Acute myelogenous leukemia in Down's syndrome: report of a single pediatric institution using a BFM treatment strategy

Clonal Myeloproliferative Disorders in Patients with Down Syndrome-Treatment and Outcome Results from an Institution in Argentina

Children with Down syndrome (DS) are at an increased risk of developing clonal myeloproliferative disorders. The balance between treatment intensity and treatment-related toxicity has not yet been defined. We analyzed this population to identify risk factors and optimal treatment. This single-center retrospective study included 78 DS patients <16 years-old with Transient Abnormal Myelopoiesis (TAM, n = 25), Acute Myeloblastic Leukemia (DS-AML, n = 41) of which 35 had classical Myeloid Leukemia associated with DS (ML-DS) with megakaryoblastic immunophenotype (AMKL) and 6 sporadic DS-AML (non-AMKL). Patients with DS-AML were treated according to four BFM-based protocols. Classical ML-DS vs. non-DS-AMKL were compared and the outcome of ML-DS was analyzed according to treatment intensity. Only four patients with TAM required cytoreduction with a 5-year Event-Free Survival probability (EFSp) of 74.4 (±9.1)%. DS-AML treatment-related deaths were due to infections, with a 5-year EFSp of 60.6 (±8.2)%. Megakaryoblastic immunophenotype was the strongest good-prognostic factor in univariate and multivariate analysis (p = 0.000). When compared ML-DS with non-DS-AMKL, a better outcome was associated with a lower relapse rate (p = 0.0002). Analysis of administered treatment was done on 32/33 ML-DS patients who achieved CR according to receiving or not high-dose ARA-C block (HDARA-C), and no difference in 5-year EFSp was observed (p = 0.172). TAM rarely required treatment and when severe manifestations occurred, early intervention was effective. DS-AML good outcome was associated with AMKL with a low relapse-rate. Even if treatment-related mortality is still high, our data do not support the omission of HDARA-C in ML-DS since we observed a trend to detect a higher relapse rate in the arm without HDARA-C.

Infectious Complications in Children With Acute Myeloid Leukemia and Down Syndrome: Analysis of the Prospective Multicenter Trial AML-BFM 2004

BACKGROUND

Children with acute myeloid leukemia (AML) and Down syndrome have high survival rates with intensity-reduced chemotherapeutic regimens, although the optimal balance between dose intensity and treatment toxicity has not been determined. We, therefore, characterized infectious complications in children with AML and Down syndrome treated according to AML-BFM 2004 study (ClinicalTrials.gov NCT00111345; amended 2006 for Down syndrome with reduced intensity).

PROCEDURE

Data on infectious complications were gathered from the medical records in the hospital where the patient was treated. Infectious complications were categorized as fever without identifiable source (FUO), or as microbiologically or clinically documented infections.

RESULTS

A total of 157 infections occurred in 61 patients (60.5% FUO, 9.6% and 29.9% clinically and microbiologically documented infections, respectively). Almost 90% of the pathogens isolated from the bloodstream were Gram-positive bacteria, and approximately half of them were viridans group streptococci. All seven microbiologically documented episodes of pneumonia were caused by viruses. Infection-related mortality was 4.9%, and all three patients died due to viral infection.

CONCLUSIONS

Our data demonstrate that a reduced-intensity chemotherapeutic regimen in children with AML and Down syndrome is still associated with high morbidity. Although no patient died due to bacteria or fungi, viruses were responsible for all lethal events. Future studies, therefore, have to focus on the impact of viruses on morbidity and mortality of patients with AML and Down syndrome.

Myeloid leukaemia in children with Down syndrome: report of the registry-based French experience between 1990 and 2003

AIM

To determine the epidemiology of myeloid leukaemia (ML) in children with Down syndrome (DS) and the efficacy of two approaches, low-dose cytarabine-based regimen (LDC) and standard-dose intensive chemotherapy (SD).

PROCEDURE

All children with Down syndrome aged from 2 months to 15 years with ML/myelodysplasia registered in the French registry between January 1990 and December 2003 were included.

RESULTS

Forty-four patients were included. The median age was 1.75 years. The French-America-British subtypes were as follows: M7: 24, M0: 6, M2: 5, M6: 2. Forty-three patients were treated with curative prospect, 20 patients with LDC regimen and 22 according to SD protocols, 1 was given the LDC regimen plus autologous stem-cell transplantation. The event-free survival (EFS) and overall survival (OS) at 5 years were 64.4% and 76.8%. At 5 years, OS in LDC and SD groups were 65% and 85.9% (P = 0.08). EFS were 45% and 80.3% respectively (P < 0.01).

CONCLUSION

Children with DS can adequately tolerate SD chemotherapy with a significant superiority of EFS relative to LDC. We suggest that higher levels of cure can be obtained in DS-ML with SD chemotherapy including cytarabine and anthracyclines.

Long-term results of an ultra low-dose cytarabine-based regimen for the treatment of acute megakaryoblastic leukaemia in children with Down syndrome

Children with acute megakaryoblastic leukaemia (AMKL) and Down syndrome (DS) show a favourable response to chemotherapy, probably due to increased sensitivity of the leukaemic blasts to cytarabine. In contrast, dose-intensive approaches have resulted in disproportionate treatment-related mortality in this group. The survival of children with AMKL and DS was retrospectively compared following treatment with a low-dose chemotherapy protocol, consisting of cytarabine (10 mg/m2/dose), retinylpalmitate and vincristine or standard chemotherapy. Event-free (67 +/- 11%) and overall survival (77 +/- 10%) at 5 years were not significantly different in both groups. Further reduction of treatment intensity in AMKL of children with DS, therefore, appears feasible.

The incidence peaks of the childhood acute leukemias reflect specific cytogenetic aberrations

The correlation between age and karyotype was studied in 1425, 0 to 14.9 years old children who were diagnosed with acute lymphoblastic leukemia (ALL) or acute myeloblastic leukemia. Almost 80% of the non-Down B-cell precursor ALL cases in the 2 to 7 years frequency peak group who had aberrant cytogenetic results had either a high-hyperdiploid clone (51 to 61 chromosomes) or a translocation t(12;21)(p13;q22). Among B-cell precursor ALL cases, high white blood cell counts correlated with earlier age at diagnosis (rS=-0.23; P<0.001) being most evident for 11q23/MLL-aberrations, translocation t(12;21)(p13;q22), and high-hyperdiploidy. Among acute myeloblastic leukemia patients, frequency peaks were found for those with MLL/11q23 rearrangements (peak: first year), Down syndrome (peak: second to third year), or cytogenetic abnormalities other than translocations t(8;21), t(15;17), and inv(16)/t(16;16) (peak: first to third year). The epidemiology of the cytogenetic subsets of acute leukemias questions whether age as a disease-related prognostic parameter has any relevance in childhood leukemia clinical research beyond being a surrogate marker for more important, truly biologic features such as cytogenetic aberrations and white cell count at diagnosis. Further research is needed to explore whether the 2 to 7 years age incidence peak in childhood ALL harbor yet unidentified cytogenetic subsets with the same natural history as the high-hyperdiploid and t(12;21)-positive leukemias.

Treatment for myeloid leukaemia of Down syndrome: population-based experience in the UK and results from the Medical Research Council AML 10 and AML 12 trials

Down syndrome (DS) children are at an increased risk of developing myelodysplasia and acute myeloid leukaemia (AML). We retrospectively analysed the population-based data on 81 children with myeloid leukaemia of Down syndrome (ML-DS) from the UK National Registry of Childhood Tumours and experience in the Medical Research Council (MRC) AML 10 and AML 12 trials, which enrolled 46 children with ML-DS from 1988 to 2002. Eight per cent of UK children with AML had DS, but DS children comprised only 5% of children registered in MRC trials. The unique clinical characteristics of ML-DS were confirmed. Overall survival (OS) of ML-DS at 5 years increased from 47% in UK children diagnosed from 1988 to 1995 to 75% in children diagnosed from 1996 to 2002. OS for DS children registered in AML 10 and AML 12 was 74% in 5 years and improved from AML 10 to AML 12 (56% vs. 83%) There was no significant difference in OS between DS and non-DS children (OS: 74% vs. 62%, P = 0.4) in the trials, but this result masked a significant increase in early death amongst DS children, with a significant reduction in mortality later on. Relapse was significantly reduced (3% vs. 39%, P = 0.0003), leading to the improved disease-free survival (83% vs. 56%, P = 0.02). Given the increased number of early treatment-related deaths, future treatment protocols should aim to reduce chemotherapy dosage or intensity whilst maintaining low rates of resistant and recurrent disease.

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.

AML patients with Down syndrome have a high cure rate with AML-BFM therapy with reduced dose intensity

Despite improved prognosis in acute myelogenous leukaemia (AML) children with Down syndrome (DS), therapy-related toxicity remained a problem. We compared 67 DS patients from study AML-BFM 98 with 51 DS patients of the previous study AML-BFM 93, and the non-DS groups of both studies. Compared to non-DS patients, DS patients were treated with reduced anthracycline doses, without high-dose cytarabine/mitoxantrone and without cranial irradiation. AML-DS patients were in median 1.8 years old, and 102/118 (86%) showed the typical morphology of acute megakaryoblastic leukaemia. In study 93, seven DS patients did not receive AML-specific chemotherapy, and treatment modifications were more common. Results improved significantly for patients treated in study 98 with a 3-year survival of 91+/-4 vs 70+/-7% in study 93 (P=0.001). There were no differences in outcome concerning the age groups 0-<or=2 and 2-<or=4 years (event-free survival for treated patients 0-<or=2 years 83+/-4%, 2-<or=4 years 81+/-7%). The cumulative incidence of relapses was significantly lower in DS (7+/-3%) than in non-DS patients (28+/-7%). Therapy-related toxicity was generally lower in DS patients treated according to study 98. We conclude that a standardised and dose-reduced treatment schedule including the main components of AML treatment is advisable for AML children with DS.

Acute leukaemia in children with Down syndrome: a population-based Nordic study

To determine the epidemiology and outcome of children with Down syndrome (DS) diagnosed with acute leukaemia in the Nordic countries, data registered in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) population-based leukaemia registry were analysed. Of 3494 children with acute leukaemia diagnosed between July 1984 and December 2001, 136 patients (3.9%) with DS were identified. 2.1% of the children with acute lymphoid leukaemia (ALL) and 14.0% of the children with acute myeloid leukaemia (AML) had DS. In ALL, DS patients had similar age and sex distribution and no major differences in blood counts compared with non-DS children. None of the DS patients had T cell leukaemia. Outcome was inferior to that of non-DS children and treatment results did not improve over time. In AML, DS patients showed a significant female predominance and all but one were <5 years old. DS patients with AML had significantly lower platelet and white blood cell counts and two-thirds were type M7 as according to the French-American-British classification. None of the patients <5 years of age had typical AML cytogenetic aberrations. Outcome was far better in the DS group. DS patients treated for AML after 1992 had an excellent outcome (probability of event-free survival, 83 +/- 6%). The high proportion of female DS patients with AML is unexplained. The differing treatment results in AML versus ALL need further evaluation and represent a challenge for the coming years.

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)

Down syndrome, drug metabolism and chromosome 21

It has been recognized that chromosomal abnormalities in childhood leukemia, are linked to both leukemogenesis and segregate patients into prognostic treatment groups. This is best exemplified in cases of children with Down syndrome (DS), who have significantly higher risks of developing leukemia compared to non-DS children and distinctive treatment outcomes, particularly in cases of acute myeloid leukemia (AML). The high event-free survival (EFS) rates of DS AML patients and in particular, patients with megakaryocytic leukemia (AMkL), at least in part reflects an increased sensitivity to cytosine arabinoside (ara-C) secondary to increased expression of the chromosome 21-localized gene, cystathionine-beta-synthase, and potentially global mechanisms which increase the susceptibility of cells to undergo apoptosis. Somatic mutations of the X-linked transcription factor gene, GATA1, have been detected uniformly and exclusively in DS AMkL cases, which may lead to altered expression of GATA1 target genes and alter the metabolism of drugs including ara-C. Hyperdiploid acute lymphoblastic leukemia (ALL) cells with extra copies of chromosome 21, generate higher levels of the active methotrexate (MTX) metabolite, MTX polyglutamates. This is on account of increased intracellular transport of MTX via the reduced folate carrier (RFC) whose gene is localized to chromosome 21 and may also account for the increased MTX-associated toxicity of DS ALL patients. Microarray technology should lead to the identification of additional gene targets linked to the treatment response of specific cytogenetic leukemia subgroups.

Fatal familial infantile myelofibrosis

Malignant megakaryopoiesis can cause chronic or acute myelofibrosis through production of fibrogenic cytokines. Chronic myelofibrosis is a clonal disorder with marrow fibrosis, myeloid metaplasia, gross splenomegaly, and teardrop cells. Acute myelofibrosis differs by its aggressiveness, by the fact that it is more common in children, and by lack of organomegaly or anisopoikilocytosis. Surprisingly, in early childhood and infancy, splenomegaly and teardrop red cells become an important feature. Infantile myelofibrosis is a rare disease, except in Down syndrome. Familial occurrence of infantile myelofibrosis is exceedingly rare. The author describes an unfortunate family whose four consecutive children died of a very fulminant form of acute myelofibrosis during their first year of life. The fulminant nature of the disease, the degree of splenomegaly, and the prominence of anisopoikilocytosis were even more marked than in currently reported cases of infantile myelofibrosis. The mode of inheritance remained illusive. With two female children, sex-linked inheritance was not possible. It could not have been inherited in an autosomal dominant fashion with normal parents and with two normal children from the father's second marriage. A new autosomal dominant mutation in the germ cell of either parent is another possibility. Autosomal recessive inheritance remained a logical explanation, although such a high degree of disease presentation in a non-consanguineous marriage seems to put that possibility in question.

Infectious complications in pediatric acute myeloid leukemia: analysis of the prospective multi-institutional clinical trial AML-BFM 93

Infections still remain a major cause of therapy-associated morbidity and mortality in children with acute myeloid leukemia (AML). To improve supportive care measurements, detailed information on frequency and characteristic features of infectious complications is needed. We retrospectively analyzed the medical charts of 304 children, treated in 30 hospitals according to the multi-institutional clinical trial AML-BFM 93. Overall, 855 infectious complications occurred in 304 patients (fever without identifiable source (n=523; 61.2%), clinically (n=57; 6.7%) and microbiologically documented infections (n=275; 32.1%)). Neutropenia was present in 74.1% of the infectious episodes. In all, 20 patients died of infection-associated complications (15/276 (5.4%) patients without and 5/28 (17.9%) with Down syndrome), most of them during early induction therapy (n=11). Blood stream infections occurred in 228 episodes (Gram-positive (n=202) and Gram-negative (n=42) pathogens). Invasive fungal infection was probable or proven in 15 patients. In 113 out of the 855 infectious episodes (13.3%), pneumonia was radiologically diagnosed. Better strategies of supportive care might help to improve overall survival in children undergoing chemotherapy for AML. Therefore, children with AML should be treated in specialized pediatric centers, and there should be a very low threshold to readmit patients, in particular patients with pulmonary symptoms.

Distinctive multidrug sensitivity and outcome of acute erythroblastic and megakaryoblastic leukemia in children with Down syndrome

We assessed the in vitro chemosensitivity of acute erythroblastic and megakaryoblastic leukemia cells from children with Down syndrome (DS) compared to non-DS children. We conducted in vitro tests using the MTT assay of bone marrow samples from 12 children with DS and 16 children without DS. Patients were newly diagnosed based on the morphology and expression of platelet-specific antigens. Induction failure occurred more frequently in the non-DS group (n = 4) than in the DS group (n = 0, P = .053). Children with DS had a superior event-free survival (EFS) probability of 0.750 at 4 years, compared to an EFS probability of 0.375 for non-DS children (P = .049). Blast cells from DS patients were significantly more sensitive to daunorubicin, melphalan, mitoxantrone, 4-hydroperoxy-cyclophosphamide, vincristine, etoposide, bleomycin, and pirarubicin than those from non-DS patients. Four of the 16 non-DS patients were found to have acquired an extra chromosome 21 in their leukemia cells: blasts from these patients also tended to have greater chemosensitivity than those from patients without an extra chromosome 21. Blast cells from DS patients are markedly sensitive to various drugs. These results suggest that the fragility of blast cells derived from DS patients may be related to an increased susceptibility to apoptosis.

Biology and outcome of childhood acute megakaryoblastic leukemia: a single institution's experience

To describe the clinical and biologic features of pediatric acute megakaryoblastic leukemia (AMKL) and to identify prognostic factors, experience at St Jude Children's Research Hospital was reviewed. Of 281 patients with acute myeloid leukemia treated over a 14-year period, 41 (14.6%) had a diagnosis of AMKL. Six patients had Down syndrome and AMKL, 6 had secondary AMKL, and 29 had de novo AMKL. The median age of the 22 boys and 19 girls was 23.9 months (range, 6.7-208.9 months). The rate of remission induction was 60.5%, with a 48% rate of subsequent relapse. Patients with Down syndrome had a significantly higher 2-year event-free survival (EFS) estimate (83%) than did other patients with de novo AMKL (14%) or with secondary AMKL (20%; P < or =.038). Among patients who had de novo AMKL without Down syndrome, 2-year EFS was significantly higher after allogeneic bone marrow transplantation (26%) than after chemotherapy alone (0%; P =.019) and significantly higher when performed during remission (46%) than when performed during persistent disease (0%; P =.019). The 5-year survival estimates were significantly lower for de novo AMKL (10%) than for other forms of de novo AML (42%; P <.001). Treatment outcome is very poor for patients with AMKL in the absence of Down syndrome. Remission induction is the most important prognostic factor. Allogeneic transplantation during remission offers the best chance of cure; in the absence of remission, transplantation offers no advantage over chemotherapy alone. (Blood. 2001;97:3727-3732)

Oral administration of cefixime to lower risk febrile neutropenic children with cancer

BACKGROUND

Febrile neutropenia is a heterogeneous condition. Recently, several risk factors have been defined, permitting the definition of a lower risk group of patients who may benefit form less aggressive therapy. The use of an oral antibiotic approach was tested in the current trial.

METHODS

From May 1997 to March 1998, 154 episodes of lower risk febrile neutropenia in 128 children with a mean age of 62 (range, 8-200) months were enrolled in this randomized, single-institution trial. Inclusion criteria were fever (> 38 degrees C), neutropenia (absolute neutrophil count < 500/mm(3)), lower risk features (i.e., absence of severe comorbidity factors, good clinical condition, negative blood cultures, control of local infection, no fever during the last 24 hours), and compliance of parents. After 3 days of ceftriaxone (100 mg/kg/day administered intravenously [i.v.]) every 12 hours plus amikacin (15 mg/kg/day i.v.) every 24 hours for 3 days, all patients were discharged and randomized to be allocated to 2 treatment arms. Group A (n = 74) received ceftriaxone cefixime (8 mg/kg/day administered orally) every 24 hours for 4 days, whereas Group B (n = 80) was treated with ceftriaxone plus amikacin for 7 days. Failure was defined as the need for second hospitalization during the same episode of neutropenia, or fever during the 7 days after discharge.

RESULTS

Most of the patients (49% in Group A and 55% in Group B) had acute leukemia. Fifty-four (72%) children in Group A and 46 (56%) in Group B had fever of unknown origin (P = not significant [NS]). No significant differences were found in the sites of initial infection between the two groups. Overall results were outstanding, with a favorable outcome in 73 of 78 cases (98.6%) in Group A and 78 of 80 cases (97.5%) in Group B (P = NS). Three patients needed a second hospitalization due to failure of the initial therapy: one in Group A and two in Group B. All three did well with secondary treatment.

CONCLUSIONS

In lower risk febrile neutropenic children receiving anticancer therapy, the efficacy of oral cefixime, given for 4 days after 72 hours of intravenous ceftriaxone plus amikacin, was similar to that of 7 days of parenteral ceftriaxone plus amikacin. The oral outpatient therapy approach to the treatment of lower risk febrile neutropenia after chemotherapy is safe and may be cost-saving. This strategy might be adopted as standard therapy in the future.