Mutations in the calreticulin gene, CALR, have recently been discovered in subsets of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF). We investigated Korean patients with ET and PMF to determine the prevalence, and clinical and laboratory correlations of CALR/JAK2/MPL mutations. Among 84 ET patients, CALR mutations were detected in 23 (27.4%) and were associated with higher platelet counts (P=0.006) and lower leukocyte counts (P=0.035) than the JAK2 V617F mutation. Among 50 PMF patients, CALR mutations were detected in 11 (22.0%) and were also associated with higher platelet counts (P=0.035) and trended to a lower rate of cytogenetic abnormalities (P=0.059) than the JAK2 V617F mutation. By multivariate analysis, triple-negative status was associated with shorter overall survival (HR, 7.0; 95% CI, 1.6-31.1, P=0.01) and leukemia-free survival (HR, 6.3; 95% CI, 1.8-22.0, P=0.004) in patients with PMF. The type 1 mutation was the most common (61.1%) type among all patients with CALR mutations, and tended toward statistical predominance in PMF patients. All 3 mutations were mutually exclusive and were never detected in patients with other myeloid neoplasms showing thrombocytosis. CALR mutations characterize a distinct group of Korean ET and PMF patients. Triple-negative PMF patients in particular have an unfavorable prognosis, which supports the idea that triple-negative PMF is a molecularly high-risk disease.
CALR; JAK2 V617F; MPL; Thrombocythemia, Essential; Primary Myelofibrosis
The presence of significant dysplasia in bone marrow (BM) aspirates helps to distinguish between hypocellular myelodysplastic syndrome (hMDS) and aplastic anemia (AA). Occasionally, diluted BM aspirates make it difficult to recognize dysplastic changes and can also negatively affect the detection of cytogenetic abnormalities in hMDS. We evaluated the usefulness of CD34 and p53 immunoreactivity for discriminating between hMDS and AA and for estimating survival outcomes in hMDS patients.
BM clot section (BMC) or BM biopsy (BMB) specimens were obtained from 64 hMDS/AA patients (33 with hMDS and 31 with AA) and seven controls. Immunohistochemical (IHC) staining for CD34 and p53 was performed by using the EnVision detection system (Dako, Denmark). We compared the results of IHC staining, BM findings, and chromosomal analyses, and determined overall survival outcomes.
The number of CD34- and p53-positive BM cells was higher among the patients with hMDS than among the patients with AA (P<0.001 and P=0.001, respectively). hMDS patients with increased CD34-positive cells had significantly poorer survival outcomes compared with those with normal number of CD34-positive cells (P=0.013).
CD34 and p53 IHC stains of BMC or BMB provide useful information for differentiating between hMDS and AA. CD34 IHC staining of BMC or BMB also provides useful information for estimating survival outcomes in hMDS patients.
Hypocellular myelodysplastic syndrome; Aplastic anemia; Immunohistochemistry; CD34; p53
Due to its strong correlation with the pathophysiology of many diseases, information about human red blood cells (RBCs) has a crucial function in hematology. Therefore, measuring and understanding the morphological, chemical, and mechanical properties of individual RBCs is a key to understanding the pathophysiology of a number of diseases in hematology, as well as to opening up new possibilities for diagnosing diseases in their early stages. In this study, we present the simultaneous and quantitative measurement of the morphological, chemical, and mechanical parameters of individual RBCs employing optical holographic microtomography. In addition, it is demonstrated that the correlation analyses of these RBC parameters provide unique information for distinguishing and understanding diseases.
Therapy-related AML (t-AML) occurs as a late complication of chemotherapy administered to treat a prior disorder. Prognostic factors affecting the clinical outcome in t-AML have not yet been clearly defined; therefore, we evaluated these factors in this study.
Forty-eight patients diagnosed with t-AML within the past 10 years were enrolled, and their chemotherapy regimens categorized into 4 groups: alkylating agents (AK) only, topoisomerase II inhibitors (TI) and AK, TI only, and others. The prognostic factors affecting clinical outcome were evaluated.
Five (10.4%), 21 (43.8%), 9 (18.8%), and 13 (27.0%) patients were treated with AK only, AK and TI, TI only, and others, respectively. Patients with an AML M3 phenotype showed significantly longer overall survival (OS; 55.1 vs. 14.3 months, P=0.040) and disease-free survival (DFS; 61.2 vs. 17.5 months, P=0.049) than other phenotypes. In contrast, patients with a complex karyotype showed significantly shorter OS (7.9 vs. 31.3 months, P=0.008) and DFS (9.5 vs. 38.6 months, P=0.046); additionally, patients with chromosome 5 or 7 abnormalities showed significantly shorter OS (9.1 vs. 30.7 months, P=0.011) than other phenotypes. Only the presence of a complex karyotype or AML M3 phenotype retained prognostic impact in a multivariate analysis.
Only the AML M3 phenotype was identified as having a good prognosis, and this might suggest that it exhibits unique clinical features in t-AML patients. Moreover, our findings indicated that karyotype was the strongest prognostic indicator and predicted a poor prognosis for t-AML patients with a complex karyotype.
Prognosis; Therapy; Related; AML
We aimed to evaluate the feasibility of using the allele burden of Janus kinase 2 (JAK2) V617F as a criterion for discriminating 3 subtypes of Philadelphia chromosome-negative myeloproliferative neoplasm (Ph-MPN): polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF).
We collected 70 peripheral blood (PB) and 81 bone marrow (BM) samples from patients diagnosed with Ph-MPN. Real-time quantitative PCR (RQ-PCR) and Amplification Refractory Mutation System (ARMS) assays were performed for each sample. We compared the allele burden of JAK2 V617F for each subtype of Ph-MPN and determined the concordance rates of the results between the 2 tests.
The JAK2 V617F allele burden differed significantly among the 3 disease categories in both PB (P=0.045) and BM (P=0.011) samples. Subsequent subgroup analysis revealed that the median allele burden of JAK2 V617F for ET (21.71% for PB and 24.95% for BM) was significantly lower than that for PV (56.88% for PB, P=0.047; 72.66% for BM, P=0.003) and PMF (56.16% for PB, P=0.050; 59.04% for BM, P=0.049). Concordance rate between the RQ-PCR and ARMS data was 90.7%. Of the 14 discrepant cases, 12 were RQ-PCR(+)/ARMS(-) and 2 were RQ-PCR(-)/ARMS(+).
The allele burden of JAK2 V617F was significantly lower for ET than that for PV or PMF in both PB and BM samples. The JAK2 V617F allele burden is a diagnostic tool for differentiating PV or PMF from ET.
Allele; Discrimination; Janus Kinase 2; Mutation; Myeloproliferative disorders; Real-time polymerase chain reaction
We report here a case of a 59-yr-old man with CD4+ T-cell large granular lymphocytic leukemia (T-LGL). Peripheral blood examination indicated leukocytosis (45×109 cells/L) that consisted of 34% neoplastic lymphoid cells. Other laboratory results indicated no specific abnormalities except for serum antinuclear antibody titer (1:640), glucose (1.39 g/L), and hemoglobin A1c (7.7%) levels. Computed tomography indicated multiple small enlarged lymph nodes (<1 cm in diameter) in both the axillary and inguinal areas, a cutaneous nodule (1.5 cm in diameter) in the left suboccipital area, and mild hepatosplenomegaly. Bone marrow examination revealed hypercellular marrow that consisted of 2.4% neoplastic lymphoid cells. The neoplastic lymphoid cells exhibited a medium size, irregularly shaped nuclei, a moderate amount of cytoplasm, and large granules in the cytoplasm. Immunohistochemical analysis indicated CD3+, CD4+, T-cell receptor βF1+, granzyme B+, and TIA1+. Flow cytometric analysis of the neoplastic lymphoid cells revealed CD3+, cytoplasmic CD3+, CD4+, and CD7+. Cytogenetic analysis indicated an abnormal karyotype of 46,XY,inv(3)(p21q27),t(12;17)(q24.1;q21),del(13)(q14q22)/46,XY. The patient was diagnosed with CD4+ T-LGL and received chemotherapy (10.0 mg methotrexate). This is the second case of CD4+ T-LGL that has been reported in Korea.
CD4+ T-LGL skin lesion; Leukocytosis
Multiparametric flow cytometry (MFC) allows discrimination between normal and neoplastic plasma cells (NeoPCs) within the bone marrow plasma cell (BMPC) compartment. This study sought to characterize immunophenotypes and quantitate the proportion of NeoPCs in BMPCs to diagnose plasma cell myeoma (PCM) and evaluate the prognostic impact of this method. We analyzed the MFC data of the bone marrow aspirates of 76 patients with PCM and 33 patients with reactive plasmacytosis. MFC analysis was performed using three combinations: CD38/CD138/-/CD45; CD56/CD20/CD138/CD19; and CD27/CD28/CD138/CD117. The plasma cells of patients with reactive plasmacytosis demonstrated normal immunophenotypic patterns. Aberrant marker expression was observed in NeoPCs, with negative CD19 expression observed in 100% of cases, CD56+ in 73.7%, CD117+ in 15.2%, CD27- in 10.5%, CD20+ in 9.2%, and CD28+ in 1.3%. In PCM patients, more than 20% of NeoPCs/BMPCs were significantly associated with factors suggestive of poor clinical outcomes. Patients who were CD27- or CD56+/CD27-, demonstrated shorter overall survival than patients of other CD56/CD27 combinations. Our results support the clinical value of immunophenotyping and quantifying NeoPCs in PCM patients. This strategy could help to reveal poor prognostic categories and delineate surrogate markers for risk stratification in PCM patients.
Multiple Myeloma; Flow Cytometry; Immunophenotyping; Neoplastic Cells; Plasma Cells
In up to 40% of systemic mastocytosis (SM) cases, an associated clonal hematological non-mast cell lineage disease such as AML is diagnosed before, simultaneously with, or after the diagnosis of SM. A 40-yr-old man was diagnosed with AML with t(8;21)(q22;q22). Mast cells were not noted at diagnosis, but appeared as immature forms at relapse. After allogeneic hematopoietic stem cell transplantation (HSCT), leukemic myeloblasts were not observed; however, neoplastic metachromatic blasts strikingly proliferated during the state of bone marrow aplasia, and finally, aleukemic mast cell leukemia developed. As the disease progressed, we observed serial morphologic changes from immature mast cells with myeloblasts to only metachromatic blasts and atypical mast cells as mast cell leukemia; FISH analysis showed that the neoplastic mast cells originated from the same clone as the leukemic myeloblasts of AML.
Systemic mastocytosis; Acute myeloid leukemia; Aleukemic mast cell leukemia; Allogeneic hematopoietic stem cell transplantation
The prognostic impact of the presence of differentiating neuroblasts in bone marrow (BM) remains unclear in BM metastatic neuroblastoma (NB). We aimed to identify the prognostic impact of differentiating neuroblasts in BM at diagnosis and after chemotherapy.
A total of 51 patients diagnosed with BM metastatic NB at Asan Medical Center between January 1990 and July 2005 were enrolled. BM histology and laboratory data along with overall survival (OS) were compared with regard to the differentiation status of neuroblasts in BM at diagnosis and after chemotherapy.
Among the 51 patients, 13 (25.5%) exhibited differentiating neuroblasts in BM at diagnosis and 17/51 (33.3%) exhibited them after chemotherapy. The only significant difference among patient groups was the improved OS in patients with differentiated neuroblasts in BM at diagnosis (P=0.021). In contrast, the differentiation status of neuroblasts in BM after chemotherapy did not affect OS (P=0.852).
Our study is the first report describing the presence of differentiating neuroblasts in BM. The presence of differentiating neuroblasts in BM at diagnosis may be a favorable prognostic factor for patients with BM metastatic NB; however, the same phenomenon after chemotherapy is irrelevant to prognosis.
Differentiating neuroblasts; Neuroblastoma; Bone marrow; Metastasis; Prognosis
Flow cytometric immunophenotyping has been used to identify neoplastic plasma cell populations in patients with multiple myeloma (MM). Previous reports have described the use of several antigens, including CD38, CD138, CD56, CD117, CD52, CD19 and CD45, to distinguish distinct populations of plasma cells. The aim of this study was to evaluate a simplified immunophenotyping panel for MM analysis.
A total of 70 patients were enrolled in the study, 62 of which were newly diagnosed with MM (untreated), whereas the remaining 8 were undergoing bone marrow assessment as part of follow-up after treatment (treated). Treated cases included 3 patients with relapse and 5 patients with persistence of MM. Multiparametric flow cytometric immunophenotyping was performed using monoclonal antibodies against CD56, CD19, CD138 (CD38), and CD45.
In differential counts, plasma cells in bone marrow (BM) accounted for 3.6-93.2% of the total nucleated cell count. The positive expression rates of CD56, CD19, CD138, and CD45 in neoplastic myeloma cells were 83.9%, 0%, 98.4%, and 37.1%, respectively, among the 62 untreated cases, and 75.0%, 0%, 87.5%, and 37.5%, respectively, among the 8 treated cases. CD19 expression of neoplastic plasma cells was negative in both untreated and treated cases.
The simplified immunophenotyping panel, CD56/CD19/CD138(CD38)/CD45, is useful for distinguishing neoplastic myeloma cells from reactive plasma cells in clinical practice. In addition, CD19 represents the most valuable antigen for identifying neoplastic myeloma cells in patients with MM.
Multiple myeloma; Flow cytometry; Immunophenotyping; Neoplastic plasma cells; CD19 negativity
Multiplex reverse transcription polymerase chain reaction (mRT-PCR) has recently emerged as an alternative to cytogenetics. We designed and used simplified mRT-PCR system as a molecular screen for acute leukemia. Fifteen fusion transcripts were included: BCR-ABL1, PML-RARA, ZBTB16-RARA, RUNX1-RUNX1T1, CBFB-MYH11, DEK-NUP214, TCF3-PBX1, ETV6-RUNX1, MLL-AFF1, MLL-MLLT4, MLL-MLLT3, MLL-MLLT10, MLL-ELL, MLL-MLLT1, and MLL-MLLT6. A total of 121 diagnostic acute leukemia specimens were studied, comparing the mRT-PCR system with standard cytogenetics. Fifty-six cases (46.3%) had fusion transcripts revealed by our mRT-PCR assay. The concordance rate between mRT-PCR and cytogenetics was 91.7%. However, false negative results were found in three cases who have inv(16), t(4;11) or t(11;19)(q23;p13.1), respectively. Seven cryptic translocations including ETV6-RUNX1, MLL-MLLT3, MLL-MLLT4, and PML-RARA were detected. This mRT-PCR assay is a useful screening tool in acute leukemia because it provides rapid and reliable detection of clinically important chimeric transcripts. In addition, cryptic translocations provide additional genetic information that could be clinically useful.
Acute Leukemia; Multiplex RT-PCR; Cytogenetics; Cryptic Translocations
It is critical to differentiate heparin-induced thrombocytopenia (HIT) from disseminated intravascular coagulation (DIC) in heparinized intensive care unit (ICU) patients with thrombocytopenia because the therapeutic approach differs based on the cause. We investigated the usefulness of PF4/heparin antibody tests in these patients.
A total of 127 heparinized ICU patients whose platelet counts were <150×109/L or reduced by >50% after 5-10 days of heparin therapy were enrolled. PF4/heparin antibodies were measured using 2 immunoassays. We assessed the probability of HIT by using Warkentin's 4T's scoring system for antibody positive patients and compared routinely performed coagulation test results between patients with and without antibodies to evaluate the ability of these tests to discriminate between HIT and DIC.
Positive results were obtained for 14 (11.0%) and 11 (8.7%) patients in the 2 assays. The analysis performed using the 4T's scoring system revealed that 11 of 20 (15.7%) patients with antibodies in at least 1 assay had intermediate or greater probability of HIT. Patients without antibodies had significantly higher levels of D-dimer than those with antibodies. However, there were no intergroup differences in platelet counts, PT, aPTT, fibrinogen, DIC score, and rate of overt DIC.
Seropositivity for PF4/heparin antibody was 8.7-11.0% in the patients with thrombocytopenia, and more than a half of them had an increased probability of HIT. Among the routine coagulation tests, only D-dimer was informative for differentiating HIT from DIC. PF4/heparin antibody test is useful to ensure appropriate treatment for thrombocytopenic heparinized ICU patients.
Intensive care units; Platelet factor 4; Heparin; Antibody; Heparin-induced thrombocytopenia