Adaptor molecules expression in normal lymphopoiesis and in childhood leukemia.

Transmembrane adaptor proteins are key mediators of antigen receptor signaling in lymphocytes. By influencing proliferation and differentiation, these molecules might play a role in ethiopathogenesis of acute lymphoblastic leukemia (ALL). The aim of this study was to characterize expression of PAG, LAT, NTAL and LIME adaptors at the mRNA and protein levels in normal B- and T-precursors.

Quantification of fusion transcript reveals a subgroup with distinct biological properties and predicts relapse in BCR/ABL-positive ALL: implications for residual disease monitoring.

Minimal residual disease (MRD) monitoring is an essential tool for risk group stratification in current treatment protocols for childhood acute lymphoblastic leukaemia (ALL). Although quantitative detection of clonal immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangements is currently considered to be the standard method, leukaemia fusion genes provide other possible targets for MRD follow-up, as already demonstrated in TEL/AML1-positive ALLs. We analysed and compared MRD levels quantified by BCR/ABL transcript detection and by the standard Ig/TCR-based method in 218 bone marrow specimens from 17 children with BCR/ABL-positive ALL.

Pharmacokinetics of high-dose methotrexate in infants treated for acute lymphoblastic leukemia.

Background: Interfant-99 was an international collaborative treatment protocol for infants with acute lymphoblastic leukemia (ALL).

Procedure: We collected data on 103 infants at the time of their first treatment with high-dose methotrexate (HD MTX), 5 g/m(2). Children <6 months of age received two-third of the calculated dose based on body surface area (BSA), children 6-12 months three-fourth of the calculated dose, and children >12 months full dose.

Prevalence of HHV-6 integrated chromosomally among children treated for acute lymphoblastic or myeloid leukemia in the Czech Republic.

Chromosomal integration of human herpesvirus 6 (HHV-6) is a novel situation found in a small percentage of individuals. While active HHV-6 infection is treatable using antivirals, the abnormally high level of HHV-6 DNA found in chromosomal integration of HHV-6 (CI-HHV-6) is not affected by such drugs. Stored DNA samples taken originally for detection of fusion genes and minimal residual disease from 339 pediatric patients treated for leukemia in the Czech Republic between the years 1995-2007 were tested retrospectively.

Kinetics of dendritic cells reconstitution and costimulatory molecules expression after myeloablative allogeneic haematopoetic stem cell transplantation: implications for the development of acute graft-versus host disease.

Allogeneic hematopoetic stem cell transplantation (HSCT) represents a unique opportunity to monitor the kinetics of reconstitution of dendritic cells (DCs) and their dynamics in distinct pathologies. We analyzed DCs reconstitution after myeloablative HSCT. We separately analyzed patients with acute GVHD.

Cytomegalovirus encephalitis/retinitis in allogeneic haematopoietic stem cell transplant recipient treated successfully with combination of cidofovir and foscarnet.

We report an 18-yr-old female patient with repeated CMV reactivations after HSCT treated by several pre-emptive courses of virostatic therapy. Seven months after HSCT, she developed CMV encephalitis/retinitis. Initial therapy with GCV and hyperimmune globulin failed, and later on GCV-resistant strain was detected.

Allo-SCT in children with high-risk leukemia using unmanipulated grafts from alternative donors.

Allogeneic HSCT is a curative treatment for high-risk leukemia. In Europe, approximately 15% of children have an HLA-matched sibling, but in 65-70% HLA allele-matched (9-10/10) unrelated donors (UD) can be identified. Transplantation using an HLA partially mismatched donor, unrelated cord blood or haploidentical family donor with graft manipulation is then considered with preference on the basis of local experience and/or availability.

Covert preleukemia driven by MLL gene fusion.

Acute leukemia is considered to be a two- or multiple-step process. Although there is a considerable knowledge regarding the character of the "first hit," the nature of the "second hit" remains unanswered in most of the cases including leukemias with MLL gene rearrangement. We demonstrate here a striking sequence of events, which include a covert, protracted preleukemic phase characterized by a dominant MLL/FOXO3A clone with intact myeloid differentiation and the subsequent acquisition of a secondary genetic abnormality, leading to overt lymphoblastic leukemia.

[Therapy of acute promyelocytic leukemia in Czechia: results and analysis of prognostic factors].

We have retrospectively evaluated a cohort of 144 patients (including 17 pediatric ones) with de novo acute promyelocytic leukemia registered in databases of institutions cooperating within the CELL group (The Czech Leukemia Study Group for Life). The patients were diagnosed according to WHO criteria from 1989 until 2006. The aim was to check how well fared the patients, the majority of whom was not included into clinical trials, in real life.

Haematopoietic stem cell transplantation in children in eastern European countries 1985-2004: development, recent activity and role of the EBMT/ESH Outreach Programme.

The paediatric population of 19 eastern European countries amounts to approximately 80 million children. Between 1985 and 2004, the number of centres performing haematopoietic stem cell transplantation (HSCT) in children increased from 1 in 1985 to 24 in 2004 and the yearly number of paediatric HSCTs rose from 1 in 1985 to 291 in 2004. Altogether, 2342 transplants were reported to the EBMT Registry during this time (Poland 953, Czech Republic 501, Hungary 269, Russia 217, Croatia 129, Slovakia 71, Bulgaria 45, Serbia and Montenegro 36, Slovenia 35, Belarus 33, Estonia 26, Lithuania 19 and Romania 8).

Successful therapy with ABLC, surgery and posaconazole for Rhizopus microsporus var. rhizopodiformis liver eumycetoma in a child with acute leukaemia.

Invasive fungal infection negatively influences the morbidity and mortality in heavily immuno-incompetent patients. Diagnosis of non-Aspergillus mould infections remains challenging despite application of a wide spectrum of non-culture-based microbiological techniques. Invasive diagnostic procedures are often essential.

B-cell reconstitution after allogeneic SCT impairs minimal residual disease monitoring in children with ALL.

Minimal residual disease (MRD) detection using quantification of clone-specific Ig or TCR rearrangements before and after transplantation in children with high-risk ALL is an important predictor of outcome. The method and guidelines for its interpretation are very precise to avoid both false-negative and -positive results. In a group of 21 patients following transplantation, we observed detectable MRD positivities in Ig/TCR-based real-time quantitative PCR (RQ-PCR) leading to no further progression of the disease (11 of 100 (11%) total samples).

Eligibility for allogeneic transplantation in very high risk childhood acute lymphoblastic leukemia: the impact of the waiting time.

The advantage of allogeneic transplant from compatible related donors versus chemotherapy in children with very-high-risk acute lymphoblastic leukemia in first complete remission was previously demonstrated in an international prospective trial. This study quantified the impact of time elapsed in first remission in the same cohort. Of 357 pediatric patients with very-high-risk acute lymphoblastic leukemia, 259 received chemotherapy, 55 transplantation from compatible related and 43 from unrelated donors.

T-cell receptor Vbeta CDR3 oligoclonality frequently occurs in childhood refractory cytopenia (MDS-RC) and severe aplastic anemia.

(Very) severe acquired aplastic anemia ((v)SAA) and myelodysplastic syndrome (MDS) are rare diseases in childhood. (V)SAA is a bone marrow (BM) failure syndrome characterized by immune-mediated destruction of hematopoietic progenitors. MDS is a malignant clonal stem cell disorder, of which the hypoplastic variant is, in case of absence of a cytogenetic clone, difficult to separate from (v)SAA.

Minimal residual disease (MRD) analysis in the non-MRD-based ALL IC-BFM 2002 protocol for childhood ALL: is it possible to avoid MRD testing?

The ALL IC-BFM 2002 protocol was created as an alternative to the MRD-based AIEOP-BFM ALL 2000 study, to integrate early response criteria into risk-group stratification in countries not performing routine PCR-based MRD testing. ALL IC stratification comprises the response to prednisone, bone marrow (BM) morphology at days 15 and 33, age, WBC and BCR/ABL or MLL/AF4 presence. Here, we compared this stratification to the MRD-based criteria using MRD evaluation in 163 patients from four ALL IC member countries at days 8, 15 and 33 and week 12.

Allogeneic stem cell transplantation in children with leukemia using human leukocyte antigen-mismatched unrelated donors.

Allogeneic HSCT is a curative treatment, when chemotherapy fails, for certain malignant diseases. In Europe, only 15% of the indicated children have an HLA-matched sibling available; in 65-70% of others, HLA allele-matched (9-10/10) UDs can be identified. For the rest, it is necessary to identify other alternative donors (HLA-mismatched family or unrelated cord blood).

A treatment protocol for infants younger than 1 year with acute lymphoblastic leukaemia (Interfant-99): an observational study and a multicentre randomised trial.

Background: Acute lymphoblastic leukaemia in infants younger than 1 year is rare, and infants with the disease have worse outcomes than do older children. We initiated an international study to investigate the effects of a new hybrid treatment protocol with elements designed to treat both acute lymphoblastic leukaemia and acute myeloid leukaemia, and to identify any prognostic factors for outcome in infants. We also did a randomised trial to establish the value of a late intensification course.

Unrelated partially matched lymphocyte infusions in a patient with complete DiGeorge/CHARGE syndrome.

We present an infant with cDGS overlapping with CHARGE syndrome, who suffered from T-cell deficiency treated with screened healthy DLI from an unrelated donor (8/10 match). The first dose of DLI (1.1 x 10(6) CD3+/kg) was administered at the age of six months, the second one (0.

Childhood secondary ALL after ALL treatment.

Data on secondary acute lymphoblastic leukaemia (sALL) following ALL treatment are very rare. However, the incidence might be underestimated as sALLs without a significant lineage shift might automatically be diagnosed as relapses. Examination of immunoglobulin and T-cell receptor gene rearrangements brought a new tool that can help in discrimination between relapse and sALL.

Langerhans cell histiocytosis of vulva in adolescent.

Langerhans cell histiocytosis (LCH) affecting child vulva alone is a very rare disease. Only 13 cases of primary vulvar LCH have been previously reported in the medical literature. We describe an additional case in which the LCH was confined to the vulva, with review of the literature.