Comparison of Measurable Residual Disease in Pediatric B-Lymphoblastic Leukemia Using Multiparametric Flow Cytometry and Next-Generation Sequencing

Measurable residual disease (MRD) testing, a standard procedure in B-lymphoblastic leukemia (B-ALL) diagnostics, is assessed using multiparametric flow cytometry (MFC) and next-generation sequencing (NGS) analysis of immunoglobulin gene rearrangements. We evaluated the concordance between eight-color, two-tube MFC-MRD the LymphoTrack NGS-MRD assays using 139 follow-up samples from 54 pediatric patients with B-ALL. We also assessed the effect of hemodilution in MFC-MRD assays. The MRD-concordance rate was 79.9% (N=111), with 25 (18.0%) and 3 (2.2%) samples testing positive only by NGS-MRD (MFC-NGS+MRD) and MFC-MRD (MFC+NGS-MRD), respectively. We found a significant correlation in MRD values from total nucleated cells between the two methods (r=0.736 [0.647-0.806], P<0.001). The median MRD value of MFC-NGS+MRD samples was estimated to be 0.0012% (0.0001%-0.0263%) using the NGS-MRD assays. Notably, 14.3% of MFC-NGS+MRD samples showed NGS-MRD values below the limit of detection in the MFC-MRD assays. The percentages of hematogones detected in MFC-MRD assays significantly differed between the discordant and concordant cases (P<0.001). MFC and NGS-MRD assays showed relatively high concordance and correlation in MRD assessment, whereas the NGS-MRD assay detected MRD more frequently than the MFC-MRD assay in pediatric B-ALL. Evaluating the hematogone percentages can aid in assessing the impact of sample hemodilution.

Patterns and prognostic impact of CNS infiltration in adults with newly diagnosed acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is highly associated with central nervous system (CNS) infiltration and can be associated with higher risk of relapse. Conventional cytology (CC) is the traditional method for diagnosing CNS infiltration, although the use of immunophenotyping by flow cytometry (FC) has gained prominence in recent years due to its higher sensitivity. Also, some authors have proposed that CSF contamination by a traumatic lumbar puncture (TLP) could have a clinical impact. This retrospective study accessed the impact of CNS infiltration by CC or FC on overall survival, event-free survival, and relapse rate. In a cohort of 105 newly diagnosed ALL patients, CNS1, CNS2, and CNS3 status were found in 84%, 14%, and 2%, respectively. We found that extramedullary disease at the diagnosis, higher leukocyte counts, and higher blast percentage were associated with a positive CC. Sensitivity and specificity of CC were 53% and 98%, respectively. Three-year overall survival was 42.5%. Conversely, TLP was not associated with a positive CC nor had an impact on relapse rates. In multivariate analysis, a positive CC was associated with an increased relapse rate (HR 2.074, p = 0.037), while its detection by FC did not associate with this endpoint. Survival rates seem to be increasing over the last years by the adoption of a stratified CNS prophylaxis risk strategy. CSF contamination does not represent a major concern according to our report, as it did not increase CNS involvement or relapse rates.

INSPIRED Symposium Part 4A: Access to CAR T Cell Therapy in Unique Populations with B Cell Acute Lymphoblastic Leukemia

The approval of tisagenlecleucel (tisa-cel) for use in children with B cell acute lymphoblastic leukemia (B-ALL) was based on the phase 2 ELIANA trial, a global registration study. However, the ELIANA trial excluded specific subsets of patients facing unique challenges and did not include a sufficient number of patients to adequately evaluate outcomes in rare subpopulations. Since the commercialization of tisa-cel, data have become available that support therapeutic indications beyond the specific cohorts previously eligible for chimeric antigen receptor (CAR) T cells targeted to CD19 (CD19 CAR-T) therapy on the registration clinical trial. Substantial real-world data and aggregate clinical trial data have addressed gaps in our understanding of response rates, longer-term efficacy, and toxicities associated with CD19 CAR-T in special populations and rare clinical scenarios. These include patients with central nervous system relapsed disease, who were excluded from ELIANA and other early CAR-T trials owing to concerns about risk of neurotoxicity that have not been born out. There is also interest in the use of CD19 CAR-T for very-high-risk patients earlier in the course of therapy, such as patients with persistent minimal residual disease after 2 cycles of upfront chemotherapy and patients with first relapse of B-ALL. However, these indications are not specified on the label for tisa-cel and historically were not included in eligibility criteria for most clinical trials; data addressing these populations are needed. Populations at high risk of relapse, including patients with high-risk cytogenetic lesions, infants with B-ALL, patients with trisomy 21, and young adults with B-ALL, also may benefit from earlier treatment with CD19 CAR-T. It is important to prospectively study patient-reported outcomes given the differential toxicity expected between CD19 CAR-T and the historic standard of care, hematopoietic cell transplantation. Now that CD19 CAR-T therapy is commercially available, studies evaluating potential access disparities created by this very expensive novel therapy are increasingly pressing.

Updates on lymphoblastic leukemia/lymphoma classification and minimal/measurable residual disease analysis

Lymphoblastic leukemia/lymphoma (ALL/LBL), especially certain subtypes, continues to confer morbidity and mortality despite significant therapeutic advances. The pathologic classification of ALL/LBL, especially that of B-ALL, has recently substantially expanded with the identification of several distinct and prognostically important genetic drivers. These discoveries are reflected in both current classification systems, the World Health Organization (WHO) 5th edition and the new International Consensus Classification (ICC). In this article, novel subtypes of B-ALL are reviewed, including DUX4, MEF2D and ZNF384-rearranged B-ALL; the rare pediatric entity B-ALL with TLF3::HLF, now added to the classifications, is discussed; updates to the category of B-ALL with BCR::ABL1-like features (Ph-like B-ALL) are summarized; and emerging genetic subtypes of T-ALL are presented. The second half of the article details current approaches to minimal/measurable residual disease (MRD) detection in B-ALL and T-ALL and presents anticipated challenges to current approaches in the burgeoning era of antigen-directed immunotherapy.

Disseminated mucormycosis in a child with acute lymphoblastic leukemia: a case report and autopsy findings

Background

Mucormycosis is a rare infection caused by ubiquitous fungi of the Mucorales order that mainly affects immunocompromised patients. These fungi have an important tropism for blood vessels that allows them to spread rapidly and cause thromboembolic events.

Case report

We present a case of an 8-year-old male patient diagnosed with acute lymphoblastic leukemia treated with chemotherapy. He presented icteric syndrome, hepato-splenomegaly, and data of intestinal obstruction. Although he underwent intestinal resection, he did not improve and died. The autopsy identified disseminated mucormycosis involving the brain, lungs, esophagus, small intestine, colon, and pancreas.

Conclusions

Hematological neoplastic diseases and their treatment are important risk factors for developing infections by opportunistic microorganisms such as mucormycosis. Early diagnosis and adequate treatment are essential due to their intrinsic difficulty and the high mortality rate of these cases.

Behavioral and Emotional Functioning of Children and Adolescents at the End of Treatment for Acute Lymphoblastic Leukemia Compared to Healthy Peers

This study describes the behavioral and emotional adjustment of 77 children and adolescents 3 months post-treatment for acute lymphoblastic leukemia (ALL), compared to 52 age and sex-matched healthy peers. Parents, teachers, and self-report ratings on the Behavioral Assessment System for Children, Second Edition (BASC-2) were utilized to measure psychological function. While overall mean scores were in the average range for both groups, parents and teachers rated patients higher on behavior symptoms, internalizing problems and adaptive skill difficulties. No significant differences between groups were observed on self-report, and inter-rater correlations were low to moderate. For the ALL group, maternal university completion was associated with elevations on parent report of behavioral problems, while no other factors predicted either parent or teacher report on other scales. Findings indicate that a subset of patients will require specialist psychosocial support to optimise their adjustment following treatment completion.

Update on Lymphoblastic Leukemia/Lymphoma

Lymphoblastic leukemias/lymphomas are predominantly diseases of childhood, where they represent almost all acute leukemias; however, they are also encountered with significant frequency in the adult population. These neoplastic processes can be of B-cell or T-cell derivation and are composed of immature precursors of either lineage. The classification of B-lymphoblastic neoplasms relies predominantly on genetic and molecular findings, whereas the same is not true for those of T-lymphoid origin. Many of these recurrent cytogenetic abnormalities have important prognostic and therapeutic implications.

Trace Elements in Children with Acute Lymphoblastic Leukemia

OBJECTIVE

Although combined chemotherapy regimen leads to 80% remission in children with acute lymphocytic leukemia (ALL), malnutrition and altered serum trace elements as a consequence of chemotherapy agents, have become the new issue to deal with. With the aim to evaluate each trace element in childhood ALL, we investiguâtes six main trace elements before and after induction chemotherapy while considering age, gender and chemotherapy protocol as confounding factors.

METHODS

Thirty-six newly diagnosed ALL children were recruited, and trace elements were assessed by atomic absorption spectrometry technique. Trace elements (Zinc, Copper, Manganese, Magnesium, Chromium and Iron) decreased significantly after induction chemotherapy.

RESULTS

Considering the confounding factors, mean difference of elements decreased significantly, except for Chromium. Its mean difference was only significant in children younger than 10 and those who had received standard risk chemotherapy.

CONCLUSION

In conclusion, all the studied trace elements decreased significantly after induction chemotherapy session in ALL children. This highlights the importance of complementary and supplementary management. A larger cohort study with longer follow up is warranted to elucidate the long-term effect of chemotherapy on these trace elements on the general health status, quality of life or risk of relapse in ALL children.

FLT3-ITD and CD135 Over-Expression are Frequent Findings of Poor Survival in Adult Patients with Acute Leukemias

BACKGROUND

Fms-like tyrosine kinase 3 (FLT3) expression and mutation have been considered a poor prognostic factor in acute myeloid leukemia (AML). FLT3-ITD mutation is present in 30% of adult patients with AML and 2-5% in childhood acute lymphoblastic leukemia (ALL). The impact of these mutations on the prognosis of ALL patients, has not yet been established. Moreover, a limited number of publications regarding the level of expression of the FLT3 receptor (CD135) in both leukemias exist. This study aimed to analyze the clinical outcomes associated to the presence of FLT3-ITD mutation and the expression of CD135.

METHODS

82 adult patients with newly diagnosed acute leukemia (39 with AML and 43 with ALL) were included. Flow cytometry and RT-PCR were done to analyze the expression of CD135 and the presence of FLT3 ITD mutation, respectively.

RESULTS

FLT3-ITD was present in 14 (36%) of AML and 15 (35%) of ALL patients. Disease free survival (DFS) and overall survival (OS) were lower in ALL patients having a CD135 expression >3000 cells/μL. There was a trend for poor OS in AML patients expressing FLT3 ITD. OS was worse in AML patients with high expression of CD135.

CONCLUSION

A higher (35%) frequency of FLT3-ITD was found in adult ALL patients. The presence of FLT3-ITD was associated with a trend of poor OS in AML cases, and overexpression of CD135 was correlated with poor DFS in ALL cases and poor OS in both acute leukemias.

Cesarean section and risk of childhood leukemia: a systematic review and meta-analysis

BACKGROUND

A large number of studies pointed that being delivered by cesarean section (CS) would affect the health outcomes of offspring, however, whether CS would affect the risk of childhood leukemia remained uncertain. This study conducted a meta-analysis to quantitatively evaluate whether being delivered by CS would influence the onset of childhood leukemia.

METHODS

PubMed, Embase and Web of Science databases were searched from 3rd June, 1950 to 13th October, 2019 to identify the literature, which examined the relationship between CS and childhood leukemia. This study used Newcastle-Ottawa Scale to assess the quality of literature. Subgroup analyses were conducted on region, mode of delivery, design of the study and number of confounders adjusted. Egger's test and Begg's test were performed to evaluate possible publication bias.

RESULTS

The pooled odds ratio (OR) estimates illustrated that children delivered by CS had a higher risk of developing leukemia [OR 1.10, 95% confidence interval (CI) 1.04-1.17, P = 0.002] and lymphoblastic leukemia (OR 1.12, 95% CI 1.03-1.23, P = 0.009), while a significant association for myeloid leukemia was not observed (OR 1.05, 95% CI 0.92-1.20, P = 0.451). Results of subgroup analyses indicated that elective CS would increase the risk of childhood lymphoblastic leukemia (OR 1.16, 95% CI 1.06-1.27, P = 0.002). However, a statistical relationship between emergency CS and lymphoblastic leukemia was not observed (OR 1.07, 95% CI 0.93-1.23, P = 0.364).

CONCLUSIONS

CS would increase the risk of childhood lymphoblastic leukemia. It is worth noting that subgroup analyses shows that elective CS rather than emergency CS increases the risk of lymphoblastic leukemia in offspring.

Determining the Significant Prognostic Factors for the Recurrence of Pediatric Acute Lymphoblastic Leukemia Using a Competing Risks Approach

Acute lymphoblastic leukemia (ALL) is the most common cause of cancer-related fatality among children. This study aimed to identify the significant prognostic factors for the incidence of pediatric ALL. This retrospective study, conducted from 2007 to 2016 in the Iranian city of Mashhad, enrolled 417 patients with ALL. The diagnosis was confirmed by Giemsa staining of bone marrow smears. The first recurrence was regarded as the event of interest and non-relapse mortality as the competing event through a three-parameter Gompertz model. The level of statistical significance for univariate and multivariate analyses was set at 0.2 and 0.05, respectively. The first recurrence occurred in 44 (10.6%) survivors. Disease-free survival and 5-year overall survival rates were 85.9% and 74%, correspondingly. The five-year incidence rate for the first recurrence was 11.5% in the presence of non-relapse mortality. Briefly, the characteristics of the Gompertz model conferred more effective prognostic factors. Age above 10 years (P=0.010), involvement of the central nervous system (P=0.050), a high white blood cell count (P=0.020), and tumor lysis syndrome (P=0.010) were the significant prognostic factors for the recurrence and mortality of ALL. Accordingly, careful monitoring in the administration of treatment protocols is suggested to reduce the risk of recurrence and death in these patients.

B-cell acute lymphoblastic leukemia in an elderly man with plasma cell myeloma and long-term exposure to thalidomide and lenalidomide: a case report and literature review

Background

The advent of the immunomodulatory imide drugs (IMiDs) lenalidomide and thalidomide for the treatment of patients with plasma cell myeloma (PCM), has contributed to more than a doubling of the overall survival of these individuals. As a result, PCM patients join survivors of other malignancies such as breast and prostate cancer with a relatively new clinical problem – second primary malignancies (SPMs) – many of which are a result of the treatment of the initial cancer. PCM patients have a statistically significant increased risk for acute myeloid leukemia (AML) and Kaposi sarcoma. IMiD treatment has also been associated with an increased risk of myelodysplastic syndrome (MDS), AML, and squamous cell carcinoma of the skin. However, within these overlapping groups, acute lymphoblastic leukemia (ALL) is much less common.

Case presentation

Herein, we describe an elderly man with PCM and a 14-year cumulative history of IMiD therapy who developed persistent pancytopenia and was diagnosed with B-cell acute lymphoblastic leukemia (B-ALL). He joins a group of 17 other patients documented in the literature who have followed a similar sequence of events starting with worsening cytopenias while on IMiD maintenance for PCM. These PCM patients were diagnosed with B-ALL after a median time of 36 months after starting IMiD therapy and at a median age of 61.5 years old.

Conclusions

PCM patients with subsequent B-ALL have a poorer prognosis than their de novo B-ALL counterparts, however, the very low prevalence rate of subsequent B-ALL and high efficacy of IMiD maintenance therapy in PCM should not alter physicians’ current practice. Instead, there should be a low threshold for bone marrow biopsy for unexplained cytopenias.

Better survivals in adolescent and Young adults, compared to adults with acute lymphoblastic leukemia - A multicenter prospective registry in Thai population

Adult acute lymphoblastic leukemia (ALL) is an uncommon hematologic malignancy with high relapse and mortality rate. This study aimed to describe characteristics and outcomes of Thai ALL patients, and to determine the differences between adolescent and young adult (AYA) and adult ALL. ALL patients aged > 15 years were prospectively enrolled from 2015 to 2017. AYA patients were defined as age ≤ 39 years. Out of the 188 enrolled ALL patients, 9 were excluded due to changes in diagnosis or incomplete data. From the remaining 179 patients, 103 (57.5%) were AYA and 76 (42.5%) were adult. AYA ALL patients were predominantly male, had higher T-cell phenotype, higher white blood cells and hemoglobin, with lower frequency of Philadelphia chromosome or BCR-ABL1 mutation. All patients received treatment by adult hematologist, however 40.8% of AYA ALL patients were treated with pediatric adapted protocol. The effects of stem cell transplantation (SCT) and age were determined by stratified patients as: AYA - no SCT 91 (51.1%), AYA - SCT 12 (6.7%), adult - no SCT 64 (36.0%) and adult - SCT 11 (6.2%). The 2-year overall survival were: 53.9%, 60.6%, 39.2% and 70.1%, respectively. The 2-year event-free survival were: 45.0%, 54.0%, 21.0% and 49.9%, respectively. This is a large multicenter ALL cohort study conducted in Thailand. Patients who underwent SCT showed significantly improved OS and EFS, confirming the benefit of graft-versus-leukemia effect in ALL. However, further studies with longer follow-up, expanded use of SCT, use of molecular data, and minimal residual disease status are warranted.

Improving brain function of pediatric acute lymphoblastic leukemia patients after induction chemotherapy, a pilot self-contrast study by fractional amplitude of low-frequency fluctuation

Our previous study revealed altered resting-stated brain function in children with acute lymphoblastic leukemia (ALL) on new-onset stage. To investigate the effects after induction chemotherapy, a pilot self-contrast study was conducted to compare the difference in resting-stated brain function between pre- and post-induction chemotherapy of ALL. Fractional amplitude of low-frequency fluctuation (fALFF) was employed for fMRI data analysis. Clinical and resting state functional magnetic resonance imaging (RS-fMRI) data of 14 new-onset pediatric ALL patients were collected before and after 3 months of induction chemotherapy. Fourteen age- and gender-matched healthy controls (HCs) were recruited for comparison. Before induction chemotherapy, fALFF values of ALL patients decreased globally, especially in the default mode network (DMN), left frontal lobe, left occipital lobe, and bilateral postcentral gyri as compared to HCs. After induction chemotherapy, fALFF values of ALL patients decreased significantly in the bilateral cuneus, left lingual and calcarine gyri, and left mid frontal gyrus. Paired-sample t-tests and self-contrast analysis showed fALFF increased in the left precuneus, bilateral cuneus, left occipital lobe, bilateral frontal gyri, and bilateral temporal lobes, whereas fALFF in the bilateral precuneus decreased in the ALL patients after induction, which suggests potential side-effects of the treatment. The alteration of fALFF values suggested that resting brain function was impaired before induction chemotherapy and mostly recovered after treatment. This study suggested that fALFF is a reliable and feasible tool in detecting spontaneous brain activity to monitor early neurocognitive impairments in pediatric ALL to better understand the underlying neurobiological mechanisms of chemotherapy on the brain.

Lymphoblastic leukemia following myelodysplastic syndromes or myelodysplastic/myeloproliferative neoplasms

Lymphoblastic leukemia (ALL) following myelodysplastic syndrome (MDS) or myelodysplastic/myeloproliferative neoplasm (MDS/MPN) is very rare. We report five cases: four had ALL diagnosed after MDS or MDS/MPN and one had ALL and MDS diagnosed simultaneously. At the onset of ALL, all patients showed co-existing MDS or MDS/MPN. Map-back FISH was performed in four patients, showing that ALL and MDS were cytogenetically related in two patients and unrelated in the other two patients. All five patients were treated with ALL-based chemotherapies, two patients with ALL clonally related to MDS were refractory to the therapies, whereas the other three patients achieved remission. We conclude that ALL developed after MDS is extremely rare. In some patients, ALL is clonally related to MDS and these patients may be refractory to ALL-based chemotherapies. In other patients who have no evidence of clonal relation between ALL and MDS, these patients more likely respond to ALL-based treatment regimens.

Therapy-related myeloid neoplasm in an 18-year-old boy with B-lymphoblastic leukemia

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Acute myeloid leukemia or myelodysplastic syndrome during the course of ALL is a rare entity. Some of these cases are therapy-related while the others occur due to lineage switch. The correct diagnosis relies on comparing the immunophenotypes and cytogenetic/molecular alterations of the myeloid neoplasm and the ALL. We present the clinical, pathologic and cytogenetic features of a case of an 18-year-old male with prior treatment for B-lymphoblastic leukemia (B-ALL) who developed therapy-related myeloid neoplasm (t-MN) 4-5years after his initial diagnosis of B-ALL.

CASE PRESENTATION

A 13-year-old boy with no significant past medical history presented to Harbor-UCLA Medical Center (HUMC) in November 2012 with night sweats, fevers and chills, nausea, vomiting, diarrhea, fatigue, weakness, and weight loss. Peripheral blood flow cytometric analysis disclosed B-ALL. The blasts expressed CD10, CD19, CD22 (dim), CD34, CD38, HLA-DR, and TdT, and were negative for CD20, CD13, CD33, CD117, and cytoplasmic MPO. Chromosomal analysis and a supplemental fluorescence in situ hybridization (FISH) study performed on the bone marrow aspirate showed an abnormal karyotype (47,XY,+X,del(9)(p21p21)[4]/46,XY[16]). He achieved remission after induction chemotherapy and remained in remission until March 2016 when bilateral testicular masses were noted. Biopsy of the left testicular mass showed relapsed B-ALL. Cerebrospinal fluid (CSF) contained rare TdT-positive blasts, suggestive of minimal/early involvement by B-ALL. However, there was no evidence of acute leukemia in his bone marrow at this time. He was then treated with COG protocol AALL1331 randomized to blinatumomab arm and achieved second remission. In June 2017, the patient's peripheral blood smear showed 11% circulating monoblasts. By flow cytometry, the blasts expressed CD4, CD11b, CD13, CD15, CD33, CD38, CD56, and CD64. In addition, a few TdT-positive blasts were seen in his CSF cytospin smear. Bone marrow biopsy was subsequently performed which was consistent with evolving acute myeloid leukemia. A diagnosis of myeloid neoplasm, consistent with t-MN was made. Chromosomal analysis and FISH studies performed on his bone marrow aspirate showed normal karyotype (46,XY[20]), negative FISH result for deletion 9p21 locus, and positive KMT2A (MLL) rearrangement, respectively. Despite of chemotherapy, the patient died within one month after diagnosis.

DISCUSSION AND CONCLUSION

Diagnosis of t-MN should be suspected in patients with a history of receiving cytotoxic agents and/or irradiation. In this case study, we diagnosed t-MN with KMT2A rearrangement in a patient with history of B-ALL with 9p deletion and gain of X chromosome. Unusual features associated with this case are discussed.

Differential expression of MUC4, GPR110 and IL2RA defines two groups of CRLF2-rearranged acute lymphoblastic leukemia patients with distinct secondary lesions

CRLF2-rearrangements (CRLF2-r) occur frequently in Ph-like B-ALL, a high-risk ALL sub-type characterized by a signaling profile similar to Ph + ALL, however accumulating evidence indicates genetic heterogeneity within CRLF2-r ALL. We performed thorough genomic characterization of 35 CRLF2-r cases (P2RY8-CRLF2 n = 18; IGH-CRLF2 n = 17). Activating JAK2 mutations were present in 34% of patients, and a CRLF2-F232C mutation was identified in an additional 17%. IKZF1 deletions were detected in 63% of cases. The majority of patients (26/35) classified as Ph-like, and these were characterized by significantly higher levels of MUC4, GPR110 and IL2RA/CD25. In addition, Ph-like CRLF2-r samples were significantly enriched for IKZF1 deletions, JAK2/CRLF2 mutations and increased expression of JAK/STAT target genes (CISH, SOCS1), suggesting that mutation-driven CRLF2/JAK2 activation is more frequent in this sub-group. Less is known about the genomics of CRLF2-r cases lacking JAK2-pathway mutations, but KRAS/NRAS mutations were identified in 4/9 non-Ph-like samples. This work highlights the heterogeneity of secondary lesions which may arise and influence intracellular-pathway activation in CRLF2-r patients, and importantly presents distinct therapeutic targets within a group of patients harboring identical primary translocations, for whom efficient directed therapies are currently lacking.

Neurological Complications of the Leukemias Across the Ages

PURPOSE OF REVIEW

Acute and chronic leukemias are heterogeneous diseases and can affect any part of the body upon initial discovery. Understanding the sequela of systemic involvement is key for proper diagnosis and treatment.

RECENT FINDINGS

Over the decades, new research has emerged regarding neurological complications of the myeloid or lymphoid leukemias. Central nervous system involvement usually confers a poor prognosis and requires emergent treatment. Standard of care still involves systemic therapy, intrathecal administration of chemotherapeutic agents, and cranial radiation. Treatment-related side effects can occur and need to be recognized by any practitioner involved with patient care. It is imperative to understand neurologic complications from leukemia to prevent delays and initiate necessary treatment to maintain neurologic and cognitive function.

Antiproliferative and Apoptosis-Inducing Activities of Thymoquinone in Lymphoblastic Leukemia Cell Line

Acute lymphoblastic leukemia is one of the malignant proliferations of lymphoid cells in the early stages of differentiation and accounts for about 80% of all cases of childhood leukemia. Side effects of available treatment are still main concern. Thymoquinone (TQ), a natural compound isolated from Nigella sativa, induces growth inhibition and apoptosis in several cancer cell lines. The aim of the present study was to investigate the effect of TQ alone and in combination with doxorubicine on the proliferation inhibition and apoptosis induction of TQ in a lymphoblastic leukemia cell line. Jurkat cell line was cultured in standard condition and with concentrations of TQ (0-30 μm) and doxorubicine for 24, 48 and 72 h. Cell viability was measured by MTS assay. Apoptosis induction by TQ was assessed by annexin V-FITC/PI and flow cytometry analysis. TQ and DOX decreased cell viability with a time and dose dependent manner. The IC50 values were 19.461 ± 1.141, 17.342 ± 1.949 and 14.123 ± 1.874 μM in 24, 48 and 72 h, respectively for TQ. IC50 values for DOX were. 075 ± .0124, .028 ± .007 and.007 ± .001 μM in 24, 48 and 72 h, respectively. The level of cell apoptosis in all used concentrations of TQ (4, 8, 12, 16 and 20 μm) was higher than control group (10.2, 14.1, 36.6, 87.5 and 93.3% respectively after 24 h; 10.7, 13.9, 64.6, 92.2 and 93.1 respectively after 48 h; 2.83, 5.83, 41.4, 71.6 and 86.6% respectively after 72 h) and reached to a significant level at 12, 16 and 20 μm concentration for 24 and 48 h and 16 and 20 μm for 72 h incubation. Combination of doxorubicine and TQ lead to a synergistic cytotoxicity as compared to any of them alone. The study indicated that TQ is effective on proliferation inhibition and is a strong apoptotic inducer in Jurkat lymphoblastic cell line and has synergistic effect in combination with DOX. This combination strategy can be an alternative way for more powerful anticancer effects. Therefore, the study of the mechanism of apoptosis induction of TQ can be a step forward to in target therapy which might be considered in the future studies.

Conserved hierarchical gain of chromosome 4 is an independent prognostic factor in high hyperdiploid pediatric acute lymphoblastic leukemia

BACKGROUND

High hyperdiploid (HeH) pre-B pediatric acute lymphoblastic leukemia (B-pALL) is known to be heterogeneous by prognosis, but the stratification principals according to conventional cytogenetic analysis (CCA) are equivocal.

PROCEDURE

Untreated bone marrow samples of 214 B-pALL patients were previously classified according to the modal numbers (iMN₈) based on the gains of the chromosomes 4, 6, 10, 14, 17, 18, 21, and X as revealed by consecutive and correlated 2×4 color interphase fluorescence in situ hybridization, and at least five years of follow up data were analyzed.

RESULTS

Data from 48 of the 53 HeH (iMN₈>50) B-pALL patients indicated that among the age, gender, WBC, and iMN₈ parameters, only the last was significantly associated with overall survival (pOS), which allowed the cases to be classified as iMN₈ 51-54 (75%) and iMN₈ ≥ 55 (95%). Among the specific chromosomal gains of +4, +4/+6, +4/+17 and +4/+18, the first exhibited the most significance in terms of beneficial outcomes. The better prognostic group according to the iMN₈ was associated with a significantly reduced complexity of the subclonal landscape. However, iMN₈ did not prove to be an independent variable but was instead overridden by isolated trisomy of chromosome 4.

CONCLUSIONS

These data indicate that the better outcomes in the HeH B-pALL group arose from the gain of a specific chromosome that always ranks at the same position in the sequential acquisition of the affected chromosomes.

Investigating Effects of Acidic pH on Proliferation, Invasion and Drug-Induced Apoptosis in Lymphoblastic Leukemia

Some studies have shown that extracellular pH in tumors, which results in tumor progression, is less than that in normal tissues. The aim of this study was to investigate the effects of extracellular acidic pH on proliferation, invasion, and drug-induced apoptosis in acute lymphoblastic cells. The cells were cultured in different pH (pH 6.6 and pH 7.4) for 12 days. Cell proliferation was assessed by MTT assay and cell invasion was assayed by invasion assay and gene expression analysis of MMP-9. Drug-induced apoptosis was evaluated after exposure to doxorubicin for 24 hours by annexin V/PI staining and gene expression analysis of BAX pro-apoptotic protein. The results indicated the enhanced growth and invasion of leukemic cells at pH 6.6 (P ≤ 0.05). Furthermore, the cells at pH 6.6 were resistant to apoptosis by doxorubicin (P ≤ 0.05). It can be concluded that acidic pH increases the proliferation, invasion and reduces the drug-induced apoptosis in acute lymphoblastic leukemia. Extracellular acidity can influence the behavior of leukemic cells and therefore, the manipulation of extracellular liquid can be selected as a therapeutic strategy for leukemia, especially for acute lymphoblastic leukemia.

Keep in Mind Quality of Life: Outcome of a Ten-Year Series of Post-Transplantation Early Relapses in Childhood Acute Lymphoblastic Leukemia-A Report from the Grand Ouest Oncology Study Group for Children in France

Relapses of acute lymphoblastic leukemia (ALL) early after hematopoietic stem cell transplantations in children are uncommon but associated with a very poor prognosis. Whereas there are no current recommendations for the management of these relapses, the children's quality of life is an important issue. We studied the outcomes, including 1-year overall survival, complete remission, and quality of life, of 19 children with ALL who relapsed within the first year after their transplantation treated in the 5 participating centers between 2000 and 2011 Patients were distributed as follows: supportive care only (group A), outpatient treatment (mainly steroid and vincristine, group B), or intensive inpatient treatment (group C). There were no significant differences in 1-year overall survival (31.5% for the entire cohort) or remission rate for time between transplantation and relapse (< 6 months or 6 to 12 months), transplantation or disease characteristics, or treatment group. However, time spent in hospital (for treatment and complications) significantly differed between treatment groups B and C (20.8% ± 13.0 versus 59.1% ± 32.9, respectively; P < .05). No differences in organ toxicities, school attendance, or Lansky scores were found between treatment groups. Our sample size-limited data indicate, in a prepersonalized medicine era, that children treated with steroid and vincristine have the same prognosis as those treated with intensive therapy, but they may benefit from improved quality of life. Nevertheless, new therapeutic strategies are required and future prospective trials would help to establish recommendations.

Detection of BCR-ABL1 mutations that confer tyrosine kinase inhibitor resistance using massively parallel, next generation sequencing

Detection of BCR-ABL1 mutations that confer resistance to tyrosine kinase inhibitors is important for management of patients with t(9;22);BCR-ABL1-positive (Ph+) leukemias. Testing is often performed using Sanger sequencing (SS) which has relatively poor sensitivity. Given the widespread adoption of next generation sequencing (NGS), we sought to reevaluate the testing in the context of NGS methods. We developed an NGS-based BCR-ABL1 mutation test on the Ion Torrent Personal Genome Machine (PGM) to test for resistance mutations, primarily in the kinase domain in BCR-ABL1. We analyzed 508 clinical samples from patients with Ph+ leukemias. In a subset of these samples (n = 97), we conducted a comparison of the NGS results to a classical SS-based test. NGS facilitated detection of low-level mutations (<20 % allele frequency) that were not detectable by SS. In a subset of cases with multiple mutations, NGS was also able to determine if two mutations were on the same molecule (compound) or on separate molecules (polyclonal) but this was limited by the distance between mutated positions and by the effects of apparent distance-dependent PCR recombination. We found 22 compound mutations that centered on one or two key residues including two novel compound mutants: Q252H/Y253H and F311Y/F359I. The advantages of NGS make it a superior method for inventorying BCR-ABL1 resistance mutations. However, data analysis may be complicated by short read lengths and the effects of PCR recombination.

CD7 aberrant expression led to a lineage switch at relapsed childhood acute pre-B lymphoblastic leukemia

Immunophenotypic changes and lineage switch between diagnosis and relapse in acute lymphoblastic leukemia are uncommon and accompanied by poor outcomes. In this report, a 12-year-old boy with diagnosis of pre-B ALL with an aberrant expression of CD 7 is described. Patient was treated with the ALL-BFM 2000 protocol and suffered an episode of relapse with a lineage switch from pre-B ALL to T cell ALL. This report concludes that presence of aberrant expression of CD7 at diagnosis of pre-B ALL can have prognostic value of lineage switch to T cell ALL at relapse.

Prognostic significance of minimal residual disease detected by a simplified flow cytometric assay during remission induction chemotherapy in children with acute lymphoblastic leukemia

Purpose

Our study attempted to determine the prognostic significance of minimal residual disease (MRD) detected by a simplified flow cytometric assay during induction chemotherapy in children with B-cell acute lymphoblastic leukemia (B-ALL).

Methods

A total of 98 patients were newly diagnosed with precursor B-ALL from June 2004 to December 2008 at the Asan Medical Center (Seoul, Korea). Of those, 37 were eligible for flow cytometric MRD study analysis on day 14 of their induction treatment. The flow cytometric MRD assay was based on the expression intensity of CD19/CD10/CD34 or aberrant expression of myeloid antigens by bone marrow nucleated cells.

Results

Thirty-five patients (94.6%) had CD19-positive leukemic cells that also expressed CD10 and/or CD34, and 18 (48.6%) had leukemic cells with aberrant expression of myeloid antigens. Seven patients with ≥1% leukemic cells on day 14 had a significantly lower relapse-free survival (RFS) compared to the 30 patients with lower levels (42.9% [18.7%] vs. 92.0% [5.4%], P=0.004). Stratification into 3 MRD groups (≥1%, 0.1-1%, and <0.1%) also showed a statistically significant difference in RFS (42.9% [18.7%] vs. 86.9% [8.7%] vs. 100%, P=0.013). However, the MRD status had no significant influence on overall survival. Multivariate analysis demonstrated that the MRD level on day 14 was an independent prognostic factor with borderline significance.

Conclusion

An MRD assay using simplified flow cytometry during induction chemotherapy may help to identify patients with B-ALL who have an excellent outcome and patients who are at higher risk for relapse.