Table 4.
Clinical, laboratory, genetic, and outcome characteristics of patients with advanced SM with normal and increased bone mineral density
| Characteristics | Increased BMD (n = 24) | Normal BMD (n = 8) | P |
|---|---|---|---|
| Age (years) | |||
| Median | 77 | 68 | 0.043 |
| Range | 53–81 | 28–82 | |
| Sex, n (%) | |||
| Men | 15 (63) | 6 (75) | NS |
| Women | 9 (37) | 2 (25) | NS |
| WHO classification | |||
| ASM, n (%) | 3 (12) | 1 (12) | NS |
| SM-AHN, n (%) | 17 (71) | 7 (88) | NS |
| MCL ± AHN, n (%) | 4 (17) | 0 | NS |
| Hemoglobin (g/dL) | |||
| Median | 10.5 | 12.9 | NS |
| Range | 7.9–14.2 | 7.5–14.8 | |
| < 10 g/dL, n (%) | 11 (46) | 2 (25) | NS |
| Platelets (× 109/L) | |||
| Median | 111 | 238 | 0.041 |
| Range | 39–312 | 45–577 | |
| < 100 × 109/L, n (%) | 11 (46) | 2 (25) | NS |
| Mast cell infiltration in BM histology (%) | |||
| Median | 50 | 10 | 0.002 |
| Range | 5–95 | 5–30 | |
| Serum tryptase (µg/L) | |||
| Median | 262 | 62 | 0.003 |
| Range | 30–1250 | 14–230 | |
| Alkaline phosphatasea (U/L) | |||
| Median | 238 | 74 | < 0.0001 |
| Range | 76–756 | 55–173 | |
| > UNL, n (%) | 21 (88) | 1 (13) | < 0.001 |
| KIT D816V EAB (%) | |||
| Median | 30 | 4.3 | 0.046 |
| Range | 1–50 | 1–64 | |
| S/A/R mutation(s) | |||
| 1 mutation, n (%) | 19 (75) | 4 (50) | NS |
| ≥ 2 mutations, n (%) | 10 (42) | 0 | 0.035 |
| Follow-up (years) | |||
| Median | 3.6 | 5.5 | NS |
| Range | 0.1–14.5 | 0.8–19.3 | |
| Overall survival (years) | |||
| Median | 3.6 | NR | 0.031 |
| 95% CI | 2.1–5.1 | ||
| Death, n (%) | 19 (79) | 2 (25) | |
AdvSM advanced systemic mastocytosis; AHN associated hematologic neoplasm; ASM aggressive SM; BM bone marrow; BMD bone mineral density; CI confidence interval; EAB expressed allele burden; MCL mast cell leukemia; NR not reached; NS non-significant; S/A/R one or more gene mutations in SRSF2, ASXL1, RUNX1; UNL upper normal limit
aThe comparison between normal BMD and increased BMD regarding median surivval