Table 1.

Baseline characteristics of patients

CharacteristicsOverall population (N = 10)
Median age (range), y72.5 (40-84)
Female sex, n (%)6 (60)
ECOG performance status, n (%)
 0-17 (70)
 2-33 (30)
Median number of prior therapies (range), n0.5 (0-2)
Number of prior therapies per patient, n (%)
 05 (50)
 14 (40)
 21 (10)
Type of prior therapy, n (%)
 Splenectomy3 (30)
 Cladribine3 (30)
 Midostaurin1 (10)
 Imatinib1 (10)
 Decitabine*1 (10)
Clinicopathologic diagnosis, n (%)
 ASM3 (30)
 SM-AHN5 (50)
  CMML-13 (30)
  MDS/MPN-U1 (10)
  CEL, NOS1 (10)
 MCL2 (20)
  CMML-11 (10)
Mutation status, n (%)
 KIT D816V mutation10 (100)
Median number of IWG-MRT-ECNM organ damage findings (range), n1 (1-3)
Number of IWG-MRT-ECNM organ damage findings per patient, n (%)
 16 (60)
 22 (20)
 32 (20)
Types of IWG-MRT-ECNM organ damage findings, n (%)
 Elevated alkaline phosphatase5 (50)
 Symptomatic splenomegaly3 (30)
 Anemia4 (40)
  Transfusion-dependent2 (20)
  Transfusion-independent2 (20)
 Thrombocytopenia4 (40)
  Transfusion-dependent2 (20)
  Transfusion-independent2 (20)
 Neutropenia1 (10)
 Ascites1 (10)
Median serum tryptase (range), ng/mL295 (81-903)
Median bone marrow core biopsy mast cell burden (range), % involvement55 (15-60)
Median bone marrow mast cell CD30+ expression (range), %70 (29-96)
  • * AHN-directed therapy for MDS/MPN-U.

  • For the full listing and definitions of eligible organ damage criteria, please see the IWG-MRT-ECNM consensus guidelines.29

  • Measured via tryptase, CD117, and CD25 immunohistochemistry staining on the core biopsy specimen.

  • Measured via multiparametric FCM methods using anti-BerH83 antibody on aspirate specimen.

  • CEL, chronic eosinophilic leukemia, not otherwise specified; CMML-1, chronic myelomonocytic leukemia, <10% blasts; ECOG, Eastern Cooperative Oncology Group; KIT, CD117, c-Kit receptor; MCL, mast cell leukemia; MDS/MPN-U, myelodysplastic/myeloproliferative neoplasm, unclassifiable; MPN-SAF, Myeloproliferative Neoplasm Symptom Assessment Form.