Clinical-biological features and outcome of ISM patients from the discovery series (n = 200) grouped according to their gene mutational profile and the pattern of BM involvement of hematopoiesis by the KIT mutation
| Clinical and biological features . | Overall gene mutational profile . | BM KIT mutational profile . | TOTAL (N = 200) . | ||||
|---|---|---|---|---|---|---|---|
| Isolated KIT mutation (n = 165) . | ≥1 Mutation other than KIT (n = 35) . | P . | KIT D816V < 1% VAF (n = 113) . | KIT D816V ≥ 1% VAF (n = 78) . | P . | ||
| Age at diagnosis, y* | 43 (0-76) | 50 (30-66) | .003 | 41 (16-64) | 49 [0-76] | <.001 | 44 (0-76) |
| Sex (female) | 81/165 (49) | 16/35 (46) | NS | 52/113 (46) | 42/78 (54) | NS | 97/200 (49) |
| Skin lesions | 127/165 (77) | 24/35 (69) | NS | 77/113 (68) | 72/78 (92) | <.001 | 151/200 (76) |
| Organomegalies: | |||||||
| Hepatomegaly | 11/161 (6.8) | 4/35 (11) | NS | 4/111 (3.6) | 9/77 (12) | .03 | 15/196 (7.7) |
| Splenomegaly | 9/161 (5.6) | 1/35 (2.9) | NS | 2/111 (1.8) | 7/77 (9.1) | .02 | 10/196 (5.1) |
| Osteolysis/osteoporosis (without bone fractures) | 24/139 (17) | 5/29 (16) | NS | 13/95 (13.7) | 15/70 (21.4) | NS | 29/170 (17) |
| Mild cytopenia | 10/162 (6.2) | 3/34 (8.8) | NS | 6/111 (5.4) | 7/76 (9.2) | NS | 13/196 (6.6) |
| Hemoglobin (g/L)* | 142 (100-190) | 142 (100-170) | NS | 145 (100-190) | 138 (100-160) | <.001 | 142 (100-190) |
| ANC (×109/L)* | 3.5 (1.6-10) | 3.9 (2.1-9.5) | NS | 3.8 (1.6-10) | 3.3 (1.6-7.4) | NS | 3.6 (1.6-10) |
| Platelets (×109/L)* | 233 (100-480) | 240 (102-344) | NS | 240.5 (100-480) | 228 (102-451) | NS | 234 (100-480) |
| BM MC (%) by flow cytometry | 0.1 (0.001-15.5) | 0.26 (0.02-3.7) | .006 | 0.06 (0.002-1.2) | 0.3 (0.001-15.5) | <.001 | 0.1 (0.001-15.5) |
| BM aggregates ≥30% | 0/165 (0) | 0/35 (0) | NS | 0/113 (0) | 0/78 (0) | NS | 0/200 (0) |
| sBT (µg/L)* | 32.4 (4-1298) | 39.5 (11-362) | NS | 27.2 (4-210) | 59.9 (11-1298) | <.001 | 32.9 (4-1298) |
| ≥200 µg/L | 11/164 (6.7) | 3/35 (8.6) | NS | 1/113 (0.9) | 13/77 (17) | <.001 | 14/199 (7) |
| LDH (U/L)* | 256 (112-530) | 253 (97-419) | NS | 270 (97-421) | 243 (112-530) | .006 | 256 (97-530) |
| <230 U/L | 42/158 (26) | 8/32 (25) | NS | 22/110 (20) | 27/71 (38) | .008 | 50/190 (26) |
| SAP (U/L)* | 63 (6-290) | 79.5 (14-233) | .006 | 63 (31-135) | 76 (6-290) | .008 | 66 (6-290) |
| ≥140 U/L | 6/158 (3.8) | 1/31 (3.2) | NS | 0/113 (0) | 6/69 (8.6) | .002 | 7/189 (3.7) |
| sβ2M (µg/mL)* | 1.6 (0.9-4.3) | 1.9 (1.2-6.9) | .02 | 1.6 (1.1-2.4) | 2 (0.9-6.9) | <.001 | 1.7 (0.9-6.9) |
| ≥2.5 µg/mL | 10/157 (6.3) | 7/33 (21) | .006 | 0/113 (0) | 20/71 (28.2) | <.001 | 17/187 (9) |
| IgE (KU/L)* | 19.3 (2-2395) | 27.4 (2-262) | NS | 29 (2-1364) | 11.2 (2-2395) | .001 | 20.7 (2-2395) |
| ≥100 KU/L | 20/145 (14) | 2/30 (6.7) | NS | 15/101 (15) | 5/68 (7.4) | NS | 22/176 (13) |
| Progression to SSM or advSM | 8/165 (4.8) | 6/35 (17) | .008 | 0/113 (0) | 14/78 (18) | <.001 | 14/200 (7) |
| Deaths | 0/165 (0) | 4/35 (11.4) | <.001 | 0/113 (0) | 4/78 (5.1) | .02 | 4/200 (2) |
| Clinical and biological features . | Overall gene mutational profile . | BM KIT mutational profile . | TOTAL (N = 200) . | ||||
|---|---|---|---|---|---|---|---|
| Isolated KIT mutation (n = 165) . | ≥1 Mutation other than KIT (n = 35) . | P . | KIT D816V < 1% VAF (n = 113) . | KIT D816V ≥ 1% VAF (n = 78) . | P . | ||
| Age at diagnosis, y* | 43 (0-76) | 50 (30-66) | .003 | 41 (16-64) | 49 [0-76] | <.001 | 44 (0-76) |
| Sex (female) | 81/165 (49) | 16/35 (46) | NS | 52/113 (46) | 42/78 (54) | NS | 97/200 (49) |
| Skin lesions | 127/165 (77) | 24/35 (69) | NS | 77/113 (68) | 72/78 (92) | <.001 | 151/200 (76) |
| Organomegalies: | |||||||
| Hepatomegaly | 11/161 (6.8) | 4/35 (11) | NS | 4/111 (3.6) | 9/77 (12) | .03 | 15/196 (7.7) |
| Splenomegaly | 9/161 (5.6) | 1/35 (2.9) | NS | 2/111 (1.8) | 7/77 (9.1) | .02 | 10/196 (5.1) |
| Osteolysis/osteoporosis (without bone fractures) | 24/139 (17) | 5/29 (16) | NS | 13/95 (13.7) | 15/70 (21.4) | NS | 29/170 (17) |
| Mild cytopenia | 10/162 (6.2) | 3/34 (8.8) | NS | 6/111 (5.4) | 7/76 (9.2) | NS | 13/196 (6.6) |
| Hemoglobin (g/L)* | 142 (100-190) | 142 (100-170) | NS | 145 (100-190) | 138 (100-160) | <.001 | 142 (100-190) |
| ANC (×109/L)* | 3.5 (1.6-10) | 3.9 (2.1-9.5) | NS | 3.8 (1.6-10) | 3.3 (1.6-7.4) | NS | 3.6 (1.6-10) |
| Platelets (×109/L)* | 233 (100-480) | 240 (102-344) | NS | 240.5 (100-480) | 228 (102-451) | NS | 234 (100-480) |
| BM MC (%) by flow cytometry | 0.1 (0.001-15.5) | 0.26 (0.02-3.7) | .006 | 0.06 (0.002-1.2) | 0.3 (0.001-15.5) | <.001 | 0.1 (0.001-15.5) |
| BM aggregates ≥30% | 0/165 (0) | 0/35 (0) | NS | 0/113 (0) | 0/78 (0) | NS | 0/200 (0) |
| sBT (µg/L)* | 32.4 (4-1298) | 39.5 (11-362) | NS | 27.2 (4-210) | 59.9 (11-1298) | <.001 | 32.9 (4-1298) |
| ≥200 µg/L | 11/164 (6.7) | 3/35 (8.6) | NS | 1/113 (0.9) | 13/77 (17) | <.001 | 14/199 (7) |
| LDH (U/L)* | 256 (112-530) | 253 (97-419) | NS | 270 (97-421) | 243 (112-530) | .006 | 256 (97-530) |
| <230 U/L | 42/158 (26) | 8/32 (25) | NS | 22/110 (20) | 27/71 (38) | .008 | 50/190 (26) |
| SAP (U/L)* | 63 (6-290) | 79.5 (14-233) | .006 | 63 (31-135) | 76 (6-290) | .008 | 66 (6-290) |
| ≥140 U/L | 6/158 (3.8) | 1/31 (3.2) | NS | 0/113 (0) | 6/69 (8.6) | .002 | 7/189 (3.7) |
| sβ2M (µg/mL)* | 1.6 (0.9-4.3) | 1.9 (1.2-6.9) | .02 | 1.6 (1.1-2.4) | 2 (0.9-6.9) | <.001 | 1.7 (0.9-6.9) |
| ≥2.5 µg/mL | 10/157 (6.3) | 7/33 (21) | .006 | 0/113 (0) | 20/71 (28.2) | <.001 | 17/187 (9) |
| IgE (KU/L)* | 19.3 (2-2395) | 27.4 (2-262) | NS | 29 (2-1364) | 11.2 (2-2395) | .001 | 20.7 (2-2395) |
| ≥100 KU/L | 20/145 (14) | 2/30 (6.7) | NS | 15/101 (15) | 5/68 (7.4) | NS | 22/176 (13) |
| Progression to SSM or advSM | 8/165 (4.8) | 6/35 (17) | .008 | 0/113 (0) | 14/78 (18) | <.001 | 14/200 (7) |
| Deaths | 0/165 (0) | 4/35 (11.4) | <.001 | 0/113 (0) | 4/78 (5.1) | .02 | 4/200 (2) |
Unless otherwise noted, results are expressed as number of cases (%). Per definition, all (ISM) cases showed hemoglobin levels ≥ 100 g/L, neutrophil counts ≥ 1000/µL, and platelet counts ≥ 100 × 103/µL.
LDH, lactate dehydrogenase; NS, not statistically significant.
Data are median (range).