutational status | Unmutated |
| IGHV4-34 rearrangement | Present |
| Telomere length | Short |
cHCL, Classical hairy cell leukemia; vHCL, hairy cell leukemia variant; CD, cluster of differentiation; IGHV, immunoglobulin heavy chain variable