Table 2.
Baseline characteristics of MPN-AP/BP cohort at time of transformation
| Variable (%) | Whole cohort (N = 138) | Intensive (AML-type induction) (N = 81) |
Nonintensive (HMA or AzaVen) (N = 57) |
P value (intensive vs nonintensive) |
|---|---|---|---|---|
| Age at transformation, median [range], y | 64 [22-87] | 60 [22-76] | 70 [42-87] | <.001 |
| Sex | .16 | |||
| Male | 87 (63) | 47 (58) | 40 (70) | |
| Female | 51 (37) | 34 (42) | 17 (30) | |
| Transformation type | <.001 | |||
| AP | 34 (25) | 9 (11) | 25 (44) | |
| BP | 104 (75) | 72 (89) | 32 (56) | |
| Chronic MPN diagnosis∗ | .16 | |||
| PV/ET | 35 (25) | 23 (28) | 12 (21) | |
| MPN-U | 15 (11) | 12 (15) | 3 (5) | |
| PMF | 36 (26) | 20 (25) | 16 (28) | |
| PPV/PET-MF | 52 (38) | 26 (32) | 26 (46) | |
| Number of prior MPN treatments in chronic phase | N = 137 | N = 80 | N = 57 | .16 |
| 0-1 | 80 (58) | 51 (64) | 29 (51) | |
| ≥2 | 57 (42) | 29 (36) | 28 (49) | |
| ECOG | N = 126 | N = 74 | N = 52 | .03 |
| 0-1 | 106 (84) | 67 (91) | 39 (75) | |
| ≥2 | 20 (16) | 7 (9) | 13 (25) | |
| Palpable spleen length (BCM) at time of AP/BP | N = 126 | N = 71 | N = 55 | .80 |
| Not palpable | 47 (37) | 24 (34) | 23 (42) | |
| < 10 cm | 30 (24) | 17 (24) | 13 (24) | |
| ≥10 cm | 38 (30) | 23 (32) | 15 (27) | |
| Splenectomy | 11 (9) | 7 (10) | 4 (7) | |
| Laboratory parameters†, median (range) [number] | ||||
| Hb, g/L | 87 (51-177) [n = 132] | 87 (51-177) [n = 77] | 87 (51-134) [55] | .58 |
| WBC, ×109/L | 12.2 (1-213) [n = 134] | 12.8 (1.1-213) [n = 79] | 11.5 (1-126) [n = 55] | .56 |
| ANC, ×109/L | 3.8 (0-91) [n = 123] | 3.8 (0-91) [n = 70] | 3.6 (0.2-79) [n = 53] | .77 |
| Platelets, ×109/L | 90 (6-1918) [n = 133] | 73 (6-865) [n = 78] | 109 (13-1918) [n = 55] | .01 |
| PB blasts, % | 16 (0-83) [n = 134] | 19.5 (0-83) [n = 78] | 12 (0-83) [n = 56] | .03 |
| BM blasts, % | 25 (3-90) [n = 113] | 31 (4-90) [n = 67] | 20 (3-89) [n = 46] | .03 |
| LDH, U/L | 598 (43-5893) [n = 127] | 681 (144-5893) [n = 74] | 553 (43-4000) [n = 53] | .15 |
| Albumin, g/L | 39 (27-47) [n = 124] | 38 (27-47) [n = 74] | 42 (30-45) [n = 50] | .03 |
| ELN 2022 RISK | N = 121 | N = 69 | N = 52 | .14 |
| Adverse | 72 (60) | 37 (54) | 35 (67) | |
| Nonadverse | 49 (40) | 32 (46) | 17 (33) | |
| MPN driver mutations | N = 101 | N = 53 | N = 48 | .29 |
| JAK2/MPL | 66 (65) | 31 (58) | 35 (73) | |
| CALR | 12 (12) | 7 (13) | 5 (10) | |
| Triple negative | 23 (23) | 15 (29) | 8 (17) | |
| Genes mutated in ≥5% of patients | N = 101 | N = 53 | N = 48 | |
| ASXL1 | 29 (29) | 10 (19) | 19 (40) | .03 |
| TET2 | 26 (26) | 18 (34) | 8 (17) | .07 |
| SRSF2 | 26 (26) | 10 (19) | 16 (33) | .11 |
| IDH1/2 | 22 (22) | 11 (21) | 11 (23) | .81 |
| TP53 | 21 (21) | 13 (25) | 8 (17) | .46 |
| RUNX1 | 19 (19) | 8 (15) | 11 (23) | .45 |
| DNMT3A | 16 (16) | 7 (13) | 9 (19) | .59 |
| NRAS | 13 (13) | 5 (9) | 8 (17) | .38 |
| EZH2 | 10 (10) | 4 (8) | 6 (12) | .51 |
| STAG2 | 12 (12) | 5 (9) | 7 (15) | .54 |
| PTPN11 | 7(7) | 1 (2) | 6 (12) | .05 |
| CEBPA | 6 (6) | 4 (8) | 2 (4) | .68 |
| SETBP1 | 6 (6) | 4 (8) | 2 (4) | .68 |
| U2AF1 | 6 (6) | 0 | 6 (12) | .01 |
| CBL | 5 (5) | 1 (2) | 4 (8) | .19 |
| SF3B1 | 6 (6) | 4 (8) | 2 (4) | .68 |
| ZRSR2 | 5 (5) | 2 (4) | 3 (6) | .67 |
| Mutations by pathway | N = 101 | N = 53 | N = 48 | |
| JAK-STAT pathway‡ | 80 (79) | 38 (72) | 42 (88) | .08 |
| RAS pathway§ | 23 (23) | 10 (19) | 13 (27) | .4 |
| RNA splicing‖ | 40 (40) | 15 (28) | 25 (52) | .02 |
| Epigenetic regulation¶ | 67 (66) | 35 (66) | 32 (67) | 1.0 |
| Transcription factors# | 32 (32) | 15 (28) | 17 (35) | .5 |
| Number of mutations | N = 101 | N = 53 | N = 48 | .04 |
| 0-1 | 17 (17) | 12 (23) | 5 (10) | |
| 2-3 | 36 (36) | 22 (42) | 14 (29) | |
| ≥4 | 48 (48) | 19 (36) | 29 (60) |
BCM, below costal margin; LDH, lactate dehydrogenase; MPN-U, MPN unclassifiable; PET-MF, post–ET MF; PMF, primary MF; PPV-MF, post–PV MF. Bold values are statistically significant.
∗
Before leukemic transformation.
†
One patient received decitabine and the remainder received azacitidine.
‡
JAK2, MPL, CALR, CSF3R.
§
CBL, NRAS, PTPN11, KIT, KRAS.
‖
SF3B1, SRSF2, U2AF1, ZRSR2.
¶
ASXL1, BCOR, DNMT3A, EZH2, IDH1/2, SETBP1, TET2.
#
CEBPA, CUX1, ETV6, GATA2, IKZF1, PHF6, RUNX1, WT1.