Statistical analysis of the expression of p-Btk and p-Lyn as assessed by IHC in ISM and advanced SM
| Patient cohort . | Lyn . | p-LynTyr507 . | p-LynTyr396 . | Btk . | p-BtkTyr551 . |
|---|---|---|---|---|---|
| ISM (tryptase, < 200 ng/mL) | 11/15 (73.3%) | 6/15 (40%) | 3/6 (50%) | 14/16 (87.5%) | 1/16 (6.3%) |
| ISM (tryptase, > 200 ng/mL) | 2/2 (100%) | 1/2 (50%) | 1/2 (50%) | 3/3 (100%) | 2/3 (66.7%) |
| ISM (all) | 13/17 (76.5%) | 7/17 (41.2%) | 4/8 (50%) | 17/19 (89.5%) | 3/19 (15.8%) |
| SSM | 3/4 (75%) | 2/4 (50%) | 4/4 (100%) | 3/4 (75%) | 3/4 (75%) |
| ASM/MCL | 6/6 (100%) | 5/6 (83.3%) | 5/5 (100%) | 6/6 (100%) | 5/6 (83.3%) |
| Advanced SM* | 9/10 (90%) | 7/10 (70%) | 9/9 (100%) | 9/10 (90%) | 8/10 (80%) |
| Patient cohort . | Lyn . | p-LynTyr507 . | p-LynTyr396 . | Btk . | p-BtkTyr551 . |
|---|---|---|---|---|---|
| ISM (tryptase, < 200 ng/mL) | 11/15 (73.3%) | 6/15 (40%) | 3/6 (50%) | 14/16 (87.5%) | 1/16 (6.3%) |
| ISM (tryptase, > 200 ng/mL) | 2/2 (100%) | 1/2 (50%) | 1/2 (50%) | 3/3 (100%) | 2/3 (66.7%) |
| ISM (all) | 13/17 (76.5%) | 7/17 (41.2%) | 4/8 (50%) | 17/19 (89.5%) | 3/19 (15.8%) |
| SSM | 3/4 (75%) | 2/4 (50%) | 4/4 (100%) | 3/4 (75%) | 3/4 (75%) |
| ASM/MCL | 6/6 (100%) | 5/6 (83.3%) | 5/5 (100%) | 6/6 (100%) | 5/6 (83.3%) |
| Advanced SM* | 9/10 (90%) | 7/10 (70%) | 9/9 (100%) | 9/10 (90%) | 8/10 (80%) |
Based on the results obtained by IHC shown in Table 3, the percentages of patients expressing Lyn, p-LynTyr507, Btk, and p-BtkTyr551 were calculated.
ISM indicates indolent SM; SM, systemic mastocytosis; SSM: smoldering SM; ASM, aggressive SM; and MCL, mast cell leukemia.
Advanced SM includes SSM, ASM, and MCL. As assessed by statistical analysis (χ2 test), the difference in p-Btk and p-LynTyr396 expression in ISM (all ISM) and advanced SM (SSM/ASM/MCL) was significant (p-Btk: 15.8% vs 80%, P < .05; p-LynTyr396: 50% vs 100%, P < 0.05). Expression of p-LynTyr507 was also detected more frequently in advanced SM, but statistical significance was not reached.