Ewing sarcoma is an uncommon bone malignancy of childhood. Although Ewing sarcoma is mostly a tumor of bone, it may also arise from soft tissues (extraskeletal Ewing sarcoma). We report a case of extraskeletal Ewing sarcoma that arose in the retroperitoneum of a 18-month-old girl and presented with right leg pain and gait disturbance. A brief review of related literatures was also made.
Female ; Gait ; Humans ; Infant ; Leg ; Sarcoma, Ewing*

Extrarenal Wilms' tumor is an extremely rare solid tumor in childhood. The most common location is the retroperitoneum or inguinal area. The diagnosis should be made by histologic confirmation of Wilms' tumor of extrarenal origin and by excluding the existence of supernumerary kidney or embryogenic tumor with teratomatous components. We report a 4 year-old boy with retroperitoneal extrarenal Wilms' tumor, considered to be the second case reported in Korea, who has been relapse-free for 26 months after the completion of chemotherapy. We also made a brief review of the literatures.
Child, Preschool ; Diagnosis ; Drug Therapy ; Humans ; Kidney ; Korea ; Male ; Wilms Tumor*

Extramedullary relapse of childhood acute lymphoblastic leukemia (ALL) occurs most commonly in the central nervous system or in the testes. Isolated relapse on chest wall as a soft tissue mass is extremely rare in children with ALL. We experenced a 12-year-old girl who developed an isolated relapse on chest wall during the treatment for ALL. She had a pain and protruding mass on right anterior chest wall 6 months after the initial diagnosis of ALL. Imaging study revealed an 5 7 cm sized soft tissue mass on the right chest wall. Histopathologic examination revealed infiltrates composed of immature lymphoblasts with morphology identical with that of previous bone marrow aspiration. Studies on bone marrow and cerebrospinal fluid were negative for disease at this time. The patient was treated with 3,000 cGy of local irradiation in 10 fractions and systemic chemotherapy with ifosfamide and etoposide. The mass size decreased markedly, but she has been suffering from development of multiple mass in other site and recurrent pleural effusion.
Bone Marrow ; Central Nervous System ; Cerebrospinal Fluid ; Child ; Diagnosis ; Drug Therapy ; Etoposide ; Female ; Humans ; Ifosfamide ; Pleural Effusion ; Precursor Cell Lymphoblastic Leukemia-Lymphoma* ; Recurrence* ; Testis ; Thoracic Wall* ; Thorax*

PURPOSE: Unlike murine oncoretroviruses which can infect only dividing cells, lentiviral vector based on HIV have been shown to efficiently transfer genetic materials into a various cells which makes lentiviral-based vector systems promising candidates for clinical gene therapy, but have also raised safety concerns because of potential creation of replication-competent lentivirus (RCL) by uncontrolled recombination. In this study, I intended to validate RT-PCR assay for detection of replication-competent virus (RCV) in vector preparations using HIV vector based gene delivery system. METHODS: We prepared a replication-competent lentiviral supernatant from a 293T cell line which had been transfected with plasmid pHIV-VSV G-IRES-eYFP as a positive control, by introducing VSV-G into a first-generation HIV-based vector. A variant of this virus, which has additional deletions of vif and vpr was also used as another positive control. As a negative control, VSV-G pseudotyped HIV-based vector encoding YFP was used. These viruses encode enhanced yellow fluorescent protein (eYFP). I used reverse transcriptase (RT)-PCR to detect VSV-G RNA sequences contained within viral supernatants produced from transiently transfected 293T cells using oligonucleotides specific for conserved for VSV-G element. RESULTS: After production in 293T cells, titer of each virus were<107 IU/mL. eYFP expression in 293T cells increased according to passage with extremely fluorescent with replication-competent vector. Correctly-sized DNA products was always detected, even when using supernatants from cells separately transfected with VSV-G and replication-defective HIV. CONCLUSION: These data suggested that RT-PCR based method is not appropriate for transient transfection of producers where cell lysis is routine. Instead we turned our attention to the development of other sensitive assays.
Base Sequence ; Cell Line ; DNA ; Gene Transfer Techniques* ; Genetic Therapy ; HIV* ; Lentivirus* ; Oligonucleotides ; Plasmids ; Recombination, Genetic ; RNA-Directed DNA Polymerase ; Transfection

PURPOSE: For separation of RBC from cord blood, it is important to minimize RBC contamination without significant loss of nucleated cells using sedimentation agent that is safe for human use. This study was performed to investigate the possibility of replacing 6% hydroxyethylstarch (HES) with 10% pentastarch (PS) which is a lower molecular weight hetastarch-analog that is cleared from the circulation rapidly. METHODS: After dilution of cord blood till hematocrit 25%, PS or HES were added by the ratio of 7:1 and 5:1 respectively. Sedimentation was performed for 2 hours by gravity. RESULTS: PS was used in 14 cases with volume of 72.4+/-22.3 mL (45~126 mL) and HES in 8 cases with volume of 58.4+/-8.0 mL (50~70 mL). Sedimentation rate has reached at plateau by 90 minutes in PS group and it was slightly faster than in HES group. Recovery rate of nucleated cells and residual RBC were 82.9+/-10.7%, 7.6+/-5.4% in PS group, and 84.0+/-4.7%, 10.7+/-2.3% in HES group. There were no significant differences between the two groups (P=0.657, 0.219). Cell viabilities were high in both groups; 92+/-3% before separation and 97+/-2% in PS group and 98+/-3% in HES group. CD34+ cells were 0.75+/-0.28% before separation and 0.64+/-0.21% in PS group and 0.60+/-0.30% in HES group (P=0.690). CFU-GM after 2 week culture were 27.4+/-20.0 per 1 105 mononuclear cells in PS group and 22.9+/-8.6 in HES group (P=0.856). CONCLUSION: These results demonstrated that PS has similar efficacy to HES for separation of RBC from umbilical cord blood. Considering its rapid clearance and faster sedimentation rate, PS can replace HES for RBC separation in cord blood banking.
Cell Survival ; Fetal Blood* ; Granulocyte-Macrophage Progenitor Cells ; Gravitation ; Hematocrit ; Humans ; Hydroxyethyl Starch Derivatives* ; Molecular Weight

PURPOSE: Multidrug resistance (MDR) is one of the main obstacles in the successful anticancer chemotherapy. Classic MDR phenotype is characterized by overexpression of membrane bound permeability-glycoprotein (Pgp) drug-efflux pump, encoded by MDR1 gene. The non-Pgp MDR phenotype is caused by overexpression of multidrug resistance associated protein (MRP), another membrane transport protein, encoded by MRP gene. We examined the mRNA expression of MDR1 and MRP genes in various types of pediatric malignant solid tumors at diagnosis. METHODS: Five fresh frozen tissue and 15 primarily cultured cell samples from 20 children diagnosed as malignant solid tumors (8 neuroblastomas, 5 medulloblastomas, 3 Burkitt lymphomas, 2 Wilms tumors, 1 each of rhabdomyosarcoma and rhabdoid tumor) were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Among 20 pediatric solid tumors, MDR1 mRNA expression was observed in 14 cases (70%), and MRP mRNA expression was observed in 15 cases (75%). The co-expression of MDR1 and MRP was recognized in 12 (60%) of 20 cases. Event (death or relapse) occurred in 7 cases during observation period of median 9 months after diagnosis, and 6 of these 7 cases (86%) showed the co-expression of MDR1 and MRP. CONCLUSION: These data suggest that MRP, like MDR1, may have an important negative impact on the outcome of chemotherapy in pediatric malignant solid tumors, and it is possible that these two genes may collaborate in causing the appearance of MDR under certain circumstances.
Burkitt Lymphoma ; Cells, Cultured ; Child ; Diagnosis ; Drug Resistance, Multiple* ; Drug Therapy ; Humans ; Medulloblastoma ; Membranes ; Multidrug Resistance-Associated Proteins* ; Neuroblastoma ; Phenotype ; Rhabdomyosarcoma ; RNA, Messenger ; Wilms Tumor

PURPOSE: Multidrug resistance in the treatment of cancer mediated by several drug resistant genes impedes the successful management of cancer. The authors investigated the expression of drug resistant genes, including multidrug resistance (mdr1), multidrug resistance-associated protein (mrp), topoisomerase IIalpha (Topo IIalpha), and topoisomerase IIbeta (Topo IIbeta) in patients with childhood acute lymphoblastic leukemia (ALL; n=24) and in normal controls (n=6). METHODS: The levels of their transcripts in the bone marrow mononuclear cells were compared by semiquantitative RT-PCR, comparing the optical density ratio of PCR products of target genes to that of beta2-microglobulin. RESULTS: The expression of all 4 genes were detected in ALL patients as well as in normal controls except for Topo IIalpha, which were not detected in controls. The expression levels of mdr1, mrp and Topo IIbeta in ALL patients were significantly higher than those of normal controls [(2.1+/-2.2 vs 0.9+/-0.3, P> 0.024), (0.5+/-0.2 vs 0.2+/-0.1, P=0.016), and (0.7+/-0.2 vs 0.3+/-0.1, P=0.016)], respectively. The expression level of mdr1 gene transcript was relatively higher than those of mrp and Topo IIbeta. However, there was no correlation between the expression of multidrug resistant genes and survival and/or relapse of ALL. CONCLUSION: Though multidrug resistance genes did not serve as an independent prognostic factor, they might be used for markers for disease progression or relapse in childhood ALL. A longitudinal study of those genes is necessary to elucidate the prognostic significance in childhood ALL.
Bone Marrow ; Disease Progression ; DNA Topoisomerases, Type II ; Drug Resistance, Multiple* ; Genes, MDR* ; Humans ; Multidrug Resistance-Associated Proteins ; Polymerase Chain Reaction ; Precursor Cell Lymphoblastic Leukemia-Lymphoma* ; Recurrence

PURPOSE: An increasing number of immunocompromised patients are contracting opportunistic infections caused by Aspergillus, resulting in a significant morbidity and mortality. We reviewed the clinical presentation, radiologic characteristics, histopathologic findings, treatment strategies, and outcome of invasive aspergillosis (IA) in immunocompromised children. METHODS: Thirteen children having IA were retrospectively analyzed. RESULTS: Acute myelogenous leukemia (n=9, 69.2%) was the most common underlying disease, followed by acute lymphocytic leukemia (n=2), Fanconi anemia (n=1), and chronic granulomatous disease (CGD, n=1). Pulmonary involvement was present in 12 patients (92.3%). The sinuses or nose were involved in 4 (30.8%). The patient with CGD had lung, soft tissue, and bone involvement. Central nervous system, gastrointestinal, heart involvement were not documented. Histology or culture proven IA were found in 6 patients (46.2%). In pulmonary IA, typical findings of thoracic computed tomography, such as halo sign or air-crescent sign, was observed in 6 patients. Amphotericin B was given to all patients along with itraconazole (69.2%), G- or GM-CSF (84.6%). AmBisome was subsequently substituted for Amphotericin in 4. One patient with pulmonary mycetoma underwent lobectomy. Seven patients (53.8%) were improved by antifungal measures, but no patients achieved a long term survival. IA was implicated as a cause of death in 7 (4 with massive pulmonary hemorrhage). Most of the rest succumbed to the relapse of underlying leukemia. CONCLUSION: IA remains a formidable infection in immunocompromised children despite current treatment. Lung was the most common site of infection and massive pulmonary hemorrhage might ensue. Early diagnosis and development of effective measures, including surgery, are warranted.
Amphotericin B ; Aspergillosis* ; Aspergillus ; Cause of Death ; Central Nervous System ; Child* ; Early Diagnosis ; Fanconi Anemia ; Granulocyte-Macrophage Colony-Stimulating Factor ; Granulomatous Disease, Chronic ; Heart ; Hemorrhage ; Humans ; Immunocompromised Host ; Itraconazole ; Leukemia ; Leukemia, Myeloid, Acute ; Lung ; Mortality ; Mycetoma ; Nose ; Opportunistic Infections ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Recurrence ; Retrospective Studies

PURPOSE: The use of granulocyte transfusion (GT) which had been diminished since 1980s has been recently interested on the base of clinical efficacy approved by transfusion of granulocyte collected after administration of granulocyte-colony stimulating factor (G-CSF) to donors. So we studied the clinical efficacy of GT in severe neutropenic pediatric patients with severe infections. METHODS: Twelve patients with malignant hematologic disorders and solid tumors in Ajou University Hospital from March 1997 to February 2001 were indicated for GT. These patients had continuous neutropenia-related infections despite appropriate antibiotics, antifungal or IV immunoglobulin therapy. GTs were carried out 12 hrs after collection of granulocytes using leukapheresis from donors stimulated by G-CSF. RESULTS: The median number of GT is 3 (2~7), and the mean dose of granulocyte is 3.51+/-4.21 10(10)/m(2) and mean volume of granulocyte is 220 +/-22.92 mL. The median duration of the use of G-CSF and antibiotics or antifungal agents is 6 (3~14) days and 3 (1~9) days. Ten of 12 patients had favorable responses (FR), and 2 patients had unfavorable responses (UR). Two patients who had FR died of acute respiratory distress syndrome (ARDS), complication of GT. CONCLUSION: GT is effective treatment for severe neutropenic pediatric patients with severe infections. Enough amount of granulocytes could be collected after administration of G-CSF without dexamethasone to donors. However, ARDS which is an adverse effect of GT, is considered in pulmonary compromised patients.
Anti-Bacterial Agents ; Antifungal Agents ; Dexamethasone ; Granulocyte Colony-Stimulating Factor ; Granulocytes* ; Humans ; Immunization, Passive ; Leukapheresis ; Neutropenia ; Respiratory Distress Syndrome, Adult ; Tissue Donors

PURPOSE: We compared the clinical outcomes of allogeneic bone marrow transplantation (BM), peripheral blood stem cell transplantation (PB) and cord blood stem cell transplantation (CB) in children with malignant and non-malignant diseases. METHODS: We retrospectively analysed the engraftment speed, episodes of infection, acute graft versus host disease (GVHD), and survival rate in 27 children who underwent hematopoietic stem cell transplantation (HSCT) at Dong-A Cancer Center from August 1998 to July 2001. RESULTS: HSCT were done with BM in 16 patients, CB in 6 and PB in 5. The neutrophil and platelet engraftment were achieved at 13.27+/-4.10, 24.58+/-9.41 days in BM, 12.00+/-1.09, 15.88+/-4.42 days in PB, and 39.00+/-15.68, 76.50+/-37.01 days in CB (P=0.001, P=0.001). There were 17 episodes of bacteremia and 10 episodes of viral infections without any significant differences between stem cell sources. There were 8 cases (7 in BM, 1 in CB) of acute GVHD, 4 cases (2 in BM, 2 in CB) of graft failure and 3 cases of relapse (1 in BM, 2 in CB) after HSCT. The duration of median follow-up was 14.34+/-8.32 months in BM, 11.43+/-10.03 months in PB, and 16.56+/-13.76 months in CB. The overall and event free survival rate were 81.5% and 63.0%, respectively. CONCLUSION: There were no significant differences in episodes of infection between the types of HSCT. Although there were HLA mismatched donors for CB, the incidence of acute GVHD was lower, and graft failure or relapse rate was higher than BM.
Bacteremia ; Blood Platelets ; Bone Marrow Transplantation ; Child* ; Cord Blood Stem Cell Transplantation ; Disease-Free Survival ; Follow-Up Studies ; Graft vs Host Disease ; Hematologic Diseases* ; Hematopoietic Stem Cell Transplantation* ; Hematopoietic Stem Cells* ; Humans ; Incidence ; Neutrophils ; Peripheral Blood Stem Cell Transplantation ; Recurrence ; Retrospective Studies ; Stem Cells* ; Survival Rate ; Tissue Donors ; Transplants