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Purpose To explore the diagnostic value of dif-ferent fluorescence in situ hybridization(FISH)signal types and chromosomal karyotyping analysis in ETV6/RUNX1-positive B-cell acute lymphoblastic leukemia(B-ALL).Methods Clini-cal data of 164 newly diagnosed ETV6/RUNX1-positive B-ALL patients were collected for retrospective analysis of chromosomal karyotyping and FISH.Results Among the 164 patients,163 positive cases were detected by FISH,among them the classic 2F1R1G signal type was found in 61 cases,and 102 cases showed non-classic signal types,with 2F1G and 1F1R2G signal types being the most common,indicating ETV6 deletion.Among them,the classic 2F1R1G signal type was found in 61 cases,and 102 cases showed non-classic signal types,with 2F1G and 1F1R2G signal types being the most common,indicating ETV6 deletion.Among the 125 children who could undergo karyoty-ping analysis,106 had a normal karyotype and 19 had an abnor-mal karyotype,with no detection of t(12;21)translocation.Conclusion FISH technology has high sensitivity in detecting ETV6/RUNX1 fusion genes,and it often manifests as non-clas-sic signal types,including ETV6 deletions.Chromosomal karyo-typing analysis helps to identify complex karyotypes and polyploidy but is not conducive to detecting t(12;21)fusion.Therefore,both FISH signal types and karyotyping analysis play indispensable roles in ETV6/RUNX1-positive B-ALL.
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Background and Objectives: In acute leukemia, all diagnostic criteria and treatment protocols are based on cytogenetic and molecular geneticfindings. Despite recent advances in molecular biology, cytogenetic studies still play a pivotal role in the sub-classification of B-lymphoblastic leukemia (B-ALL). B-ALL is characterized by clonal cytogenetic abnormalities with numerical chromosomal aberrations being more common. An extra copy of chromosome 5 is common to see in cases with hyper diploidy. However, a gain of chromosome 5 as a sole anomaly is exceptionally rare in B-ALL. To date, trisomy 5 as a sole abnormality is reported in few cases only. We aimed to report the clinicopathologic profile of this rare finding to increase knowledge and highlight the disease course of these patients.Methods: We report a case of a 14-year boy presented with fever, lethargy and episodes of nasal bleeding for two weeks. He was admitted to the pediatric oncology unit at Indus hospital and health network, Karachi. Flowcytometry performed on peripheral blood using 8-color flowcytometry. Conventional karyotyping was performed by GTG banding. FISH panel was comprisedof dual color dual fusion probes for BCR::ABL1and ETV6::RUNX1whereas break apart probe for KMT2A (Metasystem, Germany).Digital image analysis for karyotyping and FISH was done on Leica Biosystems, Cytovision MB8.Results:Flowcytometry results were consistent with B-ALL. Cytogenetic analysis on his bone marrow aspirate revealed trisomy 5 as a sole abnormality with no evidence of any other clonal cytogenetic abnormality. FISH studies for BCR::ABL1, ETV6::RUNX1and KMT2Ashowed no evidence of gene rearrangements.Conclusion:Trisomy 5 is a very rare cytogenetic aberration. Only few cases reported in children. Inferior outcome is reported in both children and adults. The increasing number of reported cases raises the possibility of a distinct cytogenetic entity. Its prognostic and therapeutic implications are yet to be explored.
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OBJECTIVE@#To discover the relationship between matrix remodeling associated 7 (MXRA7) and acute B lymphoblastic leukemia (B-ALL), and explore the effect of MXRA7 on the biological functions of B-ALL cell line REH.@*METHODS@#The expression of MXRA7 in blood diseases was searched and analyzed through BloodSpot database. Real-time qPCR was used to detect the expression level of MXRA7 in B-ALL cell line 697 and REH cells. Lentivirus-mediated shRNA interference technology was utilized to knock down the expression of MXRA7 in REH cells. The effects of MXRA7 on the biological functions of REH cells were studied by in vitro experiments. Cell proliferation was detected by CCK-8 assay, cell cycle was detected by PI staining, cell apoptosis was detected by Annexin V and 7-AAD staining, and the expression of apoptosis pathway related proteins was detected by Western blot.@*RESULTS@#Database analysis showed that MXRA7 was highly expressed in B-ALL patients, and real-time qPCR results showed that MXRA7 was also highly expressed in cell lines 697 and REH cells. Knockdown of MXRA7 in REH cells inhibited the cell proliferation and increased the percentage of G0/G1 phase cells. After treatment with cytarabine, the apoptotic ratio was increased in MXRA7-impaired REH cells, and the activation of caspase-3 and caspase-9 were also increased.@*CONCLUSION@#Knockdown of MXRA7 can reduce the malignancy of REH cells by inhibiting the cell proliferation and increasing the sensitivity of REH cells to cytarabine. These results indicate MXRA7 may be as a novel target for the treatment of B-ALL, and the potential usefulness of MXRA7 in B-ALL deserves further investigation.
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Humans , Apoptosis , Cell Line, Tumor , Cell Proliferation , Cytarabine , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolismABSTRACT
The IKAROS family zinc finger 1 (IKZF1) gene encodes the Ikaros protein, which regulates the development and differentiation of hematopoietic cells, and is essential for autoimmune and tumor suppression.With the development of genomics, IKZF1 has become an important prognostic biomarker for the occurrence and progression of acute lymphoblastic leukemia.Mutations in the IKZF1 gene appears in about 15% of childhood acute B-lymphoblastic leukemia.The mutation impairs the tumor-suppressor function of the IKZF1 gene, enhances the proliferation and anti-apoptotic ability of leukemia cells, and develops resistance to key chemotherapy drugs.IKZF1 mutations are more common in patients with other adverse prognostic factors and face difficulties in the course of treament with high recurrence rate, short remission period and high mortality.Intensive therapy, hematopoietic stem cell transplantation and immunotherapy for childhood acute B-lymphoblastic leukemia with IKZF1 mutation can reduce the recurrence rate and improve the remission rate and survival rate.Targeted therapy is promising to improve the prognosis of children with IKZF1 mutation.
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Objective:To explore the predictive value of peripheral blood cytokine models on organ functional impairment after chimeric antigen receptor T(CAR-T) cell therapy in children with B-lineage lymphocytic leukemia.Methods:The clinical data of 44 children with acute B-lineage lymphoblastic leukemia who received CAR-T cell therapy at Children′s Hospital of Soochow University from September 2018 to October 2020 were retrospectively analyzed.Peripheral blood cytokines, including interleukin(IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor-α, interferon(IFN)-γ and IL-17A, were measured daily for 14 days after receiving CAR-T cell therapy.The trend of peripheral blood cytokine levels was analyzed at the endpoint of organ function recovery or death within 14 days after CAR-T cell treatment.Receiver operating characteristic curve was used to establish a mathematical prediction model to predict the occurrence of organ damage in the children.Results:Of the 44 children, 31 cases were boys and 13 cases were girls, with a median age of 7.96 (5.19, 11.48)years.Cytokine release syndrome(CRS) response occurred in 95.5% (42/44) children, with 88.1% (37/42) had a grade 1-3 CRS response, and 16.7% (7/42) had a severe grade 4-5 CRS response.Using IL-6>3 892.95 pg/mL as cut-off value, the area under the curve(AUC) for predicting acute respiratory failure was 0.818, with a sensitivity of 0.8 and a specificity of 0.735, while combining IFN-γ>414.4 pg/mL, IL-6>3 892.95 pg/mL and IL-2>27.05 pg/mL were the three cut-off values, with an AUC of 0.741, sensitivity of 0.6 and specificity of 0.912 for predicting acute respiratory failure. Using IFN-γ>1 699.5 pg/mL as cut-off value, the AUC for predicting shock was 0.908, with a sensitivity of 0.722 and a specificity of 1.With IL-6>4 607.3 pg/mL as cut-off value, the AUC for predicting liver injury was 0.964, with a sensitivity of 1 and a specificity of 0.906, while combining both IL-6>4 607.3 pg/mL and IFN-γ>1 446.2 pg/mL as cut-off values, the AUC for predicting liver injury was 0.977, with a sensitivity of 1 and a specificity of 0.906.Combining both IL-6>6 972.2 pg/mL and IFN-γ>3 981.5 pg/mL predicted a positive predictive value of 62.5% and a negative predictive value of 94.4% for grade 4-5 CRS response, with an AUC of 0.846, a predictive sensitivity of 0.714 and a specificity of 0.838, and all children had a combination of two or more organ function injuries.Conclusion:The combination of IL-6 and IFN-γ can effectively predict the incidence of liver injury and cytokine release syndrome.The combination of peripheral blood cytokines IFN-γ, IL-6 and IL-2 can be used to predict the incidence of acute respiratory failure after the treatment of CAR-T cells in children with acute B-lineage lymphoblastic leukaemia.IFN-γ single index can be used to predict the incidence of shock.The combination of IL-6 and IFN-γ can be used to predict the incidence of liver injury and the severity of CRS.
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Objetivo: Estimar a custo-efetividade do blinatumomabe como novo padrão no tratamento de consolidação de pacientes pediátricos com leucemia linfoblástica aguda de células precursoras B (LLA-B) em primeira recidiva de alto risco. Métodos: Um modelo de sobrevida particionado com horizonte lifetime e ciclo de quatro semanas foi construído na perspectiva do Sistema Único de Saúde (SUS). Sobrevida livre de eventos e sobrevida global foram extrapoladas com base no ensaio clínico 20120215, usando funções paramétricas. A taxa de desconto foi de 5%. O impacto de variações em pressupostos foi explorado em análises de cenário. Resultados: O custo lifetime com desconto para o caso base foi de R$ 351.615 para blinatumomabe contra R$ 97.770 para HC3 (grupo controle de quimioterapia-padrão), com ganho de 9,96 e 6,74 anos de vida ajustados para qualidade (QALYs), respectivamente. A razão de custo-efetividade incremental (RCEI) foi de R$ 78.873/QALY. Considerando um cenário sem descontos, a RCEI foi de R$ 33.731/QALY ganho. Os outros cenários com maior impacto na RCEI foram a exclusão do desperdício de blinatumomabe (isto é, considerando que a sobra em frasco-ampola de um paciente seria reaproveitada para outro paciente: R$ 35.751) e a alteração do tempo de infusão (troca de bolsa em 48 ou 96 horas em vez de 24 horas: R$ 35.515). A probabilidade de o blinatumomabe ser custo-efetivo foi de 65,7% na análise probabilística, considerando um limiar de R$ 95.501. Conclusões: Blinatumomabe é custo-efetivo para pacientes pediátricos com LLA-B derivada em primeira recidiva de alto risco na perspectiva do SUS.
Objective: To estimate the cost-effectiveness of blinatumomab as the new standard treatment of consolidation in high-risk first relapse pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL). Methods: A partitioned survival model with a lifetime horizon and a 4-week cycle was developed from the Brazilian public healthcare payer's perspective (SUS). Event-free survival and overall survival were extrapolated based on data from the 20120215 clinical trial using parametric functions. A 5% discount rate was used, and the impact of variations in model parameters and assumptions were explored in scenario analyses. Results: The discounted base case lifetime cost was R$ 351,615 for blinatumomab vs. R$ 97,770 for standard chemotherapy control group (HC3), with 9.96 QALYs gained with blinatumomab vs. 6.74 QALYs gained with HC3. The incremental costeffectiveness ratio (ICER) was R$ 78,873/QALY. Considering an undiscounted scenario, the ICER was.
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Unified Health System , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Cost-Effectiveness AnalysisABSTRACT
OBJECTIVE@#To establish an animal model of acute B lymphoblastic leukemia (B-ALL) with minimal residual disease.@*METHODS@#The transplanted tumor was formed by subcutaneous injection of 2×107 Nalm-6 cells, and the body weight, activity status and tumor formation status of nude mice were observed. Peripheral blood, bone marrow, liver and spleen and other tissues of nude mice were taken for pathological examination to understand whether the success of subcutaneous modeling was accompanied by systemic metastasis.@*RESULTS@#There were 2×107 Nalm-6 cells injected subcutaneously in nude mice, (11.0±2.5) days later, the tumors of (3-4) × (3-4) mm were observed, the body weight of the nude mice was reduced and activity showed no limited. Infiltration of tumor cells in liver, spleen and bone marrow were observed in pathological sections.@*CONCLUSION@#The animal model of subcutaneous tumor of B-ALL was successfully established in nude mice.
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Animals , Humans , Mice , Body Weight , Disease Models, Animal , Mice, Nude , Neoplasm Transplantation , Neoplasm, Residual , Precursor Cell Lymphoblastic Leukemia-LymphomaABSTRACT
Minimal residual disease (MRD) following B-lymphoblastic leukemia (B-ALL) treatment has gained prognostic importance. Clonal immunoglobulin heavy chain (IGH) gene rearrangement is a useful follow-up marker in B-ALL owing to its high positivity rate. We evaluated the performance and clinical applicability of a next-generation sequencing (NGS) assay for IGH rearrangement in B-ALL MRD monitoring. IGH rearrangement was tested by using fluorescence PCR-fragment analysis and the NGS assay in eight B-ALL patients. The NGS assay was run on two platforms: the Ion Torrent PGM (Thermo Fisher Scientific, USA) (18 samples from 1st to 7th patients) and the MiSeq system (Illumina, USA) (four samples from 8th patient). All initial diagnostic samples and four follow-up samples were positive for clonal IGH rearrangement with fluorescence PCR-fragment analysis and the NGS assay, and six follow-up samples were positive only with NGS. In one case with BCR-ABL1 translocation, BCR-ABL1 quantitative PCR was negative but the NGS IGH assay was positive just prior to full-blown relapse, suggesting the high sensitivity and clinical utility of the NGS assay. The NGS assay is proposed for MRD monitoring in B-ALL Additional studies are needed to confirm the clinical implications of cases showing positive results only in NGS.
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Humans , Fluorescence , Follow-Up Studies , Gene Rearrangement , Immunoglobulin Heavy Chains , Immunoglobulins , Leukemia , Neoplasm, Residual , Polymerase Chain Reaction , RecurrenceABSTRACT
Objective To discriminate morphology and immunophenotype differences between hematogones and lymphoblast to provide some references for the correct identification of hematogones and minimal residual leukemia cells.Methods Immunophenotypes were detected by flow cytometry in a total of 132 bone marrow from 58 patients with acute B lymphoblastic leukemia during diagnosis,remission and relapse.Hematogones were identified based on combination of CD34/CD10/CD19/CD45 or CD34/CD10/CD45/CD19/CD20/CD38.Results Among 132 specimens,45 (34 %) were identified hematogones,the detection range was 0-36 %.Three specimens appeared in diagnosis patients,one in relapse,and the remaining 41 cases in remission.The detection rate of hematogones was 62 % (41/66) in the remission cases.More than 5 % leukemia cells of nucleated cells were detected in diagnosis and relapse,and less than 5 % residual leukemia cells was in 24 specimens from remission patients.In 28 specimens,the co-existence of hematogones and leukemia cells was found,including three in diagnosis,one in relapse and the remaining 24 in remission.Hematogones were characterized in term of variable expression of CD45 and very low side scatter.The early hematogones expressed CD34.With maturation increasing,hematogones gradually lacked CD34.CD19 and CD10 were presented in whole hematogones stage.Early hematogones had expression of CD10.Lymphoblasts showed maturation arrest and more homogeneous populations.SSC values of hematogones were higher than that of normal B cell progenitors.Antigen overexpression or underexpression was not found in normal hematopoietic progenitor B cells,and hematopoietic progenitor B cells did not appear cross-lineage markers,CD20+ cells exhibited continuous distribution from negative to weak positive for normal hematogones.Conclusions Hematogones were present in diagnosis,remission and relapse cases with acute B lymphoblastic leukemia,especially abundant in bone marrow after chemotherapy.It should be careful to diagnose and discriminate the malignant cells from benign cells.By comprehending continuous and complete maturation spectrum of antigen expression for normal hematogones,knowing phenotype of leukemia cells drift change patterns and using multiparameter flow cytometry and optimal antibody combination,it is significant in identifying residual lymphoblasts from hematogones and improving the detection accuracy in minimal residual disease.
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Translocations leading to fusions between the immunoglobulin heavy chain gene (IGH) and various partner genes have been reported in B-cell precursor acute lymphoblastic leukemia (B-ALL). However, submicroscopic deletions within IGH in B-ALL have not been rigorously assessed. In this study, we investigated characteristics of IGH submicroscopic deletions, by FISH, in B-ALL with IGH rearrangements. FISH was performed by using commercially available IGH dual-color break-apart rearrangement probes (Abbott/Vysis, Downers Grove, IL, USA; Kreatech, Amsterdam, Netherlands). The study group included seven B-ALL patients with IGH rearrangements, observed by FISH. Among them, two exhibited deletion of the 5' variable region of IGH by FISH. The B-ALL in these two patients included two kinds of abnormal cells; one had an IGH rearrangement without any IGH submicroscopic deletion, while the other had an IGH submicroscopic deletion, which showed that one normal fusion signal and one 3' IGH signal were detected. Thus, submicroscopic deletion of the IGH 5' variable region may have occurred in either the native or rearranged chromosome 14. These findings indicate that B-ALL with IGH rearrangements may be accompanied by submicroscopic deletions of the IGH 5' variable region, which can be detected by FISH. The clinical significance of such deletions is unclear, but the loss of part of the IGH gene in B-ALL warrants further study.
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Adult , Child , Female , Humans , Infant , Male , Middle Aged , Young Adult , Gene Deletion , Gene Rearrangement , Immunoglobulin Heavy Chains/genetics , In Situ Hybridization, Fluorescence , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/geneticsABSTRACT
Loss of chromosome Y (LOY) in the bone marrow has long been considered as an age-related phenomenon with an incidence of more than 25% in males beyond the age of 80 years. Though reported as an acquired abnormality in myeloid neoplasms, it has rarely been described in B-lymphoblastic leukemia which primarily is a disease of the young. We describe here in three cases of pediatric B-lymphoblastic leukemia with LOY. Conventional cytogenetic studies and fluorescence in situ hybridization studies using centromeric probes for chromosome X and Y on peripheral blood samples ruled out constitutional LOY in all the three cases favoring it to be a neoplastic phenomenon.
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Pneumatosis intestinalis (PI) is a rare condition characterized by multiple pneumocysts in the submucosa or subserosa of the bowel. Here, we report a rare case of asymptomatic PI after chemotherapy induction in an 18-yr-old man with B lymphoblastic leukemia with recurrent genetic abnormalities. The patient was treated conservatively and recovered without complications. The possibility of PI should be considered as a complication during or after chemotherapy for hematologic malignancies. Conservative treatment should be considered unless there are complications, including peritonitis, bowel perforation, and severe sepsis.
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Adolescent , Humans , Hematologic Neoplasms , Peritonitis , Precursor Cell Lymphoblastic Leukemia-Lymphoma , SepsisABSTRACT
Rearrangements of the mixed lineage leukemia (MLL) gene at 11q23 commonly occur in infants with CALLA negative B lymphoblastic leukemia (B-ALL). Most often, these are detected by conventional karyotyping; however, fluorescent in-situ hybridization (FISH) with the help of a dual-color break-apart probe is used to identify cryptic translocations. When there is an MLL gene translocations the usual FISH signal pattern is 1 red-1 yellow fusion signal pattern We present a case of an infant with CALLA negative precursor B-ALL with a characteristic translocations t(4;11) (q21;q23),however,with an unusual MLL FISH signal pattern.
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Humans , In Situ Hybridization, Fluorescence/methods , Infant , Male , Myeloid-Lymphoid Leukemia Protein/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Translocation, GeneticABSTRACT
Acute lymphoblastic leukemia is a cancer of blood cells. It is known as lymphoblastic lymphoma when it involves lymph nodes rather than the blood and bone marrow. The gastrointestinal tract is a predominant site for extra-nodal lymphomas. But, B-lymphoblastic leukemia/lymphoma more frequently presents in the leukemic form than in the lymphomatous form. We herein report a case of B-lymphoblastic leukemia/lymphoma detected as a laterally spreading tumor in the colon. A 54-year-old man was referred to our hospital for removal of multiple colonic polyps. A colonoscopy revealed multiple colonic polyps and several colonic laterally spreading tumors. An esophagogastroduodenoscopy revealed several raised erosive lesions on the fundus and several variable sized sessile polypoid lesions on the duodenum. We diagnosed B-lymphoblastic leukemia/lymphoma following biopsies of the lesions.
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Humans , Middle Aged , Biopsy , Blood Cells , Bone Marrow , Colon , Colonic Polyps , Colonoscopy , Duodenum , Endoscopy, Digestive System , Gastrointestinal Tract , Lymph Nodes , Lymphoma , Precursor Cell Lymphoblastic Leukemia-LymphomaABSTRACT
Loss of heterozygosity (LOH) in chromosome 6p has been reported in a number of tumors and some hematologic malignancies, including ALL. LOH in chromosome 6p, on which the HLA genes are located, can give rise to false homozygosity results in HLA genotyping of patients with hematologic malignancies. Here we report false homozygosity results in HLA genotyping due to the loss of whole chromosome 6 in the neoplastic cells of a patient with ALL. A 33-yr-old Korean female patient was admitted for the evaluation of leukocytosis detected during a workup for headache. Her initial white blood cell count was 336.9x109/L with 84% of blasts in the differential count. Precursor-B lymphoblastic leukemia was diagnosed from a subsequent bone marrow study. HLA high-resolution genotyping of the patient was requested at the time of diagnosis for possible hematopoietic stem cell transplantation. Homozygosity results (A*02:01, B*54:01, C*08:01, DQB1*04:01) were obtained, except for the DRB1 locus (DRB1*04:05, DRB1*11:01), in sequence-based typing. Conventional karyotyping of bone marrow metaphase cells revealed chromosomal abnormalities, with loss of multiple chromosomes including chromosome 6, and reduplication of the remaining chromosomes: 29,X,+X,+8,inv(9)(p11q13),+10,+14,+18,+21[15]/58,idemX2[3]/46,XX,inv(9)[2]. LOH at the HLA region was suspected and HLA genotyping was repeated with the peripheral blood in remission state after induction chemotherapy. All 5 HLA loci were typed as heterozygous (A*02:01, A*02:06, B*40:01, B*54:01, C*03:04, C*08:01, DRB1*04:05, DRB1*11:01, DQB1*03:01, DQB1*04:01). To avoid false HLA typing results in patients with hematologic malignancies, clinicians, as well as laboratory personnel, need to be aware of such problems and take appropriate precautions.
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Adult , Female , Humans , Chromosome Duplication , Chromosomes, Human, Pair 6 , Diagnostic Errors , Genotype , HLA Antigens/genetics , Hematopoietic Stem Cell Transplantation , Karyotyping , Leukocyte Count , Loss of Heterozygosity , Nerve Tissue Proteins/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , RNA-Binding Proteins/geneticsABSTRACT
In B lymphoblastic leukemia/lymphoma (B-ALL/LBL), t(9;22)(q34;q11.2) and t(1;19)(q23;p13.3) are recurrent cytogenetic abnormalities. The concurrent occurrence of both abnormalities is very rare, and only 3 cases have been previously reported. Here, we report a case of adult B-ALL with ider(9)(q10)t(9;22)(q34;q11.2) and der(19)t(1;19)(q23;p13.3). A literature review revealed that ider(9) (q10)t(9;22) is a rare variant of t(9;22) with a deletion of the short arm of chromosome 9. Fifteen cases of ider(9)(q10)t(9;22) have been reported. This abnormality is specific to precursor B-lymphoid neoplasms, such as B-ALL or B-lymphoid blast phase of CML, and is associated with disease progression or short survival. The cytogenetic abnormality t(1;19) is also specific to B-ALL. In most instances of t(1;19), TCF3 is fused to PBX1; however, a few cases have identical translocations but no TCF3-PBX1 fusion, as was observed in our patient. We describe the first case of ider(9)(q10)t(9;22) in combination with TCF3-PBX1 negative t(1;19). The patient underwent imatinib therapy in addition to intensive chemotherapy, but failed to achieve remission.