A nationwide phase II study of delayed local treatment for children with high-risk neuroblastoma: The Japan Children's Cancer Group Neuroblastoma Committee Trial JN-H-11.

PURPOSE: Survival rates of patients with high-risk neuroblastoma are unacceptable. A time-intensified treatment strategy with delayed local treatment to control systemic diseases has been developed in Japan. We conducted a nationwide, prospective, single-arm clinical trial with delayed local treatment. This study evaluated the safety and efficacy of delayed surgery to increase treatment intensity. PATIENTS AND METHODS: Seventy-five patients with high-risk neuroblastoma were enrolled in this study between May 2011 and September 2015. Delayed local treatment consisted of five courses of induction chemotherapy (cisplatin, pirarubicin, vincristine, and cyclophosphamide) and myeloablative high-dose chemotherapy (melphalan, etoposide, and carboplatin), followed by local tumor extirpation with surgery and irradiation. The primary endpoint was progression-free survival (PFS). The secondary endpoints were overall survival (OS), response rate, adverse events, and surgical complications. RESULTS: Seventy-five patients were enrolled, and 64 were evaluable (stage 3, n = 8; stage 4, n = 56). The estimated 3-year PFS and OS rates (95% confidence interval [CI]) were 44.4% [31.8%-56.3%] and 80.7% [68.5%-88.5%], resspectively. The response rate of INRC after completion of the treatment protocol was 66% (42/64; 95% CI: 53%-77%; 23 CR [complete response], 10 VGPR [very good partial response], and nine PR [partial response]). None of the patients died during the protocol treatment or within 30 days of completion. Grade 4 adverse effects, excluding hematological adverse effects, occurred in 48% of patients [31/64; 95% CI: 36%-61%]. Major Surgical complications were observed in 25% of patients [13/51; 95% CI: 14%-40%]. CONCLUSION: This study indicates that delayed local treatment is feasible and shows promising efficacy, suggesting that this treatment should be considered further in a comparative study of high-risk neuroblastoma.

Multimodal treatment including standard chemotherapy with vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide for the Ewing sarcoma family of tumors in Japan: Results of the Japan Ewing Sarcoma Study 04.

BACKGROUND: The survival rate in patients with Ewing sarcoma family of tumors (ESFT) in Japan was reported to be < 50% in the 1990s. The Japan Ewing Sarcoma Study Group was established to improve the prognosis of ESFT in Japan. The aim of this phase II trial was to determine the efficacy and safety of multimodal treatment for nonmetastatic ESFT. PROCEDURE: Patients with ESFT aged < 30 years were eligible for participation. The chemotherapy regimen consisted of vincristine, doxorubicin, and cyclophosphamide (VDC) alternating with ifosfamide and etoposide (IE) repeating every 21 days for 52 weeks. Local treatment included surgery and/or radiation therapy (0-55.8 Gy) based on the margin of resection and histologic response. The primary endpoint was progression-free survival (PFS) at three years. The study was designed to test whether the lower limit of the 90% confidence interval for PFS would exceed the threshold of 60%. The planned sample size was 53 patients, allowing for 10% of patients being ineligible. RESULTS: Of the 53 patients screened for entry, seven were deemed ineligible. Forty-six patients were considered as the per-protocol set and were used for the efficacy analysis. Three-year PFS was 71.7% (0.59-0.81). Estimated five-year PFS and overall survival were both 69.6%. Although no previously unknown adverse event was reported, three patients developed secondary malignancies (acute lymphoblastic leukemia, myelodysplastic syndrome, and osteosarcoma, one patient each). CONCLUSIONS: Multimodal treatment with standard VDC-IE chemotherapy improved the prognosis for patients with ESFT in Japan, although statistical confirmation of efficacy compared to historical control was not achieved.

Registration-directed phase 1/2 trial of irinotecan for pediatric solid tumors.

BACKGROUND: Although irinotecan hydrochloride (IRI) is a promising chemotherapeutic agent for pediatric solid tumors, its indications had been off-label in the USA, EU and Japan. Therefore, we conducted a phase 1/2 trial of IRI monotherapy in a registration-directed setting. METHODS: Children aged 2-18 years with solid tumors who were either refractory to or relapsed after standard chemotherapy were enrolled. Phase 1 was a conventional dose escalation study to determine the dose-limiting toxicity (DLT) and the recommended dose. IRI was given i.v. on days 1, 2, 3 and 8, 9, 10 in up to eight, 21 day cycles. RESULTS: The starting dose (40 mg/m2 /day) was determined to be the recommended dose because the next higher dose level (45 mg/m2 /day) resulted in two cases of DLT. Seventeen children (11 in phase 1 and six in phase 2) with a refractory solid tumor received IRI. Of the 12 patients treated with 40 mg/m2 /day, seven (58.3%) achieved a stable disease condition for >8 weeks. CONCLUSIONS: The RD of IRI in this treatment schedule was 40 mg/m2 /day. IRI did not cause tumor shrinkage but might help to stabilize refractory pediatric solid tumors. Based on the accumulating evidence from international studies of the efficacy of IRI against refractory pediatric solid tumors, the Japanese regulatory authority approved its use for this indication in 2011.

Phase I study of perifosine monotherapy in patients with recurrent or refractory neuroblastoma.

PURPOSE: Perifosine is an alkylphospholipid analog that inhibits or modulates signaling through signal transduction pathways such as Akt, which is enhanced in neuroblastoma (NB) by activation of tyrosine kinase receptors. We conducted a phase I study of perifosine in Japanese patients with recurrent or refractory NB. EXPERIMENTAL DESIGN: All patients enrolled were over 2 years of age; all had refractory or relapsed NB and a performance status of greater than 50%. Perifosine was orally administered at a loading dose (100-300 mg) on day 1 and at a maintenance dose (50-150 mg) from day 2 onward. Dose-limiting toxicity (DLT) and pharmacokinetics were assessed in Step 1 and safety and efficacy in Step 2. RESULTS: Nineteen patients were recruited. No DLT was observed. Adverse reactions occurring in more than 30% of the patients were vomiting (63%), nausea (53%), and diarrhea (37%). The mean plasma concentration of perifosine was 27.5 ± 9.8 µM on day 15 and 27.3 ± 11.5 µM on day 29. The response rate (RR) in 18 patients evaluable according to modified International Neuroblastoma Response Criteria was 0%; the disease control rate (DCR) was 56%. Median progression-free survival (PFS) was 122 days. In 11 patients evaluable according to the Response Evaluation Criteria in Solid Tumors, the RR and DCR were 9% and 55%, respectively. The median PFS was not reached. CONCLUSIONS: Perifosine monotherapy was well tolerated in Japanese patients with recurrent/refractory NB. Further investigations in combination with other anticancer or molecular targeted agents are warranted.

Hematopoietic stem cell transplantation for inborn errors of metabolism: A report from the Research Committee on Transplantation for Inborn Errors of Metabolism of the Japanese Ministry of Health, Labour and Welfare and the Working Group of the Japan Society for Hematopoietic Cell Transplantation.

A total of 216 patients with IEM were treated by allogeneic HSCT in Japan from 1985 until 2010. The results of UCBT have improved, and the OS rate of UCBT (81.9%) was not different from those of RBMT (87.2%) or UBMT (73.9%) in 2000-2010. However, EFS rates in RBMT (73.2%) and UBMT (62.2%) were better than that in UCBT (49.5%), and the difference between RBMT and UCBT was significant (p = 0.01). The EFS rate of patients conditioned by RIC (74.6%) was comparable or slightly better than in those who underwent MAC with irradiation (57.9%) or without irradiation (54.2%) in 2000-2010. A more pronounced trend was observed toward differential EFS for UCBT in 2000-2010: RIC (62.9%), MAC with irradiation (20.0%), and MAC without irradiation (42.1%). The difference between RIC and MAC with irradiation was significant (p < 0.03). In summary, we report a Japanese registry analysis of HSCT for IEM with improving survival in UCBT. The introduction of RIC after 2000 was considered to contribute to this improvement. UCBT could be recommended for those who lack an HLA-identical sibling donor.

Successful Pregnancy and Delivery After Radiation With Ovarian Shielding for Acute Lymphocytic Leukemia Before Menarche.

Total body irradiation is performed as a preconditioning regimen to inhibit graft-versus-host disease after bone marrow transplantation and to eradicate remaining tumor cells. However, these regimens result in delayed secondary sex characteristics and failure of ovarian function recovery, leading to amenorrhea and infertility. Herein, we report a case of an 11-year-old girl diagnosed with acute lymphocytic leukemia who received induction chemotherapy and prophylactic cranial irradiation. For bone marrow transplantation, she received total body irradiation of 12 Gy with uterine and ovarian shielding at 13 years of age. The patient remained in remission and menarche began at 14 years of age. At 23, she became pregnant and delivered a baby naturally with no abnormalities.

Residual blood volume in the umbilical cord of extremely premature infants.

BACKGROUND: The aim of this study was to investigate residual blood volume in the umbilical cord of extremely premature infants. METHODS: Twenty extremely premature infants were held at or below the placenta while the umbilical cord was clamped and cut at approximately 2-3 cm from the umbilicus within 30 s after birth. The umbilical cord was then clamped near the placenta to obtain a length of approximately 30 cm and cut. The residual blood volume in the segment of cord was drained and measured in milliliters. RESULTS: Mean birthweight was 846 ± 172 g (range, 587-1180 g). The average length of the clamped segment of umbilical cord was 29.8 ± 1.5 cm (range, 27-32 cm). Total residual blood volume and residual blood volume per cm were 15.5 ± 6.7 mL (range, 6-25 mL) and 0.5 ± 0.2 mL/cm (range, 0.2-0.8 mL/cm), respectively. The residual cord blood volume per kilogram of infant weight per 30 cm was 17.7 ± 5.5 mL/kg/30 cm (range, 8.9-29.0 mL/kg/30 cm). CONCLUSION: Infants could receive approximately 18 mL/kg of whole blood by one-time milking of 30 cm umbilical cord. With an average hematocrit of 40%, this volume is equivalent to approximately 13 mL of packed red blood cells (hematocrit 55%).

Prospective pharmacokinetic study of intravenous busulfan in hematopoietic stem cell transplantation in 25 children.

The aim of this study was to prospectively evaluate the PK and safety of ivBU in 25 Japanese children (median age six yr; range, five months-17 yr) as one of a combination of drugs in a pretransplant regimen. The patients had acute leukemia (n = 14), CML (2), JMML (5), solid tumors (2), chronic granulomatous disease (1), or metachromatic leukodystrophy (1). Five different dose schedules were used according to the patient's ABW: <9 kg (1.0 mg/kg), 9 to <16 (1.2 mg/kg), 16-23 (1.1 mg/kg), >23-34 (0.95 mg/kg), and >34 kg of BW (0.8 mg/kg). Each dose was given over two h, and sample blood was drawn at nine or 11 separate points for analysis by gas chromatography-mass spectrometry. The AUC varied from 796 to 1905 µmol min/L, and 19 of the 25 patients (76%) remained within the target range without dose adjustment. Two were diagnosed with engraftment failure. Hepatic VOD developed in four, and only one of these showed high AUC (>1500 µmol min/L). Toxicities did not correlate with the BU level. Our data showed very similar PK to those in previous studies, and these dose schedules are applicable to Japanese children.

Changes in cerebral blood oxygenation induced by active standing test in children with POTS and NMS.

Orthostatic dysregulation (OD) has been classified into subtypes by heart rate and blood pressure; however, the hemodynamics of brains have not yet been revealed. Therefore, we investigated changes in cerebral blood flow and oxygenation during an active standing test to clarify the pathophysiology of two subtypes: postural tachycardia syndrome (POTS) and neurally mediated syncope (NMS). We studied 31 children (15 boys, 16 girls; mean age, 14.0 ± 1.7 years) who presented with OD at the Department of Pediatrics and Child Health, Nihon University School of Medicine between 2009 and 2011. OD was diagnosed using the Japanese clinical guidelines for juvenile orthostatic dysregulation. After a 10-min resting period in the supine position, patients were asked to quickly stand up and keep upright for 10 min. Cerebral blood flow and cerebral oxygenation were measured using transcranial Doppler sonography and near-infrared spectroscopy. POTS showed a significant decrease of oxy-Hb and resistance index (RI), suggesting transient ischemia with maintainable cerebral autoregulation. NMS showed a decrease of oxy-Hb and an increase of RI, suggesting ischemia and impairment of autoregulation.

[Clinical efficacy and pharmacokinetics of lamotrigine for childhood-onset intractable epilepsy].

OBJECTIVE: We investigated the clinical efficacy and pharmacokinetics of lamotrigine (LTG) as an add-on therapy in childhood-onset intractable epilepsy. METHODS: We reviewed the charts of 28 outpatients who had received LTG as an add-on therapy. The data collected included epilepsy type, seizure frequency, concomitant anti-epileptic drugs, dosage of LTG and LTG serum levels. Furthermore, we reviewed the relationship between the LTG serum levels (microg/ml) and dosage of LTG (mg/kg/day), as well as the relationship between the LTG serum levels (microg/ml) and clinical efficacy in the following 2 groups:the valproate sodium (VPA) combination group and the non-VPA combination group. RESULTS: A reduction of 50% or more in seizure frequency was observed in 10 patients. In addition, there was a high correlation between the LTG serum levels and the dosage of LTG in each group. In the VPA combination group, the average of LTG serum levels in patients with adequate therapeutic response (50% reduction in seizure frequency) was higher than that in patients without adequate therapeutic response. In the non-VPA combination group, the average LTG serum level in adequate response patients was lower than that in patients without adequate therapeutic response. However, the epilepsy types of adequate response patients differed in the two groups. CONCLUSIONS: The LTG serum level is predictable based on the dosage of LTG. It was judged that the effective blood concentration of LTG differed when used with VPA, although factors other than the combined use of VPA should have been taken into consideration also.

Long-term efficacy of hematopoietic stem cell transplantation on brain involvement in patients with mucopolysaccharidosis type II: a nationwide survey in Japan.

Hematopoietic stem cell transplantation (HSCT) has not been indicated for patients with mucopolysaccharidosis II (MPS II, Hunter syndrome), while it is indicated for mucopolysaccharidosis I (MPS I) patients <2 years of age and an intelligence quotient (IQ) of ≥ 70. Even after the approval of enzyme replacement therapy for both of MPS I and II, HSCT is still indicated for patients with MPS I severe form (Hurler syndrome). To evaluate the efficacy and benefit of HSCT in MPS II patients, we carried out a nationwide retrospective study in Japan. Activities of daily living (ADL), IQ, brain magnetic resonance image (MRI) lesions, cardiac valvular regurgitation, and urinary glycosaminoglycan (GAG) were analyzed at baseline and at the most recent visit. We also performed a questionnaire analysis about ADL for an HSCT-treated cohort and an untreated cohort (natural history). Records of 21 patients were collected from eight hospitals. The follow-up period in the retrospective study was 9.6 ± 3.5 years. ADL was maintained around baseline levels. Cribriform changes and ventricular dilatation on brain MRI were improved in 9/17 and 4/17 patients, respectively. Stabilization of brain atrophy was shown in 11/17 patients. Cardiac valvular regurgitation was diminished in 20/63 valves. Urinary GAG concentration was remarkably lower in HSCT-treated patients than age-matched untreated patients. In the questionnaire analysis, speech deterioration was observed in 12/19 patients in the untreated cohort and 1/7 patient in HSCT-treated cohort. HSCT showed effectiveness towards brain or heart involvement, when performed before signs of brain atrophy or valvular regurgitation appear. We consider HSCT is worthwhile in early stages of the disease for patients with MPS II.

Usefulness of HbA1c to diagnose diabetes among Japanese children detected by a urine glucose screening program in the Tokyo Metropolitan Area.

We examined the correlation between plasma glucose (PG) and hemoglobin A1c (HbA1c) to evaluate the usefulness and limitations of applying the new diagnostic criteria for diabetes to Japanese pediatric patients. Data were collected from 298 school children who took an oral glucose tolerance test (OGTT) at a school-based urinary glucose screening program in the Tokyo Metropolitan Area between 1988 and 2009. Mean (SD) age of the children was 11.9 (2.5) years. Male-to-female ratio was 1:1.1. Children were diagnosed with renal glucosuria (n=146), diabetes mellitus (n=133), or the Japan Diabetes Society (JDS) "borderline type" (n=19). Median (range) values of fasting plasma glucose (FPG), 2-h plasma glucose in an OGTT (OGTT-2h), and HbA1c were 101 (76-378) mg/dL, 146.5 (57-563) mg/dL, and 6.05 (4.7-14.1) %. The correlation between PG and HbA1c was analyzed using least squares regression, and HbA1c was found to highly correlate with PG. From estimated regression equations, mean values of FPG and OGTT-2h corresponding to an HbA1c of 6.5% were calculated to be 111.4 mg/dL and 170.4 mg/dL. The mean values of HbA1c corresponding to an FPG of 126 mg/dL and OGTT-2h of 200 mg/dL were calculated to be 7.5% and 7.8%. The mean values of PG corresponding to HbA1c of 6.5% were lower than found in adults as analyzed by JDS. The mean values of HbA1c corresponding to diabetic type PG were higher than found in adults.

Insulin resistance at diagnosis in Japanese children with type 2 diabetes mellitus.

BACKGROUND: Insulin resistance at diagnosis was investigated in Japanese children with type 2 diabetes mellitus (T2DM). METHODS: A total of 160 children with T2DM were divided into groups on the basis of percent overweight at time of diagnosis: group A (n = 28), <20%; group B (n = 55), 20-39%; group C (n = 37), 40-59%; group D (n = 40), ≥ 60%. Indicators of insulin resistance at diagnosis were compared among the four patient groups, and also between the children with T2DM and the 201 age-matched normal Japanese children. RESULTS: There were no significant differences in plasma glucose (PG) levels among the four patient groups. The mean concentration of fasting plasma immunoreactive insulin (IRI) was significantly higher in group D than in groups A and B (39.2 µU/mL vs 16.2 µU/mL and 24.1 µU/mL, P < 0.05, respectively). The mean homeostasis model assessment (HOMA-R) was significantly higher in group D than in all the other three groups (17.6 vs 7.8, 10.8 and 12.7, P < 0.05, respectively). The indicators HOMA-R and fasting IRI were significantly higher in each diabetes group, even in non-obese group A, than in normal children (P < 0.01, respectively). CONCLUSIONS: Japanese children with T2DM had insulin resistance at diagnosis regardless of percent overweight, and the degree of insulin resistance gradually increased with rise in percent overweight.

Pregnant woman with an extremely small uterus due to pelvic irradiation in childhood.

A female cancer survivor, having suffered malignant lymphoma during childhood and received radio- and chemotherapy, became pregnant. Her uterus was extremely small and in the 22nd week of gestation, acute uterine contractions occurred, leading to preterm delivery and resulting in the death of the infant. Pelvic irradiation in childhood was considered to have caused a small uterus and thus brought on preterm delivery. The younger the patient, the more vulnerable the uterus is to irradiation. The exposure dose to the uterus in pediatric cancer patients should therefore be reduced, especially in younger patients. The cooperation of pediatric cancer specialists and obstetricians is necessary to preserve the future fertility of female cancer survivors.

Posterior reversible encephalopathy syndrome in childhood: report of four cases and review of the literature.

BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is a recently described disorder with typical radiological findings of bilateral gray and white matter abnormalities in the posterior regions of the cerebral hemispheres and cerebellum. Its clinical symptoms include headache, decreased alertness, mental abnormalities such as confusion, diminished spontaneity of speech, and changed behavior ranging from drowsiness to stupor, seizures, vomiting, and abnormalities of visual perception such as cortical blindness. In this study, the clinical and radiological findings of 4 children with this syndrome due to a variety of conditions are reported. METHODS: The records of 4 children with a diagnosis of PRES were retrospectively analyzed. RESULTS: PRES is associated with a disorder of cerebrovascular autoregulation of multiple etiologies. Four patients with PRES who had primary diagnoses of severe aplastic anemia, nephritic syndrome, Henoch-Schönlein purpura, and acute poststreptococcal glomerulonephritis are presented. This syndrome has been described in numerous medical conditions, including hypertensive encephalopathy, eclampsia, and with the use of immunosuppressive drugs. CONCLUSIONS: Early recognition of PRES as a complication during different diseases and therapies in childhood may facilitate precise diagnosis and appropriate treatment.

Acute encephalopathy with pandemic (H1N1) 2009 virus infection.

OBJECTIVES: In April 2009, a novel influenza A (H1N1) pdm virus was identified in Mexico and spread quickly around the world. However, the clinical features of acute encephalopathy associated with 2009 pandemic influenza have not yet been elucidated. METHODS: We treated 8 patients (3 boys and 5 girls) aged 4 to 11 years (average age, 8 y 3 months) with influenza virus-associated encephalopathy, who presented at our 2 hospitals between July 2009 and March 2010. We investigated the clinical characteristics, treatments, and outcomes in the patients. RESULTS: In all patients, brain computed tomography showed mild to severe diffuse cerebral edema, and electroencephalography revealed diffuse high-voltage slow waves. They were all treated with oseltamivir and methylprednisolone pulse therapy. Six patients recovered without any sequelae; however, the remaining 2 had residual neurological sequelae. These 2 patients presented with severe disturbance of consciousness, and their central nervous system symptoms appeared within 12 hours after the onset of fever. One patient had periventricular leukomalacia and symptomatic epilepsy by perinatal brain hypoxia, and the other patient had 1 complex febrile and 2 febrile seizures. CONCLUSIONS: This study showed that patients with influenza-associated encephalopathy caused by influenza A (H1N1) pdm infection were all older than those with seasonal influenza. Underlying neurological disease or history may be associated with poor prognosis.

Screening and treatment of childhood type 1 and type 2 diabetes mellitus in Japan.

A large number of children with type 2 diabetes mellitus (T2DM) and a small number with a slowly progressive form of type 1 diabetes mellitus (SPT1DM) have been detected by a urine glucose screening program conducted at Japanese schools since 1974. The incidence of T2DM in children has increased over the last 3 decades and is estimated to be approximately 3.0/100,000/year, which is twice as that of T1DM. In contrast, SPT1DM in children is more prevalent in Asians, particularly Japanese, and exhibits unique clinical features that differ from those of the rapid onset form of T1DM, usually seen in Caucasians. In the first part of this review, we summarize the urine glucose screening program conducted at Japanese schools and clinical characteristics of the 2 diabetic subtypes in Japanese children. In recent years, concerns regarding childhood diabetes in Asian countries, including Japan, have risen, and medical care for the same is exceedingly developing. Intensive insulin therapy such as basal-bolus therapy by multiple daily insulin injections and pump therapy, both using insulin analogs, has been increasing in pediatric patients with T1DM. In addition, various antidiabetic medications have been introduced for children with T2DM. In the second part of this review, we describe treatment of Japanese children with T1DM and T2DM and changes in glycemic control as a result of development of the treatment.

Pandemic (H1N1) 2009-associated pneumonia in children, Japan.

To describe clinical aspects of pandemic (H1N1) 2009 virus-associated pneumonia in children, we studied 80 such children, including 17 (21%) with complications, who were admitted to 5 hospitals in Japan during August-November 2009 after a mean of 2.9 symptomatic days. All enrolled patients recovered (median hospitalization 6 days). Timely access to hospitals may have contributed to favorable outcomes.

Relapse of aplastic anemia in children after immunosuppressive therapy: a report from the Japan Childhood Aplastic Anemia Study Group.

BACKGROUND: Although the therapeutic outcome of acquired aplastic anemia has improved markedly with the introduction of immunosuppressive therapy using antithymocyte globulin and cyclosporine, a significant proportion of patients subsequently relapse and require second-line therapy. However, detailed analyses of relapses in aplastic anemia children are limited. DESIGN AND METHODS: We previously conducted two prospective multicenter trials of immunosuppressive therapy for children with aplastic anemia: AA-92 and AA-97, which began in 1992 and 1997, respectively. In this study, we assessed the relapse rate, risk factors for relapse, and the response to second-line treatment in children with aplastic anemia treated with antithymocyte globulin and cyclosporine. RESULTS: From 1992 to 2007, we treated 441 children with aplastic anemia with standard immunosuppressive therapy. Among the 264 patients who responded to immunosuppressive therapy, 42 (15.9%) relapsed. The cumulative incidence of relapse was 11.9% at 10 years. Multivariate analysis revealed that relapse risk was significantly associated with an immunosuppressive therapy regimen using danazol (relative risk, 3.15; P=0.001) and non-severe aplastic anemia (relative risk, 2.51; P=0.02). Seventeen relapsed patients received additional immunosuppressive therapy with antithymocyte globulin and cyclosporine. Eight patients responded within 6 months. Seven of nine non-responders to second immunosuppressive therapy received hematopoietic stem cell transplantation and five are alive. Eleven patients underwent hematopoietic stem cell transplantation directly and seven are alive. CONCLUSIONS: In the present study, the cumulative incidence of relapse at 10 years was relatively low compared to that in other studies mainly involving adult patients. A multicenter prospective study is warranted to establish optimal therapy for children with aplastic anemia.