Search

Objective: To analyze the genetic landscape of multiple fusion genes in patients with de novo acute myeloid leukemia (AML) and investigate the characteristics of immunophenotypes and mutations. Methods: The results of multiple fusion genes from 4192 patients with de novo AML were retrospectively analyzed from 2016 to 2020. In addition, the immunophenotypical data and the mutational results from high-through put method were statistically investigated and correlated as well. Results: ①Among the 52 targets, 29 different types of fusion genes were detected in 1948 patients (46.47%) with AML, which demonstrated an "exponential distribution" . ② As the age increased, the number of patients with fusion gene increased first and then decreased gradually. The total incidence rate of fusion genes and MLL rearrangment in children were significantly higher than those in adults (69.18% vs 44.76%, 15.35% vs 8.36%) . ③The mutations involving FLT3 and RAS signaling pathway contributed most in patients with MLL rearrangment. ④No specific immunophenotypic characteristics were found in AML patients with MLL or NUP98 rearrangements. Conclusion: Nearly half of AML patients were accompanied by specific fusion gene expression, the proportions of different fusion genes in pediatric and adults patients were different by multiple PCR. The gene mutations and immunophenotype of these AML patients have certain rules.

Objective: To analyze the clinical manifestations and laboratory features in patients with myeloid neoplasms complicated with clonal T large granular lymphocyte (T-LGL) proliferation. Methods: The clinical data of 5 patients with myeloid neoplasms complicated with clonal T-LGL proliferation from November 2017 to November 2018 in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College were analyzed retrospectively. Results: The median age was 60 years old. All patients had a history of abnormal peripheral blood cell counts for over 6 months. The absolute lymphocyte count in peripheral blood was less than 1.0×10(9)/L. In addition to the typical T-LGL phenotype, the immunophenotype was heterogenous including CD4(+)CD8(-) in 2 patients, the other 3 CD4(-)CD8(+). Four patients were αβ type T cells, the other one was γδ type. STAT3 mutation was detected in 1 patient by next-generation sequencing, the other 4 cases were negative. Conclusions: Clonal T-LGL proliferation with myeloid neoplasm develops in an indolent manner, mainly in elderly patients. Hemocytopenia is the most common manifestation. The diagnosis of T-LGL proliferation does not have specific criteria, that it should be differentiated from other T cell proliferative disorders, such as T-cell clones of undetermined significance. STAT3 or STAT5b mutation may help distinguish.

Objective: To analyze the prognostic factors of transfusion-dependent non-severe aplastic anemia (TD-NSAA) patients treated with cyclosporine A (CsA) and androgen. Methods: Clinical data of 77 consecutive TD-NSAA patients treated with CsA and androgen were retrospectively analyzed between 2010 and 2013. We obtained clinical manifestations and baseline parameters of routine blood test from responders, and compared those with non-responders. All data were analyzed by univariate analysis and multivariate analysis. Results: In 77 patients, there were 43 (55.8%) patients achieved hematological response after 6 months'treatment, and 53 (68.8%) patients got response after 12 months. Univariate analysis showed that platelets baseline was the only factor related to hematological response [19 (6-61) ×10(9)/L vs 13.5 (5-45) ×10(9)/L, P =0.001] after 6 months therapy. After 12 months, the statistical differences were maintained, which were platelets baseline [18 (6-61) ×10(9)/L vs 10.5 (5-45) ×10(9)/L, P <0.001], absolute reticulocytes [0.03 (0.01-0.06) ×10(12)/L vs 0.029 (0.02-0.06) ×10(12)/L, P =0.043], transfusion-dependent of platelet ( P =0.007) , transfusion-dependent of platelet and erythrocyte ( P =0.012) . Multivariate analysis showed that platelets baseline could be an independent prognostic factor of hematological response ( P =0.010 or 0.009) . Cutoff value of platelets by receiver operating characteristic curve was 15.5×10(9)/L. Conclusion: Baseline of higher platelets, higher reticulocyte, and no transfusion dependence of platelet are favorable prognostic factors. When platelets baseline is higher than 15.5×10(9)/L, CsA and androgen regimen is rational.

Objective: To investigate the application values of immunophenotypic analysis and molecular genetics in the diagnosis of acute promyelocytic leukemia (APL) . Methods: The retrospective analyses of flow cytometric (FCM) immunophenotypic anyalysis, chromosome karyotype and chromosome fluorescence in situ hybridization (FISH) of 798 outpatient or hospitalization APL patients referred to our hospital between May 2012 and December 2017 were performed to further study the application values of FCM and molecular genetics in the diagnosis of APL. Results: The sensitivity and specificity of FCM were 91.9% and 98.7% respectively. The typical characteristic immunophenotype for APL was as of follows: a high SSC, absence of expression of cluster differntiation (CD) CD34 and HLA-DR, and expression or stronger expression of CD33, consistent expression of CD13, CD9, CD123, expression of CD56, CD7, CD2 (sometimes) . The rest 10% of the cases harbored atypical APL phenotypes, generally accompanied by CD34 and/or HLA-DR expression, decreased SSC and often accompanied by CD2 expression, it was difficult to definitively diagnose APL by this FCM phenotype, and their diagnoses depended on the results of genetics or molecular biology tests. Compared with normal individuals, complex karyotypes APL with t (15;17) translocation, other variant translocations and variant t (11;17) , t (5;17) had no significant differences in terms of their FCM phenotypes. Conclusions: FCM could rapidly and effectively diagnose APL. Despite the fact that complex karyotypes with various additional chromosomal abnormalities were detected in approximately one third of APL cases in addition to the pathognomonic t (15;17) (q22;q21) , they had no observable impact on the overall immunophenotype. Molecular and genetic criteria were the golden criteria for the diagnosis of APL. About 10% of immunophenotyping cases relied on molecular genetics for diagnosis.

Objective: Analysis of the molecular characteristics of eosinophilia. Methods: Targeting sequence to 24 patients with chronic eosinophilic leukemia (CEL) with rearrangement of PDGFRA, PDGFRB, or FGFR1 and 62 patients with hyper-eosinophilic syndrome (HES). Mutation annotation and analysis of amino acid mutation using authoritative databases to speculate on possible pathogenic mutation. Results: Thirty-seven kinds of clonal variant were detected from 17 patients with CEL, no recurrent mutation site and hot spot region were found. No pathogenic mutation was detected in 19 patients with PDGFRA rearrangement, but pathogenic mutations of ASXL1, RUNX1 and NRAS were detected from 2 patients with FGFR1 rearrangement who progressed to acute myeloid leukemia and 1 patient with PDGFRB rearrangement who progressed to T lymphoblastic lymphoma, respectively. One hundred and two kinds of clonal abnormalities were detected in 49 patients with HES. The main hot spot mutation regions included: CEBPA Exon1, TET2 Exon3, ASXL1 Exon12, IDH1 Y208C, and FGFR3 L164V. CRRLF2 P224L and PDGFRB R370C point mutations were detected separately in 2 patients with HES who treated with imatinib monotherapy and achieved hematologic remission. Conclusion: The pathogenesis of CEL with PDGFRA, PDGFRB or FGFR1 rearrangement is usually single, and the progression of the disease may involve other driver mutation. A variety of genes with hot mutation regions may be involved in the pathogenesis of HES, and some mutation sites are sensitive to tyrosine kinase inhibitors.

Objective: To investigate the spectrum of gene mutations in adult patients with B-acute lymphoblastic leukemia (B-ALL), and to analyze the influences of different gene mutations on prognosis. Methods: DNA samples from 113 adult B-ALL patients who administered from June 2009 to September 2015 were collected. Target-specific next generation sequencing (NGS) approach was used to analyze the mutations of 112 genes (focused on the specific mutational hotspots) and all putative mutations were compared against multiple databases to calculate the frequency spectrum. The impact of gene mutation on the patients' overall survival (OS) and recurrence free survival (RFS) was analyzed by the putative mutations through Kaplan-Meier, and Cox regression methods. Results: Of the 113 patients, 103 (92.0%) harbored at least one mutation and 29 (25.6%) harbored more than 3 genes mutation. The five most frequently mutated genes in B-ALL are SF1, FAT1, MPL, PTPN11 and NRAS. Gene mutations are different between Ph + B-ALL and Ph - B-ALL patients. Ph - B-ALL patients with JAK-STAT signal pathway related gene mutation, such as JAK1/JAK2 mutation showed a poor prognosis compared to the patients without mutation (OS: P =0.011, 0.001; RFS: P =0.014,<0.001). Patients with PTPN11 mutation showed better survival than those without mutation, but the difference was not statistically significant ( P value > 0.05). Besides, in Ph + B-ALL patients whose epigenetic modifications related signaling pathway genes were affected, they had a worse prognosis (OS: P =0.038; RFS: P =0.047). Conclusion: Gene mutations are common in adult ALL patients, a variety of signaling pathways are involved. The frequency and spectrum are varied in different types of B-ALL. JAK family gene mutation usually indicates poor prognosis. The co-occurrence of somatic mutations in adult B-ALL patients indicate the genetic complex and instability of adult B-ALL patients.

Objective: To investigate the feasibility of multiplex real-time RT-PCR with fluorescent probes in early screening of Ph-like acute lymphoblastic leukemia (ALL) and analyze the clinical feature and prognos. Method: A total of 118 adult B-ALL patients diagnosed between October 2010 and March 2016 were enrolled in this study. Multiplex RT-PCR was used to detect the Ph-like ALL related fusion gene and CRLF2 expression in 58 BCR-ABL and MLL rearrangement negative patients. The clinical features, treatment response and prognosis were analyzed in Ph-like fusion gene positive and/or CRLF2 over-expression patients. Result: Among 58 patients, 9 patients (9/58, 15.5%) showed Ph-like ALL related fusion genes positive and 10 patients (10/58, 17.2%) showed CRLF2 over-expression. There were statistical differences in age, WBC count, immunophenotypes, cytogenetics and risk stratification among Ph-like fusion gene positive or CRLF2 over-expression patients, Ph(+) patients, MLL(+) patients and B-other patients. The 2-year overall survival rates were 65%, 47%, 64% and 74% respectively among these four groups ( P =0.043) . The 2-year relapse free survival rates were 51%, 39%, 62% and 70% respectively among these four groups ( P =0.010) . Conclusion: Routine screening of Ph-like ALL by multiplex RTPCR is feasible.

Objective: To estimate the long-term outcomes and the prognostic factors of homoharringtonine, cytarabine, daunorubicin or idarubicin (HAD/HAI) as induction chemotherapy in de novo acute myeloid leukemia (AML)., Methods: The CR rate, overall survival (OS) rate, relapse free survival (RFS) rate were retrospectively assayed in 143 de novo AML patients who received the HAD/HAI induction chemotherapy. The outcomes were compared among prognostic groups according to world health organization (WHO) classification, genetic prognosis and initial white blood cell (WBC) count. The role of consolidation chemotherapy consisting of middle-dosage Ara-C (MD-Ara-C) on long term survival was evaluated., Results: Of 143 patients, 112 (78.3%) achieved CR after the first course of HAD/HAI induction treatment, and early death occurred in only one case. Notably, the CR rate of patients with an initial WBC count ≥100×10(9)/L was not significantly different from those with an initial WBC count<100× 10(9)/L (70.4% vs 80.2%, P=0.266). The CR rate for the patients with favorable, intermediate and unfavorable integrated genetics risk factors was 93.7%, 71.4% and 61.3%, respectively, the difference between groups was statistically significant (P=0.001). Patients with FLT3-ITD mutation obtained similar CR rate (70.6%) to that of patients with FLT3 wild type (79.3%, P=0.528).The estimated 5-year OS rate and 5-year RFS rate for all patients was 40.0% and 37.0%, respectively, with a median follow-up of 24 (range 1-104) months. The median survival time was 30 [95%CI (12, 48)] months. 5-year OS and 5-year RFS of the 96 patients who achieved CR after first course chemotherapy without undergoing allo-HSCT in complete remission was 47.0% and 38.0%, respectively. 5-year OS was significantly higher in MD-Ara-C consolidation group than in no MD-Ara-C consolidation group among CR patients without allo-HSCT (58.0%, 19.0%, respectively, P=0.004). In patients who obtained CR after first course and received MD-Ara-C consolidation without allo-HSCT, the 5-year OS of patients with hyperleukocytosis was not significantly lower than that of patients without hyperleukocytosis (55.5%, 58.8%, respectively,P=0.419). FLT3-ITD mutation patients showed similar 5-year OS to that of wild type FLT3 patients (51.4%, 60.2%, respectively, P=0.482). And furthermore, 5-year OS of favorable, intermediate and unfavorable integrated genetics groups were 59.1%, 62.5%, 51.9%, respectively (P=0.332) in this subgroup., Conclusion: HAD/HAI induction chemotherapy with sequential consolidation of MD-Ara-C could obtain satisfactory CR rate and long-term survival rate in de novo AML, especially for patients with hyperleukocytosis or FLT3-ITD mutation. It yet remains to be verified by large sample, prospective studies.

Objective: To explore the application of BIOMED- 2 standardized immunoglobulin (Ig) gene rearrangement system in the diagnosis of multiple myeloma (MM), and the significance of clonality analysis by multiplex-PCR amplifications., Methods: A total of 167 cases of MM bone marrow samples from 2009 to 2013, and 20 cases of reactive plasmacytosis used as the controls were included in this study. Multiplex-PCR amplifications were performed and the Ig gene rearrangements were analyzed using BIOMED-2 standardized clonality analysis system., Results: ① Of 167 MM cases, 107 showed IgH VH-JH rearrangement, 33 showed IgH DH-JH rearrangement, and 30% showed IgH DH-JH rearrangement in 60 IgH VH-JH rearrangement negative MM cases. The difference was statistically significant between IgH VH-JH rearrangement positive and negative cases (14.0% vs 30.0%, P=0.032). The total positive rate of IgH VH-JH, IgH DH-JH and IgK was 94.6%. The 20 reactive plasmacytosis (RP) cases showed negative Ig gene rearrangement. 2 of 167 MM cases, 9 (5.4%) showed clonal IgH rearrangement by agarose electrophoresis were confirmed as polyclonality by capillary electrophoresis. ③ Of 53 MM cases who have been detected by Ig gene rearrangement system and fluorescence in situ hybridization (FISH) for IgH simultaneously, 36 showed IgH rearrangement, 26 showed FISH IgH positive, and the difference was statistically significant (67.9% vs 49.1%, P=0.049)., Conclusion: Combined detection of IgH VH- JH, IgH DH- JH and IgK could improve the positive rate of MM clonality dramatically, and measurement of IgH DH-JH rearrangement was more important in the IgH VH- JH negative cases. Ig gene rearrangement system was a faster and more sensitive method than FISH IgH. Application of BIOMED- 2 standardized immunoglobulin (Ig) gene rearrangement system is of significance for MM diagnosis.

Objective: To investigate the myeloperoxidase (cMPO) expression pattern by flow cytometry (FCM) in patients with acute myeloid leukemia (AML) and its role in classifying AML., Methods: Eight- color multiparametric FCM with CD45/SSC gating was used to determine the cMPO expression in 502 AML patients., Results: The positive rate of cMPO in all patients was 58.0%, in which the proportion of normal positivity, dim positivity and partial positivity was 21.5%, 34.1% and 2.4%, respectively. The remaining case (42.0%) were all negative. In AML with t (15;17）(q22;q12)/PMLRARα, the positive rate was the highest (100%) and the intensity was similar to that of the normal granular leukocytes, followed by AML with t (8;21（q22;q22/RUNX1-RUNX1T1, the positive rate was 91.4% and the intensity was mostly dim. AML with minimal differentiation and acute megakaryoblastic leukemia were all cMPO negative. The positive rates of cMPO in the remaining subtypes were between 22.7% and 76.2%., Conclusion: The positive rate and intensity of cMPO were significantly different among different subtypes of AML.

Objective: To study the clinical and pathologic features of multiple myeloma(MM) with CCND1., Methods: Retrospectively analyzed the clinical and pathologic profiles of 158 patients with MM from 2010 to 2013. The clinical and morphologic features of bone marrow aspiration, biopsy and immunophenotypic analysis which was carried out by flow cytometry and immunohistochemistry were analyzed in all patients with MM respectively. CCND1 translocation was studied by FISH method in all cases. Classical cytogenetic studies of bone marrow were performed in 24 cases whose CCND1 was positive., Results: In the 158 patients with MM, CCND1 was detected in 31 patients (19.6%）. In 31 patients, type IgA, IgD, IgG, IgM, light-chain only and nonsecretory MM were 4 cases,4 cases,11 cases,1 case, 6 cases and 5 cases respectively. A high incidence of CCND1 was observed in IgD and nonsecretory MM comparied with IgA and IgG respectively (P<0.05). but no statistical significance was reached between κ and λ type patients (P=0.627). The morphology of plasma cell in bone marrow biopsies were small Lymphocyte- Like 24 cases,mature plasma cell 6 cases and immature plasma cell 1 case. Immunophenotype of all 31 cases was CD38⁺CD138⁺CD19⁻CD45⁻, (CD56⁺ in 11 cases, CD20⁺ in 9 cases, CD117⁺ in 3 cases. MM with CCND1 showed a strong association with CD20 expression, the lack of CD56 expression. Immunohistochemistry showed positive for cyclinD1 in 22 cases., Conclusion: A high incidence of CCND1 was detected in the IgD and nonsecretory MM, and correlated with Small Lymphocyte- Like, higher positive rate of CD20, cyclinD1 and the lack of CD56 expression. MM with CCND1 must be distinguished from LPL and other mature B cell lymphomas which have plasmacytoid differentiation.

Objective: To investigate the sensitivity and specificity of eosin-5'-maleimide (EMA)assay for the diagnosis of hereditary spherocytosis (HS), and to verify the stability of reagent and samples., Methods: EMA flow cytometry test, NaCl-osmotic fragility test and acidified glycerol lysis test were performed using peripheral blood samples from 80 patients with HS and 44 patients with other blood diseases, the sensitivity and specificity of the three methods were compared, and the feasibility of EMA binding test was estimated. The stability of EMA reagent and HS samples stored at different temperatures were tested., Results: Among the 124 tested samples, the sensitivity and specificity of EMA binding test was 0.925 and 0.954, that of NaCl-osmotic fragility test was 0.950 and 0.455, and that of acidified glycerol lysis test was 1.000 and 0.318, respectively. Although the sensitivity of NaCl-osmotic fragility test and acidified glycerol lysis test was a little higher than that of EMA binding test, the specificity of the former two methods was poor, they couldn't clearly distinguish whether spherocytosis is hereditary spherocytosis. The experiment results showed that EMA was sensitive to the temperature and should not be stored in a small aliquots at -80 ℃ over a period of 6 months. The stability of the HS sample was better, 6 days storage at 4 ℃ and 3 days storage at room temperature had no influence on the results., Conclusion: EMA binding test by flow cytometry showed good sensitivity and specificity for HS diagnosis. EMA reagent should be stored at-80 ℃ and the HS samples should be tested within 6 days storage at 4 ℃ and 3 days at room temperature.

Objective: To investigate the outcomes of autologous stem cell transplantation (ASCT) for patients with aggressive peripheral T-cell lymphoma (PTCLs) in advanced stage., Methods: The clinical data of 25 patients in complete remission (CR) with aggressive PTCLs received ASCT from May 1997 to June 2013 were retrospectively analyzed., Results: ① Of the 25 cases, 16 were unspecified PTCL (PTCL-U), 4 with angioimmunoblastic T cell lymphoma (AITL), 3 with anaplastic large cell lymphoma (ALCL) and 2 with hepatosplenic T cell lymphoma (HSTL), with a median age of 30(12-54) years old. Ratio of male to female is 16∶9. The distribution of stages was 8 cases with stage Ⅲ and 17 patients with stage Ⅳ. Nine patients presented with bone marrow involvement. Before ASCT, 18 patients were in CR1 and 7 patients were in CR2. ②Two patients with HSTL in stage ⅣB and IPI score 4/5 in CR1 relapsed and died within 12 months after ASCT. At a median follow-up of 38 (range 14-110) months, the estimated 3-year probability of PFS and OS for the other 23 patients was (63.1 ± 10.5)% and (71.8 ± 9.9)%, respectively. The patients in first CR had a better survival than the patients in second CR. The 3-year probability of PFS were (74.9 ± 11.0)% vs (33.3 ± 19.2)% (P=0.092) and OS were (80.2 ± 10.4)% vs (50.0 ± 20.4)% (P=0.043), respectively. The 3-year probability of PFS and OS were (40.0 ± 17.4)% and (53.3 ± 17.3)% in bone marrow involvement patients and the corresponding figure were (77.9 ± 11.3)% and (84.4 ± 10.2)% in non- bone marrow involvement patients., Conclusion: ASCT could improve the survival of aggressive PTCLs. Non CR1 status and bone marrow involvement had negative influence on OS in patients with aggressive PTCLs treated by ASCT. The prognosis was very poor in patients with HSTL and satisfactory regimens should be investigated.

Objective: To observe the clinical and biological characteristics of Non-IgM-secreting lymphoplasmacytic lymphoma (LPL) and draw the differences between non-IgM LPL and Waldenström macroglobulinemia (WM)., Methods: Records of 13 patients with non-IgM LPL were retrospectively analyzed between January 2000 and December 2013. The cytogenetic aberrations were detected by fluorescence in situ hybridisation (FISH)., Results: In the cohort, 7 males and 6 females with a median age of 63 years (range 43 to 74), two patients were IgA secreting, 6 with IgG secreting and 5 patients without monoclonal globulin. The major complaint at diagnosis included anemia associated symptom (53.8%), mucocutaneous hemorrhage and superficial lymphadenopathy (15.4%). Eight patients had B symptom at diagnosis. All of the 13 patients had bone marrow involvement and anemia, and 10 patients had 2 or 3 lineage cytopenia. In 5 patients with available immunophenotypic data, all expressed CD19, CD20, CD22 and CD25, but missed the expression of CD10, CD103 and CD38. Two cases had CD5 or sIgM positive alone. Another 2 patients were CD23 or CD11c positive and 3 patients were FMC7 positive. Cytogenetic aberrations had been detected by FISH in 7 patients, but only two (28.6%) patients had aberrations with del(6q)., Conclusion: The clinical and biological characteristics had no significantly difference between non-IgM LPL and WM.

Objective: To report the diagnosis, differential diagnosis and treatment of three rare cases of primary bone marrow diffuse large B cell lymphoma (DLBCL), and to improve the recognition of this disease., Methods: The clinical characteristics, therapeutic course and the outcome of these patients were reviewed. Meanwhile, a series of examinations including morphology, flow cytometry, immunohistochemistry and molecular biology of bone marrow samples were also performed., Results: These three patients who were old at the onset age (56, 60 and 70 years old), primarily revealed as abnormal blood count and experienced an aggressive course of disease. Physical and imaging examination showed no enlargement of lymph node, liver and spleen, the patients were finally diagnosed as primary bone marrow DLBCL by bone marrow morphology, flow cytometry and immunohistochemistry analyses. They were treated with rituximab combined chemotherapy, which achieved a complete response, but still need longer follow-up to further evaluate their survival., Conclusion: Primary bone marrow DLBCL was encountered rarely in clinical practice, and this is the first report in China. Further investigation of pathogenesis and therapeutic strategies of this rare disease was warranted.

Objective: To explore the feasibility of detecting lymphoma with the application of BIOMED-2 standardized immunoglobulin/T cell receptor (IG/TCR) gene rearrangement system in formalin fixed paraffin-embedded (FFPE) tissue samples, and to discuss the relationship between the longest amplification fragment of extracted DNA and positive detection rate of different IGH V-J primers., Methods: DNA was extracted from 50 cases of FFPE tissue samples. Multiplex-PCR amplifications were performed and then the IG/TCR gene rearrangements were analyzed using BIOMED-2 standardized clonality analysis system., Results: (1)When the DNA concentration was diluted to 50-100 ng/μl from 100-500 ng/μl, the proportion of the longest amplification fragment (300-400 bp) of DNA was improved from 10.0% to 90.0% in 30 cases of diffuse large B cell lymphoma (DLBCL) wax roll samples (P<0.01). The positive rate of IGH+IGK was increased from 46.7% to 83.3%, the difference was statistically significant (P=0.006). The lengths of the longest amplification fragments of DNA were all longer than 300 bp in the paraffin section samples of DLBCL. The positive rate of IGH+IGK of these samples was 96.7%. The difference of the positive rate of IGH+IGK between the wax roll samples and the paraffin section samples had no statistical significance (P=0.195). (2)When the concentration of DNA was high, most of the longest amplification fragments of extracted DNA were 100 bp or 200 bp, and the detection rate of short fragment IGH FR3 was more stable than that of long fragment IGH FR1. (3)The clonality analysis of TCRG+TCRB in all 13 cases of peripheral T cell lymphoma samples showed positive results, while no positive IG/TCR clones were found in 7 cases of reactive lymphoid tissue hyperplasia in control group., Conclusion: Dilution of DNA is the only method to improve not only the proportion of longest fragment amplification but also the detection rate of clonality. The detection rate of IGH FR3 would not be affected by the concentration of DNA. The application of BIOMED-2 standardized IG/TCR gene rearrangement system in FFPE tissue samples plays an important role in the lymphoma diagnosis.

Objective: To evaluate the three-probe fluorescence in situ hybridization (FISH) panel in the diagnosis of pediatric B cell acute lymphoblastic leukemia (B-ALL)., Methods: Three-probe (TELAML1, BCR-ABL and MLL) FISH and conventional cytogenetic analysis were performed in 207 children with B-ALL., Results: In 207 B-ALL children, the three-probe FISH panel assay showed that 151 cases carried genetic aberrancies with a positive rate of 72.9%, including 44 cases with typical positive signal patterns and 148 cases with atypical signal patterns (among them 41 cases have multiprobe abberancy). The conventional cytogenetic analysis detected 53 cases chromosomal abnormality with a positive rate of 25.6%., Conclusion: The detection rate of genetic abnormalities in newly- diagnosed pediatric B-ALL could be significantly improved by using three-probe FISH panel upon conventional cytogenetic analysis.

Objective: To investigate the incidence, molecular features and clinical significance of CCAAT/enhancer binding protein alpha (CEBPA) gene mutation in patients with acute myeloid leukemia (AML)., Methods: Mutation analysis of the entire coding region of CEBPA gene in 206 de novo AML patients was performed by using polymerase chain reaction (PCR) followed by sequence analysis and fragment length analysis., Results: Of 206 AML patients, 31 (15%) had CEBPA gene mutations, including 23 with double mutations (duCEBPA) and 8 with single mutation (siCEBPA). CEBPA gene mutations presented mainly in M2 subtype or intermediate risk patients. As compared with those with wild type CEBPA gene, patients with mutated CEBPA gene were of higher white blood cell counts [20.92(0.86-351.43)× 10(9)//L vs 8.17(0.47-295.2) × 10(9)/L, P=0.003], higher hemoglobin levels [97.5(51-128) g/L vs 80.5(13-153) g/L, P=0.015] and lower platelet counts [27.5(5-81)× 10(9)//L vs 44(3-548)× 10(9)/L, P=0.004]. Patients with CEBPA gene mutation had higher complete remission (CR) rate than those with wild type (P=0.009). While co-existing of NPM1 and siCEBPA mutations was observed in M5 subtype (2/8, 25%), NPM1 gene mutation was not present in any patients with duCEBPA mutation (0/23, 0%). Dynamic tracking analysis showed that CEBPA mutations disappeared at CR, and the same mutations re-appeared at relapse. When compared to sequence analysis, the coincidence rate of CEBPA mutations detected by fragment length analysis was 100% (54/54)., Conclusion: CEBPA gene mutation is a recurring genetic change in AML patients and has a certain correlation with clinical and laboratory features. It could be reliably used as a potential marker for minimal residual disease follow up. The prognostic significance of co-existing of siCEBPA with NPM1 mutations in patients with AML-M5 subtype needs further investigation.