The International Working Group for Myelofibrosis Research and Treatment (IWG-MRT) International Prognostic Scoring System for Primary Myelofibrosis (IPSS-PMF)4
| Risk group . | No. of risk factors* . | Median survival, mo (95% CI) . |
|---|---|---|
| Low | 0 | 135 (117-181) |
| Intermediate 1 | 1 | 95 (79-114) |
| Intermediate 2 | 2 | 48 (43-59) |
| High | ≥ 3 | 27 (23-31) |
| Risk group . | No. of risk factors* . | Median survival, mo (95% CI) . |
|---|---|---|
| Low | 0 | 135 (117-181) |
| Intermediate 1 | 1 | 95 (79-114) |
| Intermediate 2 | 2 | 48 (43-59) |
| High | ≥ 3 | 27 (23-31) |
Risk factors for primary myelofibrosis (present at diagnosis): (1) age > 65 years, (2) hemoglobin < 10 g/dL, (3) leukocytes > 25 × 109/L, (4) peripheral blood blasts ≥ 1%, and (5) constitutional symptoms (weight loss > 10%, night sweats, or fevers).