Systemic mastocytosis (SM) with an associated hematological neoplasm (SM-AHN) constitutes about 40% of all patients with SM. AHN commonly includes myeloid neoplasms and chronic myelomonocytic leukemia (CMML) is seen in about 30% of these patients.
A 67-year-old male presented to hematologist with fatigue and significant weight loss. Abdominal ultrasound and computed tomography (CT) detected hepatosplenomegaly, abdominal lymphadenopathy, and ascites. He was anemic with leukocytosis and eosinophilia. Trephine biopsy showed > 30% of spindle-shaped mast cells. The KITD816V mutation was present. Serum tryptase level was elevated to 62 ng/mL. The patient was diagnosed with aggressive SM and received six cycles of cladribine with partial response. Three years later, he developed severe anemia. Eosinophilia and monocytosis (5.6 × 109/L) were demonstrated in blood film. Hepatosplenomegaly and abdominal lymphadenopathy were also present. Trephine biopsy did not demonstrate the presence of spindle-shaped mast cells, but dysplasia in erythroid and myeloid lineages was evident. The histological result of lymph node biopsy as well as blood and bone marrow findings were in line with CMML. He received hydroxyurea, but he transformed soon into fatal acute monocytic leukemia.
The prognosis of SM-AHN depends on AHN component. Leukemic transformation of AHN component may occur in a proportion of patients.
Myelodysplastic syndromes (MDSs) are a heterogeneous group of clonal myeloid neoplasms. Allogeneic stem cell transplantation (allo-SCT) remains the curative method for MDS treatment. Little is known about the monitoring of minimal residual disease (MRD) in patients with MDS after allo-SCT.
We aimed to evaluate the significance of leukemia-associated immunophenotypes (LAIPs) identified in acute myeloid leukemia (AML) for MRD monitoring in patients with MDS after allo-SCT.
Material and methods
Seven males and 4 females with a median age of 55 years were included. The diagnosis of MDS was established according to 2016 World Health Organization (WHO) criteria. The significance of eight LAIPs in bone marrow samples using multiparameter flow cytometry (MFC) was evaluated for MRD.
Eight patients were positive for several LAIPs before allo-SCT. The identified LAIPs included the presence of aberrant lymphoid antigens on myeloblasts and lack of CD33 expression on myeloblasts. All studied MDS patients were negative for LAIPs at Day +30 after the procedure. This was followed by full-donor chimerism in all cases. The Ogata score after allo-SCT decreased in all patients in whom it was indicative for MDS before allo-SCT.
MFC could be useful in monitoring MRD in MDS patients after allo-SCT. Further studies in this field are needed.