Recent studies have demonstrated the protective effect of cytomegalovirus (CMV) reactivation against relapse after allogeneic hematopoietic stem cell transplantation (HSCT) for adult myeloid malignancies. We assessed the association of CMV reactivation, defined as the development of CMV antigenemia (at least 1 pp65 antigen-positive cell per 5.0 × 10(4) WBCs) within 100 days after HSCT, with the risk of relapse in 143 patients with pediatric acute leukemia. The median age at HSCT was 7 years, and underlying diseases included acute lymphoblastic leukemia in 101 patients and acute myeloid leukemia in 42. The cumulative incidence of CMV reactivation at day 100 after HSCT was 45.4%. At a median follow-up of 88 months, patients with CMV reactivation had significantly lower 5-year cumulative incidence of relapse compared with patients without CMV reactivation. In a multivariate analysis, high-level CMV reactivation (≥10 pp65 antigen-positive cells) was an independent factor associated with reduced relapse. However, CMV reactivation was also associated with higher nonrelapse mortality (NRM), mostly caused by opportunistic infection after grades II to IV acute graft-versus-host disease (GVHD), which resulted in decreased probability of survival. High-level CMV reactivation was a risk factor for increased NRM and worse overall survival in multivariate analysis. Although CMV reactivation may reduce the risk of relapse after HSCT for pediatric acute leukemia, effective management of severe acute GVHD and better prophylaxis and treatment of opportunistic infections are required to reduce the incidence of NRM and improve survival. Further studies on pediatric HSCT that include a larger number of patients and more homogenous patient cohorts are desirable.

We report the long-term morbidity and mortality of 105 pediatric patients who developed chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). According to the consensus criteria of the National Institutes of Health, the global severity of cGVHD was mild in 26 patients (25%), moderate in 30 patients (29%), and severe in 49 patients (47%). Patients with severe cGVHD had a significantly lower cumulative incidence of cGVHD remission and higher probability of continuing cGVHD at 8 years from cGVHD diagnosis compared with those with mild or moderate cGVHD. The 10-year cumulative incidence of nonrelapse mortality in severe cGVHD patients was significantly higher and the probability of disease-free survival was significantly lower than those among patients with mild and moderate cGVHD. Of the 59 patients who survived for more than 5 years, 20 (34%) (4 with moderate and 16 with severe cGVHD) had persistent functional impairment caused by cGVHD with a Karnofsky/Lansky performance score of 90% in 3 patients, 80% in 4 patients, and below 70% in 13 patients at the time of relapse, death, or last follow-up. Better therapeutic strategies are needed to lower the incidence of severe cGVHD, considering the longer life expectancy of pediatric HSCT survivors.

Refractory cytopenia of childhood (RCC) is the most common subtype of myelodysplastic syndrome in children, and the clinical course of RCC is heterogeneous. A certain proportion of RCC patients need allogeneic hematopoietic stem cell transplantation (HSCT); however, data on HSCT outcomes are not abundant, and the optimal intensity of a preparative conditioning regimen remains uncertain. In this study, we evaluated the outcomes of HSCT in 24 patients with RCC. Eleven patients received myeloablative conditioning (MAC) consisting of high-dose cytarabine, cyclophosphamide, and either total body irradiation (TBI) or busulfan. Nine patients (38%) received a reduced-intensity conditioning (RIC) regimen; of these, 7 received low-dose TBI and cyclophosphamide (200 mg/kg) with or without antithymocyte globulin or fludarabine, and 2 patients received low-dose TBI, fludarabine, and melphalan (140 mg/m(2)). The remaining 4 patients had disease progression before HSCT and received the MAC regimen. With a median follow-up of 91 months (range, 6 to 263), the probability of overall survival at 5 years was 81.1% (95% CI, 57.0 to 92.5). The 5-year overall survival for the 15 patients who received MAC was 73.3% (95% CI, 43.6 to 89.1), and all 9 patients with RIC are alive without any events. Further study is needed to evaluate the efficacy of RIC for children with RCC with an expectation for reduction of late effects such as growth retardation and infertility.

Our results indicated that in case of tolerable patient condition, further re-induction chemotherapy might be reasonable so that SCT could be performed in CR, which might result in a low incidence of relapse after SCT. Novel approaches are required to induce CR for the treatment of children with relapsed/refractory ALL.

B‐cell expansion with NF‐κB (nuclear factor‐kappa B) and T‐cell anergy (BENTA) is a rare congenital lymphoproliferative disorder caused by germline gain‐of‐function mutations in the CARD11 gene. We herein report a familial case of BENTA due to a G123D heterozygous missense mutation in CARD11 inherited by a male from his mother. The mother's clinical course was characterized by polyarthritis and encephalitis in young adulthood, suggesting that autoimmune‐like manifestations can occur in BENTA. The B‐cell lymphocytosis and splenomegaly seen in her child have been managed with prednisolone and tacrolimus. Further investigations are needed to evaluate the efficacy of calcineurin inhibitors for BENTA.