Adult Acute Lymphoblastic Leukemia Cases Research Articles

EP416: Assessment of the clinical implication of additional cytogenetic abnormalities in acute lymphoblastic leukemia with t(4;11)(q21;q23)

Acute lymphoblastic leukemia (ALL) with KMT2A rearrangement is associated with poor prognosis. The t(4;11)(q21;q23) resulting in KMT2A-AFF1 fusion represents one of the most common translocations involving the KMT2A locus, comprising 2% of pediatric ALL and 5% of adult ALL cases. Pediatric patients, especially infants with t(4;11)(q21;q23), have been reported to have fewer additional cytogenetic abnormalities (ACA) compared with other primary established cytogenetic subgroups. Some studies have thus proposed that the KMT2A-AFF1 fusion may function as a major contributor in driving and maintaining the malignancy.

The Molecular Landscape of KMT2A-Rearranged Leukemia from Infancy to Adulthood Reveals Age and Leukemia-Specific Mutational Patterns

Genetic rearrangements involving the KMT2A gene (KMT2A-R) are seen in around 10% of acute leukemia overall. KMT2A-R occurs in all ages and usually correlates with high-risk clinical features, in particular in infants aged 0-12 months of age with acute lymphoblastic leukemia (ALL). To uncover age- and leukemia-subtype specific molecular patterns in KMT2A-R ALL and acute myeloid leukemia (AML), we performed whole genome (WGS), whole exome (WES), and RNA-sequencing on a well-annotated Nordic KMT2A-R cohort of 104 patients, including infant ALL (n=33), childhood ALL (n=18), adult ALL (n=15), and pediatric AML (n=38) patients. For 77 patients, we performed WGS (40x) at diagnosis and remission as well as WES (140x) on the diagnostic sample, and remaining patients underwent WES only (n=27). RNA-sequencing was performed on 58 cases with available RNA.Twenty-two genes were recurrently altered and remarkably, NRAS, KRAS, FLT3, PAX5, TP53, CDKN2A/B and IKZF1 accounted for 70% of mutations. The landscape of mutations suggested the presence of leukemia and age-specific associations with MYST4, PTPN11, and SETD2 uniquely altered in AML and PIK3CD, DNAH11, NOTCH1, CSMD3 and CDKN2A/B in ALL. Some genes were mutated in both KMT2A-R ALL and AML, but were more common in one disease, such as FLT3 and KRAS in AML and PAX5, TP53 and IKZF1 in ALL. Moreover, age-associated patterns were seen in ALL with NRAS more frequently mutated than KRAS in infant ALL (26% vs 15%), and KRAS more frequently mutated than NRAS in childhood ALL (24% vs 18%), with adult ALL having fewer such mutations (NRAS 13%; KRAS 7%). Alterations of CDKN2A/B and TP53 were absent in infant ALL, detected in childhood and adult ALL only. PAX5 alterations were primarily detected in childhood ALL (22%, 9% infant ALL, 7% adult ALL), with all three PAX5-altered infant cases having the KMT2A-MLLT3 fusion gene. Finally, KMT2A-R pediatric AML had the highest fraction of FLT3 mutations (24%, 9% infant ALL, 11% childhood ALL, 0% adult ALL) and all but one mutation occurred in KMT2A-MLLT3 rearranged cases and most were kinase domain point mutations.We next expanded our analysis to include non-recurrent alterations. PI3K/RAS pathway alterations were detected across ages and subtypes with the highest fraction in pediatric AML (63%) and the lowest in adult ALL (27%, 43% infant ALL, 41% childhood ALL). Further, cell cycle related genes were primarily mutated in childhood (39%) and adult ALL cases (33%) and rarer in infant ALL (12%) and pediatric AML (16%) and genes within the B-cell pathway were more commonly altered in childhood ALL (29%) than in infant ALL (9%). Finally, in line with our previous study (Andersson et al, Nat Genet 2015) epigenetic mutations were absent in infant ALL, but present in 20-35% of the other patients.RNA-sequencing identified the KMT2A-fusion in 56/58 cases, with low exonic coverage preventing detection of the fusion in two cases. The reciprocal KMT2A fusion was only expressed in 13/39 cases where it was predicted to be expressed based on karyotype or whole genome sequencing data with 11/13 cases having the KMT2A-AFF1 fusion gene. In addition, RNA-sequencing identified 6 in-frame and 12 out-of-frame fusion genes that had formed either as part of the KMT2A-R itself or that were independent genetic events. Further, a novel in-frame KMT2A-ACIN1 fusion was identified in a child aged 1 year with B-precursor ALL. ACIN1 encodes Apoptotic Chromatin Condensation Inducer 1 and the fusion was formed through an insertion of 14q11 into 11q23. ACIN1 is also rearranged as part of the ACIN1-NUTM1 that we identified in an infant with ins(15;14)(q22;q11.2q32.1) (Andersson et al Nat Genet 2015). To study the ability of KMT2A-ACIN1 to induce leukemia in mice, we injected retrovirally transduced mouse bone marrow cells containing the fusion into syngeneic mice and KMT2A-MLLT3 was used as control. All mice succumbed to disease at an average of 112 days for KMT2A-ACIN1 (n=12) and 63 days for KMT2A-MLLT3 (n=5) and mice displayed splenomegaly and leukocytosis with an immunophenotype indicative of AML. Primary leukemia cells isolated from moribund mice gave rise to leukemia in sublethally irradiated recipients with reduced disease latency. In conclusion, these results highlight the differential molecular patterns in KMT2A-R leukemia across infancy to adulthood thereby providing novel pathogenetic insight. DisclosuresNo relevant conflicts of interest to declare.

PB1673 FEASIBILITY AND OUTCOME OF ALLOGENEIC BONE MARROW TRANSPLANTATION IN ADULT PHI NEGATIVE ACUTE LYMPHOBLASTIC LEUKEMIA

Background:Acute lymphoblastic leukemia (ALL) is a rare disease in adults. Despite the novels therapies, clinical outcomes remain unsatisfactory. Bone marrow allograft still holds its place as a consolidation treatment for patients in complete remission in order to improve the prognosis and lengthen survival.Aims:We study in this work the feasibility and outcome of bone marrow allograft for adult Philadelphia chromosome negative ALL.Methods:Our study is retrospective including the cases of high‐risk adult ALL (HR) diagnosed in the hematology department of Hédi Chaker Hospital of Sfax during the period from January 2004 to December 2015. These patients were treated according to protocols inspired by GRAALL 2003 and 2005. The indication of bone marrow allograft is systematic in patients whose age are <50 years and having a compatible intrafamilial donor. For our patients we studied the allograft indication, the search for a family compatible HLA donor, the feasibility of the allograft and finally the result of this one which was carried out at the national center of bone marrow transplantation in Tunis.Results:Among the 36 cases of adult phi negative ALL treated with the GRAALL 2003 and 2005 protocols, 28 patients were in complete remission (CR) and 22 patients (79%) were classified as HR. Twenty patients had indication of bone marrow allograft (2 were> 50 years of age). Of the 20 patients who had an HLA study, 14 patients (70%) had a compatible HLA family donor. Allogeneic bone marrow allograft could only be performed for 9 patients: 64% of patients with a compatible HLA donor and 45% of patients with CR. For the 5 others the transplant could not be done for: relapsed before allograft for 2 cases and severe comorbidities for the 3 others. The median time to completion of the allograft was 15 weeks. Among the allografts, 6 patients (67%) were living in CR after a follow‐up of 74 months, one patient relapsed at 6 months post‐transplant and 2 patients died of acute GVH. Of the 19 non‐allograft CR patients, 6 patients were living in CR (31%) and 1 died during consolidation therapy and 12 relapsed. The 5‐year DFS of both allografted and non‐allografted patients was 72% and 21%, respectively.Summary/Conclusion:Despite the cost‐effectiveness of the intra‐familial HLA study (70% donor) in our study, allografting could only be performed for a small number of patients (45%), hence the need to expand the indication of allograft for subjects over 50 years old or perform a mini allograft, do the same haplo transplant and even expand donor sources on files (pheno‐identical donors). Two‐thirds of the allografted patients in our series did not relapse, an interesting result and comparable to the literature.

Targeting WEE1 to enhance conventional therapies for acute lymphoblastic leukemia

BackgroundDespite the recent progress that has been made in the understanding and treatment of acute lymphoblastic leukemia (ALL), the outcome is still dismal in adult ALL cases. Several studies in solid tumors identified high expression of WEE1 kinase as a poor prognostic factor and reported its role as a cancer-conserving oncogene that protects cancer cells from DNA damage. Therefore, the targeted inhibition of WEE1 kinase has emerged as a rational strategy to sensitize cancer cells to antineoplastic compounds, which we evaluate in this study.MethodsThe effectiveness of the selective WEE1 inhibitor AZD-1775 as a single agent and in combination with different antineoplastic agents in B and T cell precursor ALL (B/T-ALL) was evaluated in vitro and ex vivo studies. The efficacy of the compound in terms of cytotoxicity, induction of apoptosis, and changes in gene and protein expression was assessed using different B/T-ALL cell lines and confirmed in primary ALL blasts.ResultsWe showed that WEE1 was highly expressed in adult primary ALL bone marrow and peripheral blood blasts (n = 58) compared to normal mononuclear cells isolated from the peripheral blood of healthy donors (p = 0.004). Thus, we hypothesized that WEE1 could be a rational target in ALL, and its inhibition could enhance the cytotoxicity of conventional therapies used for ALL. We evaluated the efficacy of AZD-1775 as a single agent and in combination with several antineoplastic agents, and we elucidated its mechanisms of action. AZD-1775 reduced cell viability in B/T-ALL cell lines by disrupting the G2/M checkpoint and inducing apoptosis. These findings were confirmed in human primary ALL bone marrow and peripheral blood blasts (n = 15). In both cell lines and primary leukemic cells, AZD-1775 significantly enhanced the efficacy of several tyrosine kinase inhibitors (TKIs) such as bosutinib, imatinib, and ponatinib, and of chemotherapeutic agents (clofarabine and doxorubicin) in terms of the reduction of cell viability, apoptosis induction, and inhibition of proliferation.ConclusionsOur data suggest that WEE1 plays a role in ALL blast’s survival and is a bona fide target for therapeutic intervention. These data support the evaluation of the therapeutic potential of AZD-1775 as chemo-sensitizer agent for the treatment of B/T-ALL.

Prognostic Features of BCR-ABL Genetic Variations in Acute Lymphoblastic Leukemia

Background: Acute lymphoblastic leukemia (ALL) is a hematologic malignancy which results from accumulation of lymphoid progenitor cells in the bone marrow and/or extramedullary sites. Philadelphia chromosome (Ph1) positive ALL, a high-risk cytogenetic subset, accounts for 25% - 30% of adult ALL cases but occurs in less than 5% of children. We aimed with this study to detect BCR-ABL genes fusion, amplification and deletion in ALL patients, using extrasignal-fluorescence in situ hybridization (ES-FISH), and to assess their relation with other standard prognostic factors and therapeutic response. Patients and Methods: This study was carried out on 39 newly diagnosed ALL patients. All patients were subjected to: history, clinical examination and laboratory investigations, which included complete blood count (CBC), peripheral blood (PB), bone marrow (BM) examination, immunophenotyping and fluorescence in situ hybridization using extra-signal probe to detect BCR-ABL genes fusion. Results: This study showed statistical analysis of patients’ t(9; 22) with other factors revealed, significant association (p 35 years, hepatosplenomegaly, absence of lymphadenopathy, TLC ≥ 50 × 109/L, absolute PB blasts ≥ 4.4 × 109/L, immunophenotyping and other aberrations. Conclusion: BCR/ABL fusion gene analysis by ES-FISH may serve as a prognostic marker in adulthood ALL. The age, TLC and t(9; 22) represent the significant standard prognostic factors in relation to patients’ outcome.

Philadelphia Chromosome In Acute Lymphoblastic Leukemia

Background. Acute lymphoblastic leukemia (ALL) is a malignant disease of the bone marrow in which early lymphoid precursors proliferate and replace the normal hematopoietic cells of the marrow. Philadelphia chromosome (Ph)-positive ALL, a high-risk cytogenetic subset, accounts for 25-30% of adult ALL cases but occurs in less than 5% of children. We aimed with this study to detect Ph chromosome in acute lymphoblastic leukemia patients, using (FISH), and to assess their relation with other standard prognostic factors and therapeutic response. Patients and methods. This study was carried out on 39 newly diagnosed ALL patients. All patients were subjected to; History, clinical examination and Laboratory investigations, which included CBC (Complete Blood Count), P.BL.(Peripheral Blood) smear and BM(Bone Marrow) examination, immunophenotyping and Fluorescence in situ hybridization to detect Ph chromosome. Results. This study was carried out on 39 newly diagnosed ALL patients show: Statistical analysis of patients’ t(9;22) with other factors revealed significant association (p35 years, hepatosplenomegaly, absence of lymphadenopathy, TLC ≥50X109/L, absolute P.Bl blasts ≥4.4X109/L and immunophenotyping. Conclusion. Ph chromosome expression serve as a powerful prognostic marker in adulthood ALL, As ph +ve adult acute lymphoblastic leukemia has poor prognosis and can be used as prognostic indicators for therapeutic response

T-cell acute lymphoblastic leukemia with co-expression of CD56, CD34, CD117 and CD33: A case with poor prognosis.

T-cell acute lymphoblastic leukemia (ALL) is an aggressive hematological malignancy, accounting for ~25% of all adult cases of ALL. We herein report a case of T-cell ALL exhibiting aberrant CD34, CD56, CD33 and CD117 expression in addition to T-cell markers, which did not respond to induction treatment. A 55-year-old woman was admitted to our hospital with a sore throat unresponsive to medication for 1 month. The laboratory examination revealed pancytopenia and the peripheral blood smear examination revealed blast cells. On flow cytometric analysis, the blast cells were found to be positive for cytoplasmic CD3, CD2, CD5, CD7, CD34, CD56, CD33 and CD117, and negative for myeloperoxidase, CD13, CD11b, CD15, CD19, CD79a, CD22 and CD10. The patient was diagnosed with T-cell ALL according to the 2008 World Health Organisation classification. The patient did not respond to Hyper-cyclophosphamide, vincristine, adriamycin and dexamethasone (CVAD) course A treatment and succumbed to the disease during Hyper-CVAD course B treatment. To the best of our knowledge, this is the first report of aberrant co-expression of the natural killer cell marker CD56, myeloid cell markers CD117 and CD33 and stem cell marker CD34 in a patient with T-cell ALL. This appears to be associated with an unfavorable outcome, despite the use of intensive chemotherapy.

RBP2 Promotes Adult Acute Lymphoblastic Leukemia by Upregulating BCL2.

Despite recent increases in the cure rate of acute lymphoblastic leukemia (ALL), adult ALL remains a high-risk disease that exhibits a high relapse rate. In this study, we found that the histone demethylase retinoblastoma binding protein-2 (RBP2) was overexpressed in both on-going and relapse cases of adult ALL, which revealed that RBP2 overexpression was not only involved in the pathogenesis of ALL but that its overexpression might also be related to relapse of the disease. RBP2 knockdown induced apoptosis and attenuated leukemic cell viability. Our results demonstrated that BCL2 is a novel target of RBP2 and supported the notion of RBP2 being a regulator of BCL2 expression via directly binding to its promoter. As the role of RBP2 in regulating apoptosis was confirmed, RBP2 overexpression and activation of BCL2 might play important roles in ALL development and progression.

Characterization of immunophenotypic aberrancies in adult and childhood acute lymphoblastic leukemia: A study from Northern India.

Identification of aberrant antigen expression is important in characterizing neoplastic population among non.neoplastic bone marrow counterparts and further in the detection of minimal residual disease. (MRD). Flow cytometry (FCM) is an important tool in identifying aberrant phenotypes. Incidence of aberrant phenotypes varies considerably in independent studies and its association with prognostic factors is still debatable. To identify the prevalence of aberrant phenotypes on immunophenotyping in a large series of de novo acute lymphoblastic leukemia (ALL) and to evaluate any association with initial clinical and hematological features. In the current study, 303 patients of de novo ALL were included from the Department of Hematology, PGIMER, Chandigarh during the time period (July 2010 to June 2012). The immunophenotype of all cases of ALL was studied using FCM. Aberrant myeloid antigen expression was seen in 42.5% cases. Most frequent aberrant myeloid antigen was CD13 (32.2% cases), followed by CD33 (27.2% cases) and CD117 (18.5% cases). The expression of CD117 was relatively frequent in comparison to earlier reports which describe its rare expression. Adult T- ALL showed higher expression of CD33 and CD117 than pediatric T-ALL (P = 0.032 and 0.043, respectively). Myeloid antigen expression in ALL was associated with lower WBC count (P < 0.05) and lower number of peripheral blasts (P < 0.05). Expression of CD34 was higher in My + ALL group (P < 0.05) than My- ALL group. In summary, CD117 is a relatively frequently expressed myeloid marker contrary to earlier reports which describes its rare expression. Pediatric and adult ALL cases with low blast count and CD34 positivity are more likely to express aberrant myeloid markers. Current study also supports that myeloid antigen expression in both adult and pediatric ALL is not associated with adverse presenting clinical and biological features.

Exome Sequencing in a Family with Chronic Lymphocytic Leukemia, Mantle Cell Lymphoma and Autoimmune Disease Uncovers Potential Germline Risk-Alleles

We identified a Caucasian family with dense distribution of B-cell non-Hodgkin lymphoma (NHL) and autoimmune disease (Figure 1). Within the family, three siblings and their mother have B-cell NHL (three with chronic lymphocytic leukemia [CLL]; one with mantle cell lymphoma [MCL]), and four family members have autoimmune diseases (rheumatoid arthritis or multiple sclerosis). In addition, two family members have melanoma. To investigate the genetic factors involved in B-cell NHL in this family, we exome sequenced nine individuals, including two unaffected spouses as technical-artifact controls. Following best-practice guidelines, we performed joint variant calling, including an additional 135 European 1000Genome exomes as a set of background controls. [Display omitted] After variant quality control, a total of 676,137 sequence variants were identified. We also performed individual genotype quality control based on a minimum read depth of 10 and genotype quality of 40, resulting in 554,690 variants. For our initial prioritization, we required that variants be: absent in the spouse controls, have minor allele frequency (MAF) ≤ 0.05 in the 1000Genome exomes, and be shared by all four B-cell NHL cases. This resulted in 73 variants of potential interest.Of the 73 variants, seven were predicted to be damaging by either PROVEAN or SIFT, two by both algorithms and by PolyPhen2. These two potentially damaging variants reside in the genes CCDC144A and RRS1. The gene CCDC144A is located at chromosome 17p11.2, a known breakpoint region of the 17p deletion often seen in CLL tumor cells. The variant identified in this gene was rare (MAF = 0.001 in the NHLBI Exome Sequencing Project [ESP]) and was also seen in two additional family members (one with rheumatoid arthritis; a second with rheumatoid arthritis and melanoma). The gene RRS1 is located at chromosome 8q13.1, and has been shown to be important for proper chromosomal organization during mitosis. The variant identified in this gene was relatively rare (MAF = 0.041 in ESP) and was seen in the same, two additional family members. Of the remaining five variants predicted damaging by only one algorithm, of interest were two variants in the SGK223 gene on chromosome 8p23.1. SGK223 is a kinase and a component in the BCR-ABL1 signaling network that is present in most chronic myelogenous leukemia cases and a quarter of adult acute lymphoblastic leukemia cases. Both of the variants in SGK223 were also seen in three additional family members (one with rheumatoid arthritis; a second with rheumatoid arthritis and melanoma; a third with melanoma).In addition to prioritization by predicted function of coding variants, we explored the 73 variants for overlap with findings from published germ-line investigations of B-cell NHL. This identified one variant in the ACOXL gene at chromosome 2q13. The variant is relatively rare (MAF = 0.017 in dbSNP) and lies in the same gene and intron (17,016 base pairs upstream) as rs13401811, the associated SNP (p = 2.08 x 10-18) reported in a genomewide association study (GWAS) for CLL.Our ongoing analyses and prioritization of the variants in this extraordinary family reveal overlap with signals coming from GWAS studies and suggest some potentially damaging variants in genes not previously implicated in NHL. The potential risk-alleles identified in our preliminary findings could shed new light about the genes and genetic factors involved in NHL. DisclosuresNo relevant conflicts of interest to declare.

Mutation and expression of PAX5 gene in adult acute lymphoblastic leukemia

PAX5 is an important transcription factor of paired-box(PAX) family. The aim of this study was to investigate the mutations and expression of PAX5 and its clinical significance in adult patients with acute lymphoblastic leukemia (ALL). Reverse transcription polymerase chain reaction (RT-PCR) and genomic PCR were performed to detect the deletions of PAX5 and point mutations of PAX5 exon 2-10 in 101 cases of adult ALL and were confirmed by cloning and sequencing. In addition, quantitative PCR (qPCR) was performed to evaluate the expression of PAX5. Furthermore, the correlations of mutations and expression of PAX5 with clinical parameters were analyzed, and the prognostic significance was evaluated as well. The results showed that PAX5 mutations were observed in 8 of 101 (7.9%) patients with B-ALL. A total of 9 types of mutations were detected, including 4 types of deletions, 4 types of point mutations and 1 insertion mutation; percentage of patients with age ≥ 50 years was higher in PAX5 mutation group than in wide-type group (62.5% vs 21.5%,P = 0.031) . The statistical differences were observed in B-cell subtype, initial platelet count and immunophenotypes between high and low expression of PAX5 (P < 0.05) . In addition, patients with high expression of PAX5 had higher first complete remission rate (86.7% vs 62.5%, P = 0.030) and 6-month overall survival rate (75.0% vs 50.0%, P = 0.034) compared with patients with low expression of PAX5. It is concluded that deletion/insertion/point mutations and aberrant expression of PAX5 can be observed in adult patients with B-ALL. Mutations and aberrant expression of PAX5 correlated with clinical parameters and have important clinical significance.

High-Resolution Analysis of Chromosomal Alterations in Adult Acute Lymphoblastic Leukemia

Background: Chromosomal alterations occur frequently in acute lymphoblastic leukemia (ALL), affecting either the chromosome number or structural changes. These alterations can lead to inactivation of tumor suppressor genes and/or activation of oncogenes. The objective of this study was to identify recurrent and/or novel chromosomal alterations in adult ALL using single nucleotide polymorphism (SNP) array analysis. Methods: We studied 41 cases of adult ALL compared with healthy normal controls using SNP array. Results: Our analysis revealed 43 copy number variant regions, of which 44% were amplifications and 56% were deletions . The most common amplifications were on chromosome regions 8p23.1 (71%), 1q44 (66%), 1q23.3 (54%), 11q23.3 (54%), 12p13.33 (54%) and 8q24.21 (51%). On the other hand, the most common deletions were identified on chromosomes 1p31.1 (76%), 3q26.1 (68%), 11p11.12 (63%), 4q12 (59%), 19p13.2 (59%), 7q11.21 (56%), Xp22.33 (54%), 7q11.21 (51%) and 19p13.11 (51%). Conclusions: Amplification of chromosome 8p23.1 and deletion of chromosome 1p31.1 were the most frequently found alterations in this study. These chromosomal regions contain genes such as SPAG11B , DEFB104A , DEFB105A , DEFB107A , DEFB106A and SPAG11A . These potential genes may contribute to leukemogenesis in adult ALL. The cytogenetic and molecular mechanisms underlying these chromosome changes deserve further investigations. J Hematol. 2014;3(3):65-71 doi: http://dx.doi.org/10.14740/jh140w

New Gene Targets Detected By SNP Array Analysis In a Consecutive Series Of 215 Cases Of Adult Acute Lymphoblastic Leukemia

Pediatric acute lymphoblastic leukemia (ALL) has a very favorable prognosis, effective treatment protocols and display a cure rate of more than 80%. However, adult ALL is associated with a much poorer prognosis; the long-term survival rate for adult cases is only a mere 30-40%, decreasing with higher age. For an improved prognosis and better treatment stratification in adult ALL, it is important to identify acquired genetic aberrations that could be linked to outcome. We present here the largest SNP array analysis to date, covering 5 million markers with a resolution of 10kb to investigate a consecutive series of 215 adult ALL cases, including samples obtained at diagnosis and relapse. We detected characteristic deletions, such as CDKN2A, PAX5, IKZF1, ETV6, RB1, and EBF1 genes. In addition, the investigation uncovered several recurrent cryptic genetic events not previously implicated in adult ALL; the BCAT1, SERP2, RAB30, SRPR, ST3GAL4, ASS1, RASSF3, FUBP3, BCL11A, GAB1, LINGO2, TOX, and CXCR4 genes. Other frequent abnormalities included both partial and whole-chromosome uniparental isodisomies. Our findings provide insights into the leukemogenic process and may be clinically important in adult ALL. Disclosures:No relevant conflicts of interest to declare.

Therapy Related Acute Lymphoblastic Leukemia: Pethema Experience

BackgroundTherapy related acute lymphoblastic leukemia, a subset of secondary acute lymphoblastic leukemia has been estimated as accounting for between 1.2 and 6.9% of all adult acute lymphoblastic leukemia cases. It has been associated with an increased frequency of high risk cytogenetic alterations and with worse clinical outcomes. It has been suggested these patients should be included in high risk treatment protocols. MethodIn order to evaluate these characteristics in a group of similar patients we contacted centres working within the PETHEMA group to request data on patients diagnosed with ALL asking for clinical information including the presence or absence of previous neoplasia and of previous cytotoxic therapy along with treatment responses and survival data. ResultsWe received information on 429 patients of whom 22 had received cytotoxic therapy for a prior neoplasm.Patients were divided into group 1 with prior cytotoxic therapy, group 2 with prior neoplasia without cytotoxic therapy and group 3 de novo ALL. We found patients in group 3 to be younger than the other two groups Group 1( 55 years) Group 2 (65 years) Group 3 (34 years) (p=0.001). No statistically significant difference was shown for white cell count, cytopenias, CNS involvement, LDH or for B versus T immunophenotype. Nor did our series show a significant difference in the frequencies of high risk cytogenetics between the groups. Figures for complete remission [Group 1- 13 (93%); Group 2- 6 (75%); Group 3-346 (85%) p=0.477] were higher in group 1 therapy related ALL compared with de novo patients without reaching clinical significance. Nor was a statistically significant difference shown for 3 year overall survival [Group 1 (80%); Group 2 (38%); Group 3 (47%) p=0.151] , 3 year event free survival [Group 1 (67%); Group 2 (38%); Group 3 (42%) p=0.24] or for complete remission duration [Group 1 (75%);Group 2 (50%); Group 3 (60%) p=0.462] ConclusionApart from age, our series did not show an increase in poor risk clinical or cytogenetic features in therapy related ALL patients compared with de novo disease cases and nor was clinical outcome demonstrated to be worse. This would suggest that risk stratification should be carried out using currently recognized parameters without specifically taking into account the status of therapy related disease. Disclosures:No relevant conflicts of interest to declare.

MTHFR Gene Polymorphisms and the Risk of Acute Lymphoblastic Leukemia in Adults and Children: A Case Control Study in India.

Genetic polymorphisms in the methylene tetrahydrofolate reductase (MTHFR) gene have been associated with the development of acute leukemias and various malignancies. The role of MTHFR polymorphism in the development of pediatric acute lymphoblastic leukemia (ALL) has been extensively studied among north Indians in various settings, yet its association with acute leukemias remains unresolved. To evaluate the relationship between functional MTHFR polymorphisms, C677T and A1298C and possible effect on risk of ALL in adults and children in North Indian population by comparing them with healthy controls. DNA was isolated from peripheral blood of 184 ALL patients (33 adults, 151 children) and 155 controls and analyzed by a PCR-restriction fragment length polymorphism assay. The frequency of MTHFR 677CT and 1298 AC genotypes were significantly lower among adult ALL cases when compared to the controls. We found a 1.74-fold reduced risk of ALL in individuals with 1298AC polymorphic variant and a 9.17-fold decreased risk of adult ALL. However, no statistically significant difference was evident between the above polymorphisms and susceptibility to ALL in children. Polymorphisms in the MTHFR gene possibly modulate risk of ALL in north Indian adults but not in children, although larger studies are needed.

TP53 mutations are frequent in adult acute lymphoblastic leukemia cases negative for recurrent fusion genes and correlate with poor response to induction therapy

Acute lymphoblastic leukemia (ALL) is a disease of either B-cell (80–85%) or T-cell (20–25%) derivation. Several molecular aberrations (i.e. BCR-ABL1, MLL/AFF1, SIL/TAL1 and E2A/PBX1 ) confer an overall poor outcome.[1][1],[2][2] However, a proportion of patients do not carry known genetic

The Evolution of Malignant and Reactive γδ+T Cell Clones in Relapse T-ALL After Allogeneic Stem Cell Transplantation

AbstractAbstract 4672T-cell acute lymphoblastic leukemia (T-ALL) comprises 25% of adult acute lymphoblastic leukemia cases, and its outcome is poorly understood. To improve the outcome of patients with T-cell acute lymphoblastic leukemia (T-ALL), characterization of the biological features of T-ALL blast cells and the immune status of patients with T-ALL is needed to identify specific therapeutic strategies. Using a novel approach that is based on the combination of fine-tiling comparative genomic hybridization (FT-CGH) and ligation mediated PCR (LM-PCR), we molecularly identified a malignant ¦Ã¦Ä+T cell clone with a V¦Ä5D¦Ä2J¦Ä1 rearrangement that was paired with a V¦ÃI TCR and comprised a V¦Ã1V¦Ä5 T cell clone in relapse T-ALL patient. This malignant T cell clone was lost after chemotherapy, while the same malignant V¦Ä5 T cell clone revealed when disease relapse post allo-HSCT at 100 weeks (Figure 1). Using PCR and genescan analyses, the distribution and clonality of the TCRV¦Ã and TCRV¦Ä subfamilies were examined before and after allo-HSCT in a patient with T-ALL. A reactive T cell clone with a V¦Ä4D¦Ä3J¦Ä1 rearrangement was identified in all samples taken at different time points (i.e., 4, 8, 68, 100 and 108 weeks after allo-HSCT) (Figure 2). The expression of this V¦Ä4+ T cell clone was higher in the patient during complete remission post allo-SCT, and at disease relapse. In conclusion, the techniques used in this study established the sensitive detection of malignant and reactive T cell clones, and these identified T cell clones may serve not only as biomarkers for minimal residual disease detection but also as indicators for the anti-leukemia immune status in patients who achieve CR. [Display omitted] [Display omitted] Disclosures:Chen:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Huang:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Zheng:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Geng:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Hu:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Zhang:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Yang:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Weng:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Du:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding. Li:The study was supported by grants from the National Natural Science Foundation of China (No. 30871091 and 91129720) and the Fundamental Research Funds for the Central Universities (No. 21610603 and 21612116) and the Guangdong Science & Technology Project: Research Funding.

Therapy‐related acute lymphoblastic leukemia is more frequent than previously recognized and has a poor prognosis

Acute lymphoblastic leukemia (ALL) occurring in patients with a history of prior chemotherapy/radiotherapy exposure has been previously reported to be rare, accounting for <2.5% of ALL cases. All cases of adult ALL with a history of prior cytotoxic or radiation therapy at a leukemia referral center over a 13-year period were analyzed. Twenty-three cases, representing 6.9% of all ALL cases, were identified. Of these, 17 (74%) had at least 1 high-risk feature; 8 (35%) had MLL rearrangements, and 4 were BCR-ABL(+) . MLL rearrangements were correlated with CD15 expression and absence of CD10, and also tended to have a shorter mean latency period and more prior topoisomerase II exposure. Twenty-one patients received induction therapy, and 18 (86%) achieved a complete response, 17 with 1 induction. Six patients have relapsed and died, and 4 others died of other complications, 2 of these postallogeneic stem cell transplantation. Median disease-free survival (DFS) and overall survival (OS) were 27 and 13.6 months, respectively, and 3-year DFS and OS were 37.1% and 37.6%, respectively. The frequency of therapy-related ALL is higher than previously reported and has a poor prognosis, probably related to the high frequency of adverse risk features.

Detection of Common Chimeric Fusion Transcripts in Acute Lymphoblastic Leukemia (ALL) Patients Using Multiplex Reverse Transcriptase Polymerase Chain Reaction Assay: A North Indian Tertiary Care Centre Experience

Abstract 4234 Introduction:Chromosomal abnormalities constitute an important parameter to identify prognostically relevant subgroups in acute lymphoblastic leukemia (ALL). Many western studies report the incidence of common chimeric fusion transcripts as 30–35%, however the data regarding the Indian patients is very scarce. Aims and Objectives:The aim of the present study was to detect presence of common chimeric fusion transcripts of t(12;21), t(9;22), t(1;19) and t(4;11) in adult and pediatric ALL cases using the Multiplex RT-PCR assay. Materials and Methods:This prospective study included 100 consecutive ALL cases diagnosed during last one year; 54 patients were <12 years of age. Diagnosis of ALL was made on the basis of bone marrow (BM) examination and flowcytometric immunophenotypic (FCM-IP) analysis. Approximately 2 ml of peripheral blood (PB) sample or 0.5 ml of BM sample was collected in EDTA. RNA extraction and cDNA synthesis was performed using commercial kits, according to standard protocols. RT-PCR assay was carried out using primers specific to the fusion transcripts of TEL-AML1 t(12;21); BCR-ABL t(9;22); E2A-PBX t(1;19) and MLL-AF4 t(4;11). The results of RT-PCR and FCM-IP were blinded and compared later. Results:Out of the 100 cases enrolled in the study, 54% were pediatric and 46% adult cases. Among the pediatric ALL cases, 49 were diagnosed as B-lineage ALL, 3 T-lineage ALL and 2 Biphenotypic ALL. Whereas among the adult ALL cases, 30 were diagnosed as B-lineage ALL, 12 T-lineage ALL and 4 Biphenotypic ALL. A total of 26% showed positivity for various fusion transcripts: 13% each pediatric and adult cases being positive. Of the 12 positive pediatric B-lineage ALL cases, 8 were positive for TEL-AML1 transcripts, 1 for BCR-ABL transcripts, 1 for E2A-PBX transcripts and 2 for MLL-AF4 transcripts. Out of the 11 positive adult cases, 7 were positive for BCR-ABL transcripts, 2 were positive for TEL-AML1 transcripts and 1 each for E2A-PBX transcripts and MLL-AF4 transcripts. BCR-ABL transcripts were detected in 1 out of 2 pediatric biphenotypic ALL and 2 out of 4 adult biphenotypic ALL cases. None of the pediatric cases was positive for the MLL-AF4 transcripts. None of the 4 transcripts were detected in any T-lineage ALL. Conclusion:Results of our study are comparable to those of other western and Asian studies, with TEL-AML1 transcripts being the most common fusion transcripts seen in pediatric B-ALL cases and BCR-ABL in adult cases. However two Indian studies had reported much lower incidence of TEL-AML1 and MLL-AF4 transcript in B-ALL cases. Identification of good prognostic groups and rationalization of therapy assumes great importance in our set ups as many patients are economically under-privileged. Relationship of these transcripts to the prognosis of our ALL patients will be evaluated in future. Disclosures:No relevant conflicts of interest to declare.

Genomic profiling of adult acute lymphoblastic leukemia by single nucleotide polymorphism oligonucleotide microarray and comparison to pediatric acute lymphoblastic leukemia

Differences in survival have been reported between pediatric and adult acute lymphoblastic leukemia. The inferior prognosis in adult acute lymphoblastic leukemia is not fully understood but could be attributed, in part, to differences in genomic alterations found in adult as compared to in pediatric acute lymphoblastic leukemia. We compared two different sets of high-density single nucleotide polymorphism array genotyping data from 75 new diagnostic adult and 399 previously published diagnostic pediatric acute lymphoblastic leukemia samples. The patients' samples were randomly acquired from among Caucasian and Asian populations and hybridized to either Affymetrix 50K or 250K single nucleotide polymorphism arrays. The array data were investigated with Copy Number Analysis for GeneChips (CNAG) software for allele-specific copy number analysis. The high density single nucleotide polymorphism array analysis of 75 samples of adult acute lymphoblastic leukemia led to the identification of numerous cryptic and submicroscopic genomic lesions with a mean of 7.6 genomic alterations per sample. The patterns and frequencies of lesions detected in the adult samples largely reproduced known genomic hallmarks detected in previous single nucleotide polymorphism-array studies of pediatric acute lymphoblastic leukemia, such as common deletions of 3p14.2 (FHIT), 5q33.3 (EBF), 6q, 9p21.3 (CDKN2A/B), 9p13.2 (PAX5), 13q14.2 (RB1) and 17q11.2 (NF1). Some differences between adult and pediatric acute lymphoblastic leukemia were identified when the pediatric data set was partitioned into hyperdiploid and non-hyperdiploid cases and then compared to the nearly exclusively non-hyperdiploid adult samples. In this analysis, adult samples had a higher rate of deletions of chromosome 17p (TP53) and duplication of 17q. Our analysis of adult acute lymphoblastic leukemia cases led to the identification of new potential target lesions relevant for the pathogenesis of acute lymphoblastic leukemia. However, no unequivocal pattern of submicroscopic genomic alterations was found to separate adult acute lymphoblastic leukemia from pediatric acute lymphoblastic leukemia. Therefore, apart from different therapy regimen, differences of prognosis between adult and pediatric acute lymphoblastic leukemia are probably based on genetic subgroups according to cytogenetically detectable lesions but not focal genomic copy number microlesions.