Patient characteristics
| . | Total, N = 80 . | Additional mutation, n = 37 . | Only driver mutation, n = 43 . | P . |
|---|---|---|---|---|
| Initial presentation | ||||
| Female, n (%) | 50 (63) | 22 (59) | 28 (65) | .60 |
| PVT, n (%) | 52 (65) | 23 (62) | 29 (67) | .62 |
| Age at diagnosis, mean (range), y | 42 (17-73) | 44 (21-68) | 40 (17-73) | .13 |
| Hemoglobin, median (range), g/dL | 14.2 (8.6-19.5) | 14.3 (11.1-19.5) | 14 (8.6-17.9) | .11 |
| Hematocrit, median (range), %* | 43 (28-62) | 43 (35-62) | 42 (28-55) | .27 |
| WBC count, median (range), ×109/L* | 8.6 (3.5-34.9) | 9 (4-33.4) | 8.4 (3.5-34.9) | .83 |
| Platelet count, median (range), ×109/L* | 340 (136-2103) | 357 (153-1200) | 338 (136-2103) | .26 |
| Spleen size BCM, median (range), cm† | 2 (0-9) | 3 (0-8) | 2 (0-9) | .46 |
| MPN subtype and driver mutation, n (%) | ||||
| PV | 52 (65) | 25 (68) | 27 (62) | .65 |
| ET | 23 (29) | 9 (24) | 14 (33) | .65 |
| PMF | 5 (6) | 3 (8) | 2 (5) | .65 |
| JAK2 V617F/CALR, n | 76/4 | 34/3 | 42/1 | .33 |
| JAK2 allele burden, median (range), % | 14.5 (0.4-93) | 31 (0.4-93) | 11 (1-85) | <.01 |
| JAK2 allele burden ≥50%, n (%) | 16 (20) | 13 (35) | 3 (7) | <.01 |
| Treatment and outcomes | ||||
| Follow-up, median (range), y | 11 (0.3-37) | 12 (0.3-37) | 10 (0.9-35) | .19 |
| Cytoreductive treatment, n (%) | 75 (94) | 33 (89) | 42 (98) | .17 |
| Primary outcomes, n (%) | 10 (13) | 8 (22) | 2 (5) | .04 |
| Secondary myelofibrosis | 7 (9) | 6 (21) | 1 (2) | .04 |
| Acute leukemia | 2 (3) | 2 (5) | 0 | .21 |
| Death | 5 (6) | 4 (11)‡ | 1 (2)§ | .17 |
| Thrombosis, n (%) | ||||
| Associated thrombophilia | 14 (18) | 7 (19) | 7 (16) | .77 |
| Anticoagulant therapy | 78 (98) | 35 (95) | 43 (100) | .21 |
| Thrombosis recurrence | 12 (15) | 5 (14) | 7 (16) | .76 |
| . | Total, N = 80 . | Additional mutation, n = 37 . | Only driver mutation, n = 43 . | P . |
|---|---|---|---|---|
| Initial presentation | ||||
| Female, n (%) | 50 (63) | 22 (59) | 28 (65) | .60 |
| PVT, n (%) | 52 (65) | 23 (62) | 29 (67) | .62 |
| Age at diagnosis, mean (range), y | 42 (17-73) | 44 (21-68) | 40 (17-73) | .13 |
| Hemoglobin, median (range), g/dL | 14.2 (8.6-19.5) | 14.3 (11.1-19.5) | 14 (8.6-17.9) | .11 |
| Hematocrit, median (range), %* | 43 (28-62) | 43 (35-62) | 42 (28-55) | .27 |
| WBC count, median (range), ×109/L* | 8.6 (3.5-34.9) | 9 (4-33.4) | 8.4 (3.5-34.9) | .83 |
| Platelet count, median (range), ×109/L* | 340 (136-2103) | 357 (153-1200) | 338 (136-2103) | .26 |
| Spleen size BCM, median (range), cm† | 2 (0-9) | 3 (0-8) | 2 (0-9) | .46 |
| MPN subtype and driver mutation, n (%) | ||||
| PV | 52 (65) | 25 (68) | 27 (62) | .65 |
| ET | 23 (29) | 9 (24) | 14 (33) | .65 |
| PMF | 5 (6) | 3 (8) | 2 (5) | .65 |
| JAK2 V617F/CALR, n | 76/4 | 34/3 | 42/1 | .33 |
| JAK2 allele burden, median (range), % | 14.5 (0.4-93) | 31 (0.4-93) | 11 (1-85) | <.01 |
| JAK2 allele burden ≥50%, n (%) | 16 (20) | 13 (35) | 3 (7) | <.01 |
| Treatment and outcomes | ||||
| Follow-up, median (range), y | 11 (0.3-37) | 12 (0.3-37) | 10 (0.9-35) | .19 |
| Cytoreductive treatment, n (%) | 75 (94) | 33 (89) | 42 (98) | .17 |
| Primary outcomes, n (%) | 10 (13) | 8 (22) | 2 (5) | .04 |
| Secondary myelofibrosis | 7 (9) | 6 (21) | 1 (2) | .04 |
| Acute leukemia | 2 (3) | 2 (5) | 0 | .21 |
| Death | 5 (6) | 4 (11)‡ | 1 (2)§ | .17 |
| Thrombosis, n (%) | ||||
| Associated thrombophilia | 14 (18) | 7 (19) | 7 (16) | .77 |
| Anticoagulant therapy | 78 (98) | 35 (95) | 43 (100) | .21 |
| Thrombosis recurrence | 12 (15) | 5 (14) | 7 (16) | .76 |
BCM, below the costal margin; PMF, primary myelofibrosis; WBC, white blood cell count.
Missing data for 8 patients.
Missing data for 16 patients.
Death related to infection after refractory acute leukemia (n = 1), bleeding event after secondary myelofibrosis (n = 2), bleeding event after hepatic failure (n = 1).
Death related to stroke (n = 1).