A novel approach to treatment in childhood acute myeloblastic leukemia and myelodysplastic syndrome with high-dose methylprednisolone as a differentiation- and apoptosis-inducing agent of myeloid leukemic cells.

Differentiation-inducing therapy with all-trans retinoic acid significantly improved the outcome in children with acute promyelocytic leukemia (APL). Therefore, use of agents that induce differentiation of leukemic cells in non-APL children appears to be a highly promising therapeutic approach. Based on the experimental studies in mice, we have shown that short-course high-dose methylprednisolone (HDMP) treatment can induce terminal differentiation of leukemic cells in children with various subtypes of acute myeloblastic leukemia (AML-M1,-M2,-M3,-M4,-M7). It has also been shown to induce apoptosis of myeloid leukemic cells with or without differentiation. Administration of HDMP as a single agent resulted in a rapid clinical improvement, a marked decrease in blast cells in both peripheral blood and bone marrow and dramatic decreases in the size of extramedullary leukemic mass in children with AML and myelodysplastic syndrome (MDS). Addition of HDMP to cytotoxic chemotherapy regimens increased the remission rate and improved the outcome in these children. Future clinical trials with HDMP would contribute to further improvements in the treatment results in these children.

The role of splenectomy in children with juvenile myelomonocytic leukemia.

Splenectomy has been performed as a palliative treatment both in adults and children with myelodysplastic syndrome (MDS). However, there is no report describing the course after splenectomy in children with MDS. The aim of this study was to evaluate the impact of splenectomy on the outcome of six children with juvenile myelomonocytic leukemia (JMML) who had no HLA identical donor and who became unresponsive to chemotherapy. Persistent thrombocytopenia, increased erythrocyte transfusion requirement and massive splenomegaly were the indications for splenectomy. Hemoglobin values and platelet counts improved following splenectomy in five out of the six patients. Erythrocyte transfusion requirements decreased and none of the patients who responded received erythrocyte transfusion for at least six months. More importantly, the quality of life improved markedly. No mortality related to splenectomy was observed. In conclusion, splenectomy may be considered as a safe supportive treatment approach for some children with JMML.

Natural history and early diagnosis of LAD-1/variant syndrome.

The syndrome of leukocyte adhesion deficiency (LAD) combined with a severe Glanzmann-type bleeding disorder has been recognized as a separate disease entity. The variability in clinical and cell biological terms has remained largely unclear. We present data on 9 cases from 7 unrelated families, with 3 patients being actively followed for more than 12 years. The disease entity, designated LAD-1/variant syndrome, presents early in life and consists of nonpussing infections from bacterial and fungal origin, as well as a severe bleeding tendency. This is compatible with 2 major blood cell types contributing to the clinical symptoms (ie, granulocytes and platelets). In granulocytes of the patients, we found adhesion and chemotaxis defects, as well as a defect in NADPH oxidase activity triggered by unopsonized zymosan. This last test can be used as a screening test for the syndrome. Many proteins and genes involved in adhesion and signaling, including small GTPases such as Rap1 and Rap2 as well as the major Rap activity-regulating molecules, were normally present. Moreover, Rap1 activation was intact in patients' blood cells. Defining the primary defect awaits genetic linkage analysis, which may be greatly helped by a more precise understanding and awareness of the disease combined with the early identification of affected patients.

The effect of steroid on myeloid leukemic cells: the potential of short-course high-dose methylprednisolone treatment in inducing differentiation, apoptosis and in stimulating myelopoiesis.

Several in vitro studies have shown that dexamethasone (Dex) and prednisolone can induce differentiation of some mouse and human myeloid leukemic cells to macrophages and granulocytes. Based on in vitro experiments, we have shown that short-course (3-7 days) high-dose methylprednisolone (HDMP) (20-30 mg/kg/day) treatment can induce differentiation of myeloid leukemic cells in vivo in children with different subtypes of acute myeloblastic leukemia (AML) (AML-M1, -M2, -M3, -M4, -M7). We have also shown that induction of apoptosis of myeloid leukemic cells with or without differentiation is possible by short-course HDMP treatment. In addition, short-course HDMP treatment has been shown to be effective in accelerating leukocyte recovery, possibly stimulating normal CD34-positive hematopoietic progenitor cells. Addition of HDMP to mild cytotoxic chemotherapy (low-dose cytosine arabinoside (LD-Ara-c), weekly mitoxantrone and Ara-c or 6-thioguanine) increased the remission rate (87-89%) and improved the outcome of AML children. We believe that the results of our 17-year clinical experience will provide important benefits to AML patients.

Myeloprotective effect of short-course high-dose methylprednisolone treatment before consolidation therapy in children with acute myeloblastic leukemia.

In our previous studies, short-course high-dose methylprednisolone (HDMP) has been shown to shorten the chemotherapy-induced neutropenic period by stimulating the CD34(+) hematopoietic progenitor cells in children with acute leukemia. In this study, we investigate the role of short-course HDMP on induction of a myeloprotective effect when administered before consolidation therapy consisting of high-dose cytosine arabinoside and daunorubicin. Thirty-four consecutive newly diagnosed children with acute myeloblastic leukemia (AML) who received 64 courses of consolidation regimen were entered into the study. The patients received HDMP (group A) at a daily dose of 30 mg/kg methylprednisolone starting 4 days before the initiation of consolidation therapy. The control group did not receive HDMP (group B). There were no differences in the white blood cell (WBC) and absolute neutrophil counts (ANC) between group A (at day -4) and group B (at day 0) at the beginning of the study (medians: 3 x 10(9)/L vs. 3.2 x 10(9)/L and 1.5 x 10(9)/L vs. 1.7 x 10(9)/L, respectively). The WBC count increased significantly from 3 x 10(9)/L to 6.4 x 10(9)/L, and ANC increased from 1.5 x 10(9)/L to 3.9 x 10(9)/L after 4 days of HDMP treatment in group A (P < 0.01). Following high-dose chemotherapy, the median values of WBC and ANC also remained higher than the control values during the 16 days of the follow-up period. The neutropenic period was significantly shorter in the HDMP group than in the control group (9 +/- 5.2 days vs. 22 +/- 4.7 days) (P < 0.05). The duration of hospitalization and the interval between two chemotherapy cycles were significantly decreased in group A when compared group B (9 +/- 2.7 vs. 14 +/- 2.7 days; 22 +/- 4.7 vs. 26 +/- 4.2 days, respectively) (P < 0.05). Moreover, following consolidation therapy, the number of patients with ANC values below 0.5 x 10(9)/L was lower in group A when compared the group B. In conclusion, the administration of short-course (4 days) HDMP before high-dose chemotherapy has been found to be beneficial for reducing the duration and severity of neutropenia. Further studies with short-course HDMP are required to evaluate its myeloprotective effects in patients with other malignancies.

Genital ulcers after treatment with all-trans-retinoic acid in a child with acute promyelocytic leukemia.

All-trans-retinoic acid (ATRA) has been shown to improve the outcome of patients with acute promyelocytic leukemia (APL). However, various adverse effects of ATRA treatment have been noted, such as scrotal and genital ulcers in adult patients. The authors report genital ulcers that developed in a child with APL after ATRA treatment. An 8-year-old girl with APL was treated with ATRA for 21 days and after discontinuation of ATRA treatment she developed genital ulcers. Systemic and local antibiotic pomades were applied and the lesions improved within 15 days. In conclusion, genital ulcers may develop in children with APL as a complication of ATRA treatment and physicians should be alert to this possibility.

Long-term survival in severe combined immune deficiency: the role of persistent maternal engraftment.

Two siblings with severe combined immune deficiency, one with maternal engraftment and detectable immunologic functions who was alive at the age of 8 years are presented. Both patients had the same JAK3 gene mutation, suggesting that maternal engraftment may result in immune competence leading to long-term survival in patients with severe combined immune deficiency.

Acute lymphoblastic leukemia in infants.

Between January 1978 and August 1999, 29 infants with newly diagnosed acute lymphoblastic leukemia (ALL) were treated on three consecutive protocols. Eighteen patients with infant ALL diagnosed between 1978-1991 were included in Group 1. In this group, treatment comprised a two- or three-drug induction with prednisolone, vincristine and L-asparaginase, and maintenance therapy consisted of weekly oral administration of mercaptopurine and methotrexate for three years. Group 2: Between 1991 and 1999, 11 infants with ALL were treated by St. Jude Total Therapy XI (n=4) and XIII (n=7) protocols with minor modification. Three years' event-free survival (+/-SE) was 14 +/- 9% in group 1. In group 2, this rate was 25 +/- 22% in Total XI and 57 +/- 19% in Total XIII. Outcome for infants on protocols Total Therapy XI and XIII improved compared with that of group 1.

Children with acute myeloblastic leukemia presenting with extramedullary infiltration: the effects of high-dose steroid treatment.

To evaluate whether children with acute myeloblastic leukemia (AML) presenting with extramedullary infiltration (EMI) have different clinical, morphologic features and prognosis from children without EMI, a 127 consecutive previously untreated children with AML were entered in this study. Fifty-one children (40%) had EMI at diagnosis and 27% of these showed multiple site involvement. Twenty-seven of 127 children (21%) presented myeloid tumors. No age related differences in the incidence of EMI was noted. However, analysis of clinical and biological features at diagnosis showed that WBC count > or =50 x 10(9) l(-1), hepatosplenomegaly >5 cm, FAB AML-M4 and AML-M5 subtypes and CD13, CD14 expression of bone marrow (BM) leukemic cells (>20%) were more frequent in children with EMI. Two consecutive treatment protocols were used. In both protocols remission was achieved with combined high-dose methylprednisolone (HDMP) as a differentiating and apoptosis inducing agent with mild cytotoxic chemotherapy (low-dose cytosine arabinoside (LD Ara-C), weekly mitoxantrone and Ara-C or 6-thioguanine). Administration of short-course (4-7 days) HDMP (20-30 mg/kg per day) alone resulted in a remarkable decrease in peripheral blood, BM blasts and in the size of EMI in responding patients. In both protocols, remission rate in patients with EMI was 71 and 80%, which was lower than that of the patients without EMI (87 and 89%). This may be attributed to the higher frequency of unfavorable features in children with EMI. However, in patients who presented with myeloblastoma and treated with a more intensive post-remission therapy (AML-94), the 4-year disease-free survival (DFS) and event-free survival (EFS) rates were not found to be significantly different from children who had no EMI (P>0.05). Whereas, the outcome of children who presented with gingival infiltration did not improve. In further studies, the prognostic significance of different localisation of EMI and the effect of addition of HDMP to cytotoxic chemotherapy should be explored in larger series.

The potential effect of short-course high-dose steroid on the maturation and apoptosis of leukemic cells in a child with acute megakaryoblastic leukemia.

High-dose methylprednisolone (HDMP) treatment has been shown to induce differentiation of myeloid leukemic cells in children with acute promyelocytic leukemia and other subtypes (FAB AML M1-M2-M4) of acute myeloblastic leukemia. In the present study, a child with acute megakaryoblastic leukemia (AMKL) was given HDMP (30 mg/kg/day) orally in a single dose for the first 4 days of induction therapy. A marked decrease in peripheral blood blast cells and an increase in platelet count associated with a striking change in bone marrow (BM) morphology was observed following a short-course of HDMP treatment alone. BM cells developed distinct morphology characterized by cytoplasmic blebbing and some appeared as platelet producing micromegakaryocytes. Flow cytometric analysis of the BM cells 4 days after HDMP treatment demonstrated a decrease in the percentage of cells co-expressing CD34 and CD117 antigens and a marked increase in CD42a antigen. These changes in BM morphology and immunophenotype may suggest maturation effect of HDMP on megakaryocytic leukemic cells. In addition ultrastructural analysis of BM cells cultured with methylprednisolone (10(-3) and 10(-6) M) for 24 and 48 h showed numerous apoptotic cells. This was coincident with a significant increase in the percentage of annexin positive cells. These results suggest that HDMP treatment may induce differentiation and apoptosis of leukemic cells in a child with AMKL and it could be a promising agent for remission induction of patients with AMKL.

Characterization of MTHFR, GSTM1, GSTT1, GSTP1, and CYP1A1 genotypes in childhood acute leukemia.

The role of methylenetetrahydrofolate reductase (MTHFR C677T), glutathione S-transferases (GSTM1 and GSTT1 null, GSTP1 Ile105Val), and cytochromes p450 (CYP1A1*2A) genotypes in the etiology of childhood leukemia was simultaneously investigated. 144 Turkish children with acute lymphoblastic leukemia (ALL) and 33 with acute nonlymphoblastic leukemia (ANLL) were studied and compared with 185 healthy pediatric controls. The frequency of MTHFR genotype was insignificantly higher in ALL (7.7%) and ANLL (6.3%) than in controls (4.4%). Equal distribution of the GSTM1 null genotype was detected between ALL patients and controls (55%), while its incidence was slightly higher in ANLL patients (61.3%). Although GSTT1 null genotype was insignificantly lower in ALL patients (20.9%) than controls (22.7%), it was significantly underrepresented in ANLL patients (6.5%) (P = 0.05, OR 0.24, 95% CI 0.05-1.03). The homozygous frequency of GSTP1 genotype did not differ significantly between groups of ALL (3.7%), ANLL patients (9.1%) and controls (4.9%). Homozygous CYP1A1*2A genotype was underrepresented in ALL patients (1%) as compared to control (4.8%) but the differences did not reach to statistical significance (OR 0.21; 95% CI 0.03-1.72). Homozygosity for this genotype was not detected in ANLL patients. No particular association was noted between different combinations of combined genotypes and risk of development of childhood ALL and ANLL. These results suggested that there are no significant associations between the studied genotypes and the risk of developing either form of acute leukemia except GSTT1 null and homozygosity for CYP1A1 genotypes that may play protective roles in the development of ANLL in Turkish children.

The role of short course of high-dose methylprednisolone in children with acute myeloblastic leukemia (FAB M2) presented with myeloid tumor.

The authors have previously demonstrated a favorable effect of high-dose methylprednisolone (HDMP), which can induce differentiation and apoptosis of leukemic cells in children with acute myeloblastic leukemia (AML). Here, they evaluate the effect of short-course HDMP in 2 children with acute myeloblastic leukemia (AML-M2) presented with myeloid tumor (MT). Methylprednisolone (20 or 30 mg/kg/day) was given orally, in a single dose, without using other antileukemic agents. Rapid cytoreduction in MT, peripheral blood, and bone marrow blasts was observed in both children following short-course (4 or 7 days) HDMP treatment, possibly due to HDMP-induced differentiation and apoptosis of leukemic cells. The effects of HDMP should be explored in patients with other subtypes of AML who present with MT.

The effect of short-course high-dose methylprednisolone on peripheral blood lymphocyte subsets in children with acute leukemia during remission induction treatment.

We have previously demonstrated a favorable effect of high-dose steroid in the treatment of children with acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML). This study was performed to determine the effect of short-course high-dose methylprednisolone (HDMP) treatment on the peripheral blood (PB) T lymphocyte subsets, and blast cells, during remission induction treatment in 23 children with newly diagnosed acute leukemia (16 with ALL, seven with AML). All patients were administered HDMP as a single daily oral dose of 30mg/kg for the first 4 days of induction therapy. The number of PB lymphocyte subsets (CD3, CD4, CD8, CD16+56, CD45RA, and CD45RO) were determined by flow cytometry before and after 4 days of HDMP treatment. While the number of PB blast cells significantly decreased, the absolute number of T lymphocytes expressing CD3, CD4, CD8, CD45RA and the absolute number of CD16+56 (natural killer) cells increased in all patients. We suggest that the beneficial effects of HDMP in the induction treatment of acute leukemia may occur partly due to an increase in the number of PB T lymphocyte subsets. A study randomly assigning patients to treatment with either conventional therapy or HDMP may provide further information.

The effect of short-course high-dose methylprednisolone on peripheral blood CD34+ progenitor cells of children with acute leukemia during remission induction therapy.

This study was undertaken to determine the effect of short-course high-dose methylprednisolone (HDMP) treatment on peripheral blood (PB) CD34+ progenitor cells during remission induction treatment in 11 children with newly diagnosed acute leukemia (7 with ALL, 4 with AML) whose bone marrow (BM) cells expressed fewer than 5% CD34 at the time of diagnosis. All children who had no infection were given HDMP as a single daily oral dose of 30 mg/kg for the first four days of induction therapy. The number of CD34+ progenitor cells were determined by flow cytometry before and after four days of HDMP treatment. While the number of PB blast cells significantly decreased after only a four-day course of HDMP treatment, the number of PB CD34+ progenitor cells increased in all patients. In addition, after four days of HDMP treatment polymorphonuclear leukocytes (PMN) and mononuclear cells (MNC) increased significantly (p < 0.05). We suggest that the potential beneficial effects of HDMP in the induction treatment of acute leukemia may occur partly by the stimulation of PB CD34+ hematopoietic progenitor cells in a short period of time.