Table 4.
Detailed molecular analysis of the Mannheim cohort of 190 patients with advanced SM
| Characteristics | Male (n = 127) |
Female (n = 63) |
P |
|---|---|---|---|
| Age, years; median (range) | 69 (25-90) | 64 (24-83) | 0.009 |
| WHO diagnosis, n (%) | |||
| ASM | 6 (5) | 10 (16) | 0.013 |
| SM-AHN | 106 (83) | 48 (76) | 0.243 |
| MCL (± AHN) | 15 (12) | 5 (8) | 0.464 |
| Leukemic transformationa, n (%) | 21 (17) | 12 (19) | 0.687 |
| Mast cell infiltration in BM, histology (%) | |||
| Median (range) | 30 (5-95) | 25 (5-100) | 0.616 |
| Serum tryptase, µg/L | |||
| Median (range) | 170 (4-1854) | 180 (5-1690) | 0.835 |
| Driver mutation, n (%) | |||
| KIT D816V | 119 (94) | 56 (89) | 0.263 |
| Other KIT mutations | 2 (2)b | 4 (6)c | 0.095 |
| No KIT mutations | 6 (5) | 3 (5) | 1.0 |
| Any additional somatic mutations, | |||
| n (%) ≥ 1 additional mutation(s) | 112 (88) | 44 (70) | 0.004 |
| S/A/Rd mutation(s), n (%) | |||
| ≥ 1 S/A/R mutation(s) | 80 (63) | 25 (40) | 0.003 |
| ≥ 2 S/A/R mutations | 35 (28) | 8 (13) | 0.027 |
| Aberrant karyotypee, n (%) | 18 (17) | 9 (19) | 1.0 |
| Follow-up, years | |||
| Median (range) | 2.1 (0-17) | 2.6 (0-21) | 0.083 |
| Death, n (%) | 69 (54) | 26 (41) | - |
| Overall survival, years | |||
| Median (95% CI) | 2.9 (1.9-3.9) | 4.6 (2.7-6.5) | 0.027 |
Abbreviations: AHN, associated hematologic neoplasm; ASM, aggressive systemic mastocytosis; BM, bone marrow; MCL, mast cell leukemia; WHO, World Health Organization.
a to secondary MCL (±AHN) or secondary SM-AML;
b KIT D816H, n = 1; KIT F522C, n = 1;
c KIT D816H, n = 2; KIT D816Y, n = 2;
d gene mutation(s) in SRSF2, ASXL1 and/or RUNX1 (S/A/R) panel;
e data available in n = 168.