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

Using the in vitro drug sensitivity test to identify candidate treatments for transient abnormal myelopoiesis

Approximately 20% of patients with transient abnormal myelopoiesis (TAM) die due to hepatic or multiorgan failure. To identify potential new treatments for TAM, we performed in vitro drug sensitivity testing (DST) using the peripheral blood samples of eight patients with TAM. DST screened 41 agents for cytotoxic properties against TAM blasts. Compared with the reference samples of healthy subjects, TAM blasts were more sensitive to glucocorticoids, the mitogen-activated protein kinase kinase (MAP2K) inhibitor trametinib, and cytarabine. Our present results support the therapeutic potential of glucocorticoids and the role of the RAS/MAP2K signalling pathway in TAM pathogenesis.

Spinal epidural granulocytic sarcoma in a child precedent to clinical manifestation of acute myeloid lymphoma: case report

A 13-year-old boy presented with an epidural thoracic granulocytic sarcoma manifesting as rapidly progressive paraplegia preceding clinical manifestation of acute myeloid leukemia (AML). Magnetic resonance imaging revealed a thoracic epidural tumor. He underwent emergent laminectomy and the tumor was totally resected. The initial histological diagnosis was malignant lymphoma. The correct diagnosis of epidural granulocytic sarcoma and AML was established based on cell-surface markers and a chromosomal study of the bone marrow cells. A combination of chemotherapy and bone marrow transfusion achieved complete remission of leukemia. No evidence of AML has emerged over the 18-month follow-up period. Granulocytic sarcoma should be considered in the differential diagnosis of an epidural mass in pediatric patients with or without acute leukemia. Immediate diagnosis and appropriate treatment are recommended to prevent leukemic transformation.

Comparison of megadose methylprednisolone versus conventional dose prednisolone in hematologic disorders

Glucocorticoids (GCs) are known for their clinically useful effects in immunologic and inflammatory disorders. Although there is a huge volume of knowledge concerning the cellular and molecular effects of GCs, statements regarding their effects in multiple diseases at variable doses are not clear-cut owing to pharmacogenetic differences. The main actions of GCs in hematologic disorders have been related to their differentiation-inducing and apoptosis-inducing effects, but modification of several steps of the hematopoietic and/or immune pathway has also been reported. In our clinic, mega-dose methylprednisolone (MDMP) has been successfully used for treatment of different hematologic diseases, such as leukemias, bone marrow failure in aplastic anemia, hypoplastic anemia, myelodysplastic syndrome, neutropenia, autoimmune diseases, and in some congenital hereditary diseases. Both clinical and experimental studies in our department revealed that MDMP was more effective than conventional dose steroids. It is interesting that MDMP can be curative in some congenital hereditary diseases such as Diamond-Blackfan syndrome. However, more research is required to clarify their roles in biology, physiology, and molecular genetics.

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.

Acute myeloid leukemia presenting as spinal cord compression

We report the findings of a 10-year-old boy who presented to a pediatric emergency department with symptoms of spinal cord compression. Radiological imaging demonstrated multiple soft tissue masses in the head and spine. The surgical pathology showed that the masses were comprised of myeloid leukemia cells. These findings were consistent with those observed on bone marrow aspiration. The characteristics and management of extramedullary leukemia are discussed.

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.

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.