Leukemia and/or myeloproliferative syndrome in neonates with Down syndrome

The impact of Down syndrome-specific non-malignant hematopoietic regeneration in the bone marrow on the detection of leukemic measurable residual disease

BACKGROUND

Detection of measurable residual disease detection (MRD) by flow cytometry after the first course of chemotherapy is a standard measure of early response in patients with acute myeloid leukemia (AML). Myeloid leukemia associated with Down Syndrome (ML-DS) is a distinct form of AML. Differences in steady-state and regenerating hematopoiesis between patients with or without DS are not well understood. This understanding is essential to accurately determine the presence of residual leukemia in patients with ML-DS.

METHODS

A standardized antibody panel defined quantitative antigen expression in 115 follow-up bone marrow (BM) aspirates from 45 patients following chemotherapy for ML-DS or DS precursor B-cell acute lymphoblastic leukemia (B-ALL-DS) with the "difference from normal (ΔN)" technique. When possible, FISH and SNP/CGH microarray studies were performed on sorted cell fractions.

RESULTS

93% of BM specimens submitted post chemotherapy had a clearly identifiable CD34+ CD56+ population present between 0.06% and 2.6% of total non-erythroid cells. An overlapping CD34+ HLA-DRheterogeneous population was observed among 92% of patients at a lower frequency (0.04%-0.8% of total non-erythroid cells). In B-ALL-DS patients, the same CD34+ CD56+ HLA-DRheterogeneous expression was observed. FACS-FISH/Array studies demonstrated no residual genetic clones in the DS-specific myeloid progenitor cells.

CONCLUSIONS

Non-malignant myeloid progenitors in the regenerating BM of patients who have undergone chemotherapy for either ML-DS or B-ALL-DS express an immunophenotype that is different from normal BM of non-DS patients. Awareness of this DS-specific non-malignant myeloid progenitor is essential to the interpretation of MRD by flow cytometry in patients with ML-DS.

Transient abnormal myelopoiesis in Down syndrome: Experience of long term follow up from a single tertiary center in Thailand

Transient abnormal myelopoiesis (TAM) is a unique disease occurring in Down syndrome (DS) infants from which most patients have spontaneous remission. This study aimed to evaluate the incidence and outcomes of TAM in a tertiary center in Thailand. We reviewed the records of 997 DS patients diagnosed between June 1993 and October 2019. From the 997 DS patients, 32 had been diagnosed with TAM. The incidence of TAM was 3.2% and an overall survival rate of 87.5%. A total of 2/28 who survived (7.1%) subsequently developed AML-DS at the ages of 2.1 and 4.5 years, respectively. The risk factors related with death included maternal multiparity, sepsis, skin bleeding, subcutaneous nodules, high WBC count, low hemoglobin, and elevated AST level.Abbreviations.

Transient myeloproliferative disorder as the presenting feature for mosaic trisomy 21

Trisomy 21 is a common congenital disorder with well-documented clinical manifestations, including an increased risk for the transient myeloproliferative disorder as a neonate and leukemia in childhood and adolescence. Transient myeloproliferative disorder is only known to occur in hematopoietic cells with trisomy 21. Children with mosaic trisomy 21 also have a risk for hematological malignancies. We present a nondysmorphic neonate, with a negative noninvasive prenatal screening of maternal blood for trisomy 21, who came to medical attention because of ruddy skin. He was found to have mild polycythemia, thrombocytopenia, and developed peripheral blasts. His clinical presentation was consistent with transient myeloproliferative disorder, which is only seen with trisomy 21. Cytogenetic studies of peripheral blood are positive for mosaic trisomy 21.

Recommendations for Diagnosis and Treatment of Children with Transient Abnormal Myelopoiesis (TAM) and Myeloid Leukemia in Down Syndrome (ML-DS)

Children with Down syndrome are at a high risk of developing transient abnormal myelopoiesis (TAM; synonym: TMD) or myeloid leukemia (ML-DS). While most patients with TAM are asymptomatic and go into spontaneous remission without a need for therapy, around 20% of patients die within the first six months due to TAM-related complications. Another 20-30% of patients progress from TAM to ML-DS. ML-DS patients are particularly vulnerable to therapy-associated toxicity, but the prognosis of relapsed ML-DS is extremely poor - thus, ML-DS therapy schemata must strive for a balance between appropriate efficacy (to avoid relapses) and treatment-related toxicity. This guideline presents diagnostic and therapeutic strategies for TAM and ML-DS based on the experience and results of previous clinical studies from the BFM working group, which have helped reduce the risk of early death in symptomatic TAM patients using low-dose cytarabine, and which have achieved excellent cure rates for ML-DS using intensity-reduced treatment protocols.

Aberrant myelomonocytic CD56 expression in Down syndrome is frequent and not associated with leukemogenesis

Children with Down syndrome (DS) are at an increased risk of developing transient abnormal myelopoiesis (TAM) and acute leukemia. Aberrant expression of CD56 has been observed on myeloid leukemic blasts in DS patients. In general, CD56 expression in acute myeloid leukemia (AML) is considered a promoter of leukemogenesis. We did a retrospective flow cytometric study to investigate mature myelomonocytic cell CD56 expression patterns in TAM, non-TAM, and leukemia cases with DS. Flow cytometric analysis showed that granulocyte and monocyte aberrant/dysplastic CD56 expression is an inherent characteristic of most DS patients irrespective of the presence of TAM or leukemia. Increased CD56 expression in monocyte and granulocyte populations in DS could be multifactorial; greater expression of RUNX1 secondary to the gene dose effect of trisomy 21 along with the maturational state of the cells are the potential contributors. Unlike AML seen in non-DS patients, CD56 overexpression in DS AML cases does not appear to play a role in leukemogenesis.

Evaluation of biochemical and hematological parameters in adults with Down syndrome

Down syndrome (DS) is the most common worldwide cause of intellectual disability of genetic origin and the most common chromosomal disorder affecting live-born infants. In addition to intellectual disability, individuals with DS have other comorbidities and complex medical conditions. The increase in the life expectancy of patients with DS requires expanding the knowledge about their clinical characteristics and related laboratory parameters. Several studies exploring laboratory tests in DS patients exist, but their focus is limited to specific areas of metabolism. Therefore, our main goal was to describe the biochemical and hematological findings in a DS cohort and to compare the values to those of a control population. A total of 248 DS individuals and 84 control subjects were enrolled. DS individuals had a higher frequency of several clinical conditions compared to control individuals and presented with significant differences with respect to the controls in both biochemical and hematological parameters. We found age- and sex-related differences in several of the parameters. A good understanding of the differences in our cohort might be of aid in the clinical follow-up of adults with DS, especially considering that the lifespan of DS individuals may reach 60 years of age in developed countries.

Complete blood count differences in a cohort of Down syndrome neonates with transient abnormal myelopoiesis screened for GATA1 pathogenic variants

Transient abnormal myelopoiesis (TAM) raises the risk for acute myeloid leukemia of Down syndrome (DS) (ML-DS), and both are related to GATA1 pathogenic variants. Here, we analyzed which findings on complete blood count (CBC) are associated with TAM in a cohort of neonates with DS screened for GATA1 pathogenic variants. The CBCs were compared among 70 newborns with DS, including 16 patients (22.9%) with TAM (cases), and 54 patients (77.1%) without TAM (controls). TAM was defined as peripheral circulating blasts (PCBs) ≥ 1%. PCR and direct sequencing were used to screen DNA samples from peripheral blood for GATA1 exon 2 mutations. Multivariate logistic regression analyses determined that the mean count of lymphocytes was significantly higher in DS infants with TAM (p = .035) and that lymphocytosis confers a risk for TAM (adjusted odds ratio = 7.23, 95% confidence intervals: 2.02-25.92). Pathogenic variants of GATA1 were identified in 2 of 70 analyzed DS neonates (2.9%), of which one had ML-DS and another had an asymptomatic TAM. Among those DS infants with TAM, the GATA1 pathogenic variant detection was 12.5%. Our results indicated that lymphocytosis is associated with TAM in neonates with DS. However, since not all infants with an abnormal CBC had TAM, and not all infants with TAM had GATA1 pathogenic variants, we emphasize that only the search for GATA1 pathogenic variants allows the proper identification of the subgroup of DS infants with a real increasing in risk for ML-DS.

Acute Megakaryocytic Leukemia

Acute megakaryoblastic leukemia (AMKL) is a rare malignancy affecting megakaryocytes, platelet-producing cells that reside in the bone marrow. Children with Down syndrome (DS) are particularly prone to developing the disease and have a different age of onset, distinct genetic mutations, and better prognosis as compared with individuals without DS who develop the disease. Here, we discuss the contributions of chromosome 21 genes and other genetic mutations to AMKL, the clinical features of the disease, and the differing features of DS- and non-DS-AMKL. Further studies elucidating the role of chromosome 21 genes in this disease may aid our understanding of how they function in other types of leukemia, in which they are frequently mutated or differentially expressed. Although researchers have made many insights into understanding AMKL, much more remains to be learned about its underlying molecular mechanisms.

Recent advances in the understanding of transient abnormal myelopoiesis in Down syndrome

Neonates with Down syndrome (DS) have a propensity to develop the unique myeloproliferative disorder, transient abnormal myelopoiesis (TAM). TAM usually resolves spontaneously in ≤3 months, but approximately 10% of patients with TAM die from hepatic or multi-organ failure. After remission, 20% of patients with TAM develop acute myeloid leukemia associated with Down syndrome (ML-DS). Blasts in both TAM and ML-DS have trisomy 21 and GATA binding protein 1 (GATA1) mutations. Recent studies have shown that infants with DS and no clinical signs of TAM or increases in peripheral blood blasts can have minor clones carrying GATA1 mutations, referred to as silent TAM. Low-dose cytarabine can improve the outcomes of patients with TAM and high white blood cell count. A number of studies using fetal liver cells, mouse models, or induced pluripotent stem cells have elucidated the roles of trisomy 21 and GATA1 mutations in the development of TAM. Next-generation sequencing of TAM and ML-DS patient samples identified additional mutations in genes involved in epigenetic regulation. Xenograft models of TAM demonstrate the genetic heterogeneity of TAM blasts and mimic the process of clonal selection and expansion of TAM clones that leads to ML-DS. DNA methylation analysis suggests that epigenetic dysregulation may be involved in the progression from TAM to ML-DS. Unraveling the mechanisms underlying leukemogenesis and identification of factors that predict progression to leukemia could assist in development of strategies to prevent progression to ML-DS. Investigation of TAM, a unique pre-leukemic condition, will continue to strongly influence basic and clinical research into the development of hematological malignancies.

Distinct GATA1 Point Mutations in Monozygotic Twins With Down Syndrome and Transient Abnormal Myelopoiesis From a Triplet Pregnancy: A Case Report and Review of Literature

OBJECTIVES

Down syndrome (DS)-associated transient abnormal myelopoiesis (TAM) or acute megakaryoblastic leukemia (AMKL) in monozygotic twins is exceedingly rare and has not been well characterized.

METHODS

We describe a unique case of monozygotic twins with simultaneous TAM from a triplet pregnancy at 34 weeks' gestation. Previously reported cases of TAM and DS-AMKL in monozygotic twins have been reviewed to compare with our cases. The current concept of a sequential multistep process in leukemogenesis and disease evolution of TAM into DS-AMKL through the collaboration among trisomy 21, GATA1, and other gene mutations is also reviewed.

RESULTS

Distinct GATA1 mutations are identified in our neonate twins with TAM from a triplet pregnancy, whereas precisely identical GATA1 mutations have been detected in all three monozygotic DS twins reported in the literature.

CONCLUSIONS

Identical GATA1 mutations in cases of monozygotic twins are likely derived from twin-twin transmission. Distinct GATA1 mutations identified in our neonate twins with TAM provide unequivocal evidence of independent intra-utero GATA1 mutations, a completely different mechanism of development of TAM in monozygotic twins from previously reported cases. Interaction of trisomy 21 and GATA1 mutation produces TAM, but additional gene mutations are required for TAM to transform into DS-AMKL.

Screening for Hematological Disorders in Mosaic Down Syndrome: Parent Report of Experiences

Children with Down syndrome (DS) have increased risk for multiple medical conditions with published health care guidelines. Current guidelines do not specify whether or not they apply to mosaic DS (mDS). We surveyed families of patients with mDS regarding screening, including monitoring practices as well as complications identified. Hematological complications were similar to those reported in nonmosaic DS. Of 91 parents of children with mDS surveyed, only 69% had ever had a screening lab; only 57% had ever had a screening complete blood count (CBC). Younger children were less likely to be screened (for CBC, 50% of 0- to 3-year-olds vs 90% of 4- to 12-year-olds; P = 0.0036). Screening practices are suboptimal, with the youngest children at greatest risk. Comparing reported screening practices with physician adherence, there was discrepancy between perceptions of adherence and perceptions of practice. Children with mDS should be monitored on the same schedule as other children with DS.

Preoperative evaluation and comprehensive risk assessment for children with Down syndrome

Down syndrome is a common chromosome disorder affecting all body systems. This creates unique physiologic concerns that can affect safety during anesthesia and surgery. Little consensus exists, however, on the best way to evaluate children with Down syndrome in preparation for surgery. We review a number of salient topics affecting these children in the perioperative period, including cervical spine instability, cardiovascular abnormalities, pulmonary hypertension, upper airway obstruction, hematologic disturbances, prematurity, low birth weight, and the use of supplements and alternative therapies. Recommendations include obtaining a complete blood count to detect an increased risk for bleeding or stroke, and cardiology evaluation to identify patients with pulmonary hypertension, as well as undiagnosed or residual heart disease. Pediatric cardiac anesthesiologists and intensivists should be involved as needed. The potential for cervical spine instability should be considered, and the anesthesiologist may wish to have several options available both for the medications and equipment used. The child's family should always be asked if he or she is on any nutritional supplements, as some products marketed to families may have secondary effects such as inhibition of platelet function. Using this evaluation in presurgical planning will allow physicians to better consider the individual circumstances for their patients with Down syndrome. Our goal was to optimize patient safety by choosing the most appropriate setting and perioperative personnel, and to mitigate those risk factors amenable to intervention.

Insights into cell ontogeny, age, and acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogenous disease of hematopoietic stem cells (HSCs) and progenitor cells (HSPCs). The pathogenesis of AML involves cytogenetic abnormalities, genetic mutations, and epigenetic anomalies. Although it is widely accepted that the cellular biology, gene expression, and epigenetic landscape of normal HSCs change with age, little is known about the interplay between the age at which the cell becomes leukemic and the resultant leukemia. Despite its rarity, childhood AML is a leading cause of childhood cancer mortality. Treatment is in general extrapolated from adult AML on the assumption that adult AML and pediatric AML are similar biological entities. However, distinct biological processes and epigenetic modifications in pediatric and adult AML may mean that response to novel therapies in children may differ from that in adults with AML. A better understanding of the key pathways involved in transformation and how these differ between childhood and adult AML is an important step in identifying effective treatment. This review highlights both the commonalities and differences between pediatric and adult AML disease biology with respect to age.

Transient leukemia in a newborn without Down syndrome: case report and review of the literature

Transient neonatal leukemia occurs almost exclusively in Down syndrome babies. We report here the unusual case of a newborn without Down syndrome who presented neonatal transient leukemia and who achieved spontaneously complete remission. Trisomy 21 and GATA1 mutation were both present in leukemic cells. While close follow-up is advised since true leukemia may develop later, the patient is still in remission for 2.5 years. We performed a literature review of 15 other similar cases.

CONCLUSION

Our case of transient leukemia without Down syndrome and the literature review highlight the important role of trisomy 21 and GATA1 mutation in the development of transient neonatal leukemia.

Increased TERC gene copy number and cells in senescence in primary sclerosing cholangitis compared to colitis and control patients

OBJECTIVE

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disorder that involves inflammatory and fibrotic changes in the bile ducts. Up to 80% of patients have concomitant inflammatory bowel disease (IBD) with colitis. PSC patients are predisposed to develop hepatobiliary, colonic and other extrahepatic malignancies, probably related to inflammatory processes that might promote carcinogenesis. Telomerase is an enzyme complex that lengthens telomeres and has enhanced expression in numerous malignancies. In this study, we evaluated the TERC gene copy number, the proportion of cells in senescence and the amount of fragmentation in the senescent state.

METHODS

Fluorescence in situ hybridization (FISH) for the TERC gene was applied to lymphocytes retrieved from PSC (N=19), colitis (N=20) and healthy control patients (N=20) to determine the TERC copy number. On the same FISH slides, cells stained with DAPI were also analyzed for senescence-associated heterochromatin foci (SAHF) status, including the number of cells with fragments and the number of SAHF fragments in each cell.

RESULTS

A higher TERC gene copy number was observed in cells from PSC patients compared to colitis and control group patients. It was also higher in the colitis than in the control group. Significantly more cells in the senescent state and more fragmentation in each cell were observed in the PSC group compared to colitis and control groups.

CONCLUSION

The TERC gene copy number and the number of cells in the senescent state were increased in PSC patients compared to the colitis and control groups. These findings are probably related to the genetic instability parameters that reflect the higher tendency of this patient group to develop malignancies.

Transient leukemia-associated pericardial tamponade in a neonate with Down syndrome

Approximately 10% of neonates with Down syndrome may develop a form of megakaryoblastic leukemia that usually disappear spontaneously during the first months of the life. Although it seems to have a benign course, it may also be lethal and severe in some cases, especially in the form of hydrops and/or cardiopulmonary failure. Herein, we report a male infant with Down syndrome who was admitted with respiratory distress due to severe pericardial effusion leading to pericardial tamponade in the first 2 weeks of life. Pericardiosentesis and pericardial tube replacement in combination with steroid therapy was performed. He responded well to these therapies and his leukemia resolved on the fourth month of life. This case suggests that severe pericardial effusion and pericardial tamponade may be life-threatening complications of transient leukemia of Down syndrome and also it may be managed successfully with appropriate treatments.

Down syndrome with different hematological manifestations: a short series of 3 cases with review of literature

Children with Down syndrome (DS) present with a spectrum of hematolymphoid malignancies ranging from transient myeloproliferative disorder (TMD) which regress spontaneously to frank acute leukemia of both myeloid and lymphoid lineage. Here we present a series of three cases with different manifestation in DS. Three cases of DS presented with TMD, acute myeloid leukemia (AML-M2) and acute megakaryoblastic leukemia (AMKL), respectively. This case series displays the spectrum of hematological manifestations in children with DS. Although TMD and AMKL are strongly associated with DS, other AML subtypes can also be seen in such patients.

Natural history of transient myeloproliferative disorder clinically diagnosed in Down syndrome neonates: a report from the Children's Oncology Group Study A2971

Transient myeloproliferative disorder (TMD), restricted to newborns with trisomy 21, is a megakaryocytic leukemia that although lethal in some is distinguished by its spontaneous resolution. Later development of acute myeloid leukemia (AML) occurs in some. Prospective enrollment (n = 135) elucidated the natural history in Down syndrome (DS) patients diagnosed with TMD via the use of uniform monitoring and intervention guidelines. Prevalent at diagnosis were leukocytosis, peripheral blast exceeding marrow blast percentage, and hepatomegaly. Among those with life-threatening symptoms, most (n = 29/38; 76%) received intervention therapy until symptoms abated and then were monitored similarly. Organomegaly with cardiopulmonary compromise most frequently led to intervention (43%). Death occurred in 21% but only 10% were attributable to TMD (intervention vs observation patients: 13/14 vs 1/15 because of TMD). Among those solely observed, peripheral blasts and all other TMD symptoms cleared at a median of 36 and 49 days from diagnosis, respectively. On the basis of the diagnostic clinical findings of hepatomegaly with or without life-threatening symptoms, 3 groups were identified with differing survival: low risk with neither finding (38%), intermediate risk with hepatomegaly alone (40%), and high risk with both (21%; overall survival: 92% ± 8%, 77% ± 12%, and 51% ± 19%, respectively; P ≤ .001). Among all, AML subsequently occurred in 16% at a median of 441 days (range, 118-1085 days). The trial is registered at http://www.clinicaltrials.gov as NCT00003593.

Health supervision for children with Down syndrome

These guidelines are designed to assist the pediatrician in caring for the child in whom a diagnosis of Down syndrome has been confirmed by chromosome analysis. Although a pediatrician's initial contact with the child is usually during infancy, occasionally the pregnant woman who has been given a prenatal diagnosis of Down syndrome will be referred for review of the condition and the genetic counseling provided. Therefore, this report offers guidance for this situation as well.

Telomeres in trisomy 21 amniocytes

Individuals with trisomy 21 have an increased risk of developing leukemia and premature dementia. They also have a higher rate of telomere loss. The aim of the study was to compare telomere length and the hTERC gene copy number, which encodes the telomerase RNA subunit, in amniocytes of trisomy 21 conceptions and normal pregnancies. A quantitative fluorescence-in-situ protocol (Q-FISH) was used to compare telomere length in amniocytes cultured from 11 trisomy 21 conceptions and from 14 normal pregnancies. Quantification was conducted using novel computer software. Fluorescence in situ hybridization (FISH) was used to assess the percentage of cells with additional copies of hTERC. We found that the immunofluorescence intensity, which represents telomere length, was significantly lower in amniocytes from trisomy 21 conceptions compared to the control group. The trisomy 21 group had a higher number of cells with additional copies of hTERC. This observation could be one of the cytogenetic parameters that represent a state of genetic instability and might play a role in the pathomechanism of typical features of Down syndrome, such as dementia and malignancy.

Transient myeloproliferative disorder and GATA1 mutation in neonates with and without Down syndrome

OBJECTIVE

To report clinical experiences and cytogenetic findings of transient myeloproliferative disorder (TMD) in neonates with and without Down syndrome (DS).

METHODS

GATA1 gene was screened in DNA samples from neonates presenting with TMD during their leukemic and remission status.

RESULTS

Six neonates (2 phenotypically normal and 4 DS) born in the past 6 years had presented with TMD; all had trisomy 21 during leukemic status. Two DS infants died during early infancy, one of hepatic failure and one of cardiac complication. One non-DS infant evolved into myelodysplastic syndrome (MDS) and acute leukemia since 14 months old. Three other patients have not developed true leukemia after follow-up of 8, 9, and 70 months, respectively. The authors detected mutations within exon 2 of GATA1 gene in 3 DS and 2 non-DS infants. All these mutations disappeared after remission of TMD, but an identical mutation was detected in one non-DS patient when evolving into MDS. Trisomy 21 was confined to leukemic clone in non-DS patients.

CONCLUSIONS

TMD should be considered in case of congenital leukemia with megakaryoblastic features and accompanied by trisomy 21 and GATA1 mutation. Both DS and non-DS patients will possibly develop true leukemia within few years.

Transient myeloproliferative disorder in neonates with and without Down syndrome: a tale of 2 syndromes

Transient myeloproliferative disorder (TMD) in newborns with Down syndrome (DS) has been well described. We report 4 newborns, 2 with DS and 2 without DS, who developed TMD. One newborn with DS developed multiorgan failure and died despite treatment with low-dose cytarabine. In 3 newborns, the TMD resolved spontaneously. Two of these patients, 1 with and 1 without DS developed leukemia on subsequent follow-up and were treated successfully. We reviewed the clinical and laboratory data on 14 non-DS infants with TMD reported in the literature. According to limited data, these patients are more likely to develop leukemia than DS patients, however their outcome is better.

The key role of stem cell factor/KIT signaling in the proliferation of blast cells from Down syndrome-related leukemia

Transient leukemia (TL) has been observed in approximately 10% of newborn infants with Down syndrome (DS). Although treatment with cytarabine is effective in high-risk TL cases, approximately 20% of severe patients still suffer early death. In this study, we demonstrate abundant KIT expression in all 13 patients with GATA1 mutations, although no significant difference in expression levels was observed between TL and acute myeloid leukemia. Stem cell factor (SCF) stimulated the proliferation of the TL cells from five patients and treatment with the tyrosine kinase inhibitor imatinib suppressed the proliferation effectively in vitro. To investigate the signal cascade, we established the first SCF-dependent, DS-related acute megakaryoblastic leukemia cell line, KPAM1. Withdrawal of SCF or treatment with imatinib induced apoptosis of KPAM1 cells. SCF activated the RAS/MAPK and PI3K/AKT pathways, followed by downregulation of the pro-apoptotic factor BIM and upregulation of the anti-apoptotic factor MCL1. Although we found novel missense mutations of KIT in 2 of 14 TL patients, neither mutation led to KIT activation and neither reduced the cytotoxic effects of imatinib. These results suggest the essential role of SCF/KIT signaling in the proliferation of DS-related leukemia and the possibility of therapeutic benefits of imatinib for TL patients.

Transient myeloproliferative disorder and eosinophilic pericardial effusion in a down syndrome neonate

Transient myeloproliferative disorder seen in neonates with Down syndrome is often thought to have a benign course. The authors describe the clinical and laboratory profile of a neonate with Down phenotype and transient myeloproliferative disorder with pericardial effusion as co-morbidity. Pericardial fluid analysis showed eosinophils. Pericardial effusion resolved with prednisolone therapy. Regression in hepatosplenomegaly with clearance of blasts was seen by third week of illness. The clinical course suggested a benign infiltration of the pericardium. Presence of eosinophils supports the differentiating capability of the blast cells in transient myeloproliferative disorders.

Treatment and prognostic impact of transient leukemia in neonates with Down syndrome

Approximately 10% of the neonates with Down syndrome (DS) exhibit a unique transient leukemia (TL). Though TL resolves spontaneously in most patients, early death and development of myeloid leukemia (ML-DS) may occur. Prognostic factors as well as treatment indication are currently uncertain. To resolve that issue, we prospectively collected clinical, biologic, and treatment data of 146 patients with TL. The 5-year overall survival (OS) and event-free survival (EFS) were 85% plus or minus 3% and 63% plus or minus 4%, respectively. Multivariate analysis revealed a correlation between high white blood cell (WBC) count, ascites, preterm delivery, bleeding diatheses, failure of spontaneous remission, and the occurrence of early death. Treatment with cytarabine (0.5-1.5 mg/kg) was administered to 28 patients with high WBC count, thrombocytopenia, or liver dysfunction. The therapy had a beneficial effect on the outcome of those children with risk factors for early death (5-year EFS, 52% +/- 12% vs 28% +/- 11% [no treatment]; P = .02). Multivariate analysis demonstrated its favorable prognostic impact. A total of 29 (23%) patients with TL subsequently developed ML-DS. Patients with ML-DS with a history of TL had a significantly better 5-year EFS (91% +/- 5%) than those without documented TL (70% +/- 4%), primarily due to a lower relapse rate. A history of TL may therefore define a lower-risk ML-DS subgroup. This study was registered at www.clinicaltrials.gov as no. NCT 00111345.

Down syndrome: caring holistically in primary health care

All primary health care should be underpinned with a firm theoretical knowledge. The holistic management of Down syndrome patients should be an integral part of this knowledge base. The application of this knowledge should ideally encompass a positive approach to empowering patients to lead healthy, active and normal lives. This article highlights a basic documentation of what 'Down syndrome' is. The article gives community nursing staff the opportunity to refresh their knowledge of the condition, then encourages critical reflection on professional practice within primary care, with the intention of raising skill and awareness for the holistic management of patients with Down syndrome.

Incidence and clinical implications of GATA1 mutations in newborns with Down syndrome

Somatic mutations in the GATA1 gene are present in almost all cases of Down syndrome (DS)–associated acute megakaryoblastic leukemia (AMKL) and transient leukemia (TL). An in utero origin of the GATA1 mutation suggests it is an early leukemogenic event. To determine the detectable incidence and clinical relevance of GATA1 mutations in DS newborns, we screened Guthrie cards from 590 DS infants for mutations in the GATA1 gene. Twenty-two (3.8%) of 585 evaluable infants harbored a predicted functional GATA1 mutation; 2 were identified exclusively within intron 1. Hispanic newborns were 2.6 times more likely to have a mutated GATA1 gene than non-Hispanics (P = .02). Two newborns with a GATA1 mutation subsequently developed AMKL, and none of the infants without a functional GATA1 mutation were reported to have developed leukemia. In addition to screening for TL, a GATA1 mutation at birth might serve as a biomarker for an increased risk of DS-related AMKL.

Remarkable leukemogenic potency and quality of a constitutively active neurotrophin receptor, ΔTrkA

Neurotrophins and their receptors play a key role in neurogenesis and survival. However, we and others have recently obtained evidence for a potential involvement of this receptor system in leukemia. To investigate mechanisms underlying the leukemogenic potential of activated neurotrophin receptor signaling, we analyzed in vivo leukemogenesis mediated by deltaTrkA, a mutant of TRKA (tropomyosin-related kinase A) isolated from a patient with acute myeloid leukemia (AML). Retroviral expression of deltaTrkA in myeloid 32D cells induced AML in syngeneic C3H/Hej mice (n=11/11, latency approximately 4 weeks). C57Bl/6J mice transplanted with deltaTrkA-transduced primary lineage negative (Lin-) bone marrow cells died of a transient polyclonal AML (n=7/15, latency of <12 days). Serial transplantation of AML cells did not re-induce this disease but rather acute lymphoblastic leukemia (ALL, latency >78 days). All primary recipients surviving the early AML developed clonal ALL or myeloid leukemia (latency >72 days) that required additional genetic lesions. PI3K and mTOR-raptor were identified as the crucial mediators of leukemic transformation, whereas STAT and MAP kinase signaling pathways were not activated. Thus, our findings reveal potent and unique transforming properties of altered neurotrophin receptor signaling in leukemogenesis, and encourage further analyses of neurotrophin receptors and downstream signaling events in hematological malignancies.

Transient myeloproliferative disorder associated with trisomy 21

Transient myeloproliferative disorder (TMD) is a spontaneously resolving condition affecting infants born with trisomy 21 syndrome. Although TMD is rather rare among infants with trisomy 21, its ramifications can become severe enough that neonatal nurses should be aware of the condition, its manifestations, and its management. The spectrum of TMD presentation ranges from subtle blastemia in an otherwise healthy infant to severe, life-threatening expression of the disease. TMD may be a precursor to congenital leukemia—thus, the importance of nurses’ becoming aware of this condition. This article addresses the pathology of TMD, case reports in the literature, potential complications of the disorder, and nursing implications. A case study of an infant with dermatologic manifestations of TMD is presented, including history, differential diagnoses, treatment, and follow-up.

Prenatal sonographic findings and hematological abnormalities in fetuses with transient abnormal myelopoiesis with Down syndrome

OBJECTIVES

To determine relevant prenatal findings of transient abnormal myelopoiesis (TAM) that have important prognostic implications.

METHODS

The prenatal and postnatal medical records of all cases with confirmed TAM associated with Down syndrome were reviewed retrospectively, with emphasis on prenatal sonographic findings, fetal blood analysis, neonatal outcomes, and causes of death.

RESULTS

From January 1992 to December 2005, seven cases were confirmed postnatally as having TAM associated with Down syndrome. Sonography demonstrated hydrops with hepatomegaly in four, and isolated hepatomegaly in two of these seven cases. There were no findings suggestive of cardiac failure in cases of hydrops. Fetal blood analysis revealed elevated liver enzyme levels in six cases and hypoalbuminemia in four cases. Comparison of sonographic findings with fetal blood findings demonstrated an association between hydrops and hypoalbuminemia. Four of the seven cases were fatal. All fatal cases were associated with hydrops and the main cause of death was coagulopathy due to liver failure, which may have resulted from infiltration of the liver by blast cells.

CONCLUSIONS

Fetal TAM is associated with hepatomegaly and elevated liver enzyme levels. The prenatal finding with prognostic implications is hydrops, which may result from hypoalbuminemia due to liver failure.

Hematological abnormalities during the first week of life among neonates with Down syndrome: Data from a multihospital healthcare system

Various hematological abnormalities have been reported among neonates with Down syndrome. Thrombocytosis, thrombocytopenia, polycythemia, neutrophilia, transient myeloproliferative disorder (TMD), and congenital leukemia have all been reported. The two largest case series previously reported involved 63 and 31 cases. To acquire hematological data from a larger case series, we obtained all CBCs done during the first week after birth on all neonates with Down syndrome cared for in an Intermountain Healthcare (IHC) hospital with a date of birth between January 1, 2001 and December 31, 2005. During this period, 145,522 live births were recorded at 18 hospitals. Down syndrome was recognized in 226 (1 in 644). One hundred fifty-eight (70%) of these had one or more CBCs obtained before the seventh day (144 hr). Neonates who did versus did not have a CBC in the first week had a similar gestational age, birth weight, percentage who were LGA and SGA, and length of stay. Neutrophilia was the most common hematological abnormality detected, with 80% of absolute neutrophil counts above the upper limit of normal for age. Six percent (9/158) had blasts identified on the blood film and three, where this was persistent, were referred to the pediatric hematology service for further evaluation. The next most commonly detected abnormality was thrombocytopenia, with 66% of platelet counts <150,000/microl, and with 6% of counts <50,000/microl. The mean platelet volume did not correlate with the platelet count, but tended to run slightly large (9.2 +/- 1.3 fl), with 24% of values above 10 fl. Only one had a platelet transfusion. Polycythemia was the next most common hematological abnormality detected, with 33% of hematocrit values above 65% or hemoglobin concentrations above 22 g/dl. Six had a reduction transfusion. One patient had significant anemia (hematocrit <15%) and received an erythrocyte transfusion. One had neutropenia associated with an infection after bowel surgery. Neutrophilia, thrombocytopenia, and polycythemia were the most common hematological abnormalities observed among neonates with Down syndrome. Anemia, thrombocytosis, and neutropenia were not more common than among neonates who do not have Down syndrome. Hematological abnormalities were so common in this group that it seems reasonable to recommend that one or more CBCs be obtained on all neonates with Down syndrome.

Clinical manifestations of hematologic and oncologic disorders in patients with Down syndrome

Hematologic abnormalities are common in individuals with Down syndrome (DS). Increased erythrocyte mean corpuscular volume (MCV) is frequently found among DS infants and remains elevated throughout life in two-thirds of patients, making interpretation of red cell indices for diagnosis of nutritional anemias or bone marrow failure disorders more challenging. Transient myeloproliferative disorder (TMD) associated with pancytopenia, hepatosplenomegaly, and circulating immature WBCs, is found almost exclusively in DS infants with an incidence of approximately 10%. In most cases, TMD regresses spontaneously within the first 3 months of life, but in some children, it can be life threatening or even fatal. Despite the high rate of spontaneous regression, TMD can be a preleukemic disorder in 20-30% of children with DS. The types of malignancy, response to therapy, and clinical outcome in children with DS are also unique. There is an increased risk of leukemia with an equal incidence of lymphoid and myeloid leukemia. Acute megakaryocytic leukemia (AMKL) subtype is the most common form of acute myeloid leukemia (AML) in this setting, and is uncommon in children without DS. Somatic mutations of the gene encoding the hematopoetic growth factor GATA1 have been shown to be specific for TMD and AMKL in children with DS. Myelodysplastic syndrome can precede AML. Children with DS and leukemia are more sensitive to some chemotherapeutic agents such as methotrexate than other children which requires careful monitoring for toxicity. Although the risk for leukemia is higher in individuals with DS, these patients have a lower risk of developing solid tumors, with the exception of germ cell tumors, and perhaps retinoblastoma and lymphoma.

Transient leukemia (transient myeloproliferative disorder, transient abnormal myelopoiesis) of Down syndrome

Transient leukemia of Down syndrome (DS-TL), also known as transient myeloproliferative disorder of Down syndrome (DS) and transient abnormal myelopoiesis of DS, occurs in approximately 10% of DS neonates and in phenotypically normal neonates with trisomy 21 mosaicism. In DS-TL, peripheral blood analysis shows variable numbers of blasts and, usually, thrombocytopenia; other cytopenias are uncommon. Bone marrow characteristics of DS-TL are, likewise, variable, though (in contrast to other leukemias) the bone marrow blast differential can be lower than the peripheral blood blast differential. The blasts of DS-TL typically show light microscopic, ultrastructural, and flow cytometric evidence of megakaryocyte differentiation. DS-TL neonates have a approximately 15% risk of developing potentially fatal liver disease and show <10% incidence of hydrops fetalis. Additional manifestations of DS-TL include cutaneous involvement, hyperviscosity, myelofibrosis, cardiopulmonary failure, splenomegaly, and spleen necrosis. Despite its typical transient nature, 20% to 30% of DS-TL patients develop overt (nontransient) acute leukemia, usually within 3 years and typically of the M7 phenotype (acute megakaryoblastic leukemia). The pathogenesis of DS-TL (and of subsequent acute leukemia) involves mutation of GATA1 (on chromosome X), which normally encodes a transcription factor integral to normal development of erythroid, megakaryocytic, and basophilic/mast cell lines. The pathogenetic role of trisomy 21 in DS-TL is unclear. Though indications for chemotherapy in DS-TL have not been firmly established, the blasts of DS-TL are sensitive to low-dose cytosine arabinoside.

WT1 gene expression in children with Down syndrome and transient myeloproliferative disorder

Transient myeloproliferative disorder (TMD) is found in 10% of newborns with Down syndrome (DS). Myeloid leukemia develops in 25% within the following 3 years. Little is known about markers predicting leukemia occurrence. We studied expression levels of the Wilms tumor gene (WT1) by real-time quantitative PCR (RQ-PCR) in peripheral blood of five infants with TMD. WT1 levels were elevated similar to findings in AML. Longitudinal studies showed normalization of the WT1 level in all patients except one who developed GATA1 mutated myeloid leukemia at 11 months of age. The lack of normalization of WT1 level may be a predictor of leukemia development and WT1 expression may be an attractive marker for monitoring of minimal residual disease.

A prospective study of the natural history of transient leukemia (TL) in neonates with Down syndrome (DS): Children's Oncology Group (COG) study POG-9481

A unique transient leukemia (TL) has been described in newborns with Down syndrome (DS; or trisomy 21 mosaics). This leukemia has a high incidence of spontaneous remission; however, early death and subsequent development of acute megakaryoblastic leukemia (AMKL) have been reported. We prospectively evaluated 48 infants with DS and TL to determine the natural history and biologic characteristics of this disease, identify the clinical characteristics associated with early death or subsequent leukemia, and assess the incidence of subsequent leukemia. Blast cells associated with TL in DS infants exhibited FAB M(7) morphology and phenotype. Most infants (74%) had trisomy 21 (or mosaicism) as the only cytogenetic abnormality in the blast cells. Most children were able to spontaneously clear peripheral blasts (89%), normalize blood counts (74%), and maintain a complete remission (64%). Early death occurred in 17% of infants and was significantly correlated with higher white blood cell count at diagnosis (P < .001), increased bilirubin and liver enzymes (P < .005), and a failure to normalize the blood count (P = .001). Recurrence of leukemia occurred in 19% of infants at a mean of 20 months. Development of leukemia was significantly correlated with karyotypic abnormalities in addition to trisomy 21 (P = .037). Ongoing collaborative clinical studies are needed to determine the optimal role of chemotherapy for infants at risk for increased mortality or disease recurrence and to further the knowledge of the unique biologic features of this TL.

Congenital leukemia cutis with subsequent development of leukemia

We describe a newborn infant who was born with a purpuric rash and subcutaneous nodules. Skin biopsies demonstrated acute myeloid leukemia. Cytogenetic studies revealed an 11q23 rearrangement. Initial bone marrow and cerebrospinal fluid examination did not demonstrate medullary or meningeal disease. Chemotherapy was initiated on the basis of the abnormal cytogenetic findings in the skin biopsy. Intensive chemotherapy was, given but the infant's leukemia progressed. The patient died of refractory leukemia and secondary fungal disease. This case report supports the observation that leukemia cutis with an 11q23 rearrangement should be treated aggressively.

Optimizing therapy for myeloid disorders of Down syndrome

Children with Down syndrome (DS) are at increased risk of leukaemia. Myeloid disorders include transient abnormal myelopoiesis (TAM), myelodysplasia (MDS) and acute myeloid leukaemia (AML). Mutations in the GATA-1 gene, which encodes for a transcription factor central to the normal development of the erythroid and megakaryocytic lineages, are found in cases of TAM, MDS and AML in DS children. DS children with MDS/AML mostly present between the ages of 1 and 4 years, and have a large predominance of megakaryoblastic disease (French-American-British type M7). The MDS and AML are part of a single disease entity (myeloid leukaemia of Down syndrome) that is extremely sensitive to chemotherapy. Resistant disease and relapse are rare, but treatment-related toxicity is high, and deaths in remission have exceeded those due to disease in most series. Accordingly, controlled dosage reduction is the focus of contemporary treatment studies.

Hematopoietic stem cell transplantation for de novo acute megakaryocytic leukemia in first complete remission: a retrospective study of the European Group for Blood and Marrow Transplantation (EBMT)

Acute megakaryoblastic leukemia (M7 AML) is a highly aggressive disease. We evaluated outcomes in 57 children (11 with Down syndrome) and 69 adults with M7 AML after first complete remission (CR1) following autologous or HLA-identical allogeneic transplantation. Characteristics of the recipients of autologous transplants (38 children, 37 adults) were, respectively: median age, 1.7 and 46 years; non-total body irradiation (non-TBI) conditioning regimen, 97% and 70%; bone marrow as stem cell source, 74% and 43%. Characteristics of the recipients of allogeneic transplants (19 children, 32 adults) were, respectively: median age, 2.8 and 37 years; non-TBI regimen, 63% and 42%; bone marrow as stem cell source, 95% and 69%. Autologous transplantation benefited children more; the relapse rate was high in adults. Results for autologous transplantation were (children and adults, respectively): engraftment, 90% and 100%; 3-year treatment-related mortality (TRM) rate, 3% and 8%; relapse rate, 45% and 64%; leukemia-free survival (LFS) rate, 52% and 27%; overall survival (OS) rate, 61% and 30%. After allogeneic transplantation, TRM was fairly low in children and adults, and relapse rates were lower than after autologous transplantation. Results for allogeneic transplantation were, respectively: engraftment, 95% and 90%; TRM, 0% and 26%; relapse rate, 34% and 28%; LFS, 66% and 46%; OS, 82% and 43%). We conclude that M7 AML patients in CR1 (except children with Down syndrome, who already have better outcomes) can benefit from transplantation. (Blood. 2005;105:405-409)

Transient neonatal myeloproliferative disorder without Down syndrome and detection of GATA1 mutation

Transient myeloproliferative disorder is a form of self-limited leukemia that occurs almost exclusively in neonates with Down syndrome. The authors report an unusual case of a newborn without constitutional trisomy 21 who developed undifferentiated leukemia and subsequently achieved clinical and molecular remission without chemotherapy. Cytogenetics and molecular analysis have shown trisomy 21 and GATA1 mutation restricted to leukemic cells. G-to-T transversion was detected, which is predicted to result in a premature stop codon (c.119G>T; pGlu67X) in diagnosis samples. These findings emphasize that there must be a powerful interaction between GATA1 and trisomy 21 in leukemogenesis process.