The prevalence of MS was 32%, which was significantly higher than in a healthy pediatric population. We recommend prolonged follow-up for transplant recipients, coupled with enforcement of preventive measures, such as early diagnosis and encouragement of a healthy lifestyle.

High-dose chemotherapy (HDC) followed by autologous stem cell rescue (ASCR) is the only curative treatment for metastatic retinoblastoma, but its feasibility in developing countries is unknown. We report 11 consecutive children (six unilateral) treated in three South-American middleincome countries with HDC-ASCR. One patient had metastatic retinoblastoma at diagnosis and the remaining ones had a metastatic relapse. Metastatic sites included BM ¼ 6, bone ¼ 4, orbit ¼ 5 and central nervous system (CNS) ¼ 4. All patients received induction with conventional chemotherapy achieving CR at a median of 5.7 months from the diagnosis of metastasis. Conditioning regimens included carboplatin and etoposide with thiotepa in six or with CY in four or melphalan in one patient. All patients engrafted after G-CSF-mobilized peripheral blood ASCR and no toxic deaths occurred. Two children received post-ASCR CNS radiotherapy. Seven children have disease-free survival (median follow-up 39 months). CNS relapse, isolated (n ¼ 3) or with systemic relapse (n ¼ 1), occurring at a median of 7 months after ASCT was the most common event. In the same period, five children with metastatic retinoblastoma did not qualify for HDC-ASCR and died. We conclude that HDC-ASCR is a feasible and effective treatment for children with metastatic retinoblastoma in middle-income countries.

Despite poor survival, controversies remain in the treatment for refractory or relapsed pediatric non-Hodgkin lymphoma (r/r NHL). The current project aimed to collect international experience on the re-induction treatment of r/r NHL, hematopoietic stem cell transplantation (HSCT), risk factors associated with outcome, and to suggest treatment recommendations. Inclusion criteria were (i) refractory disease, disease progression or relapse of any NHL subtype except anaplastic large cell lymphoma, (ii) age < 18 years at initial diagnosis, (iii) diagnosis in/after January 2000. Data from 639 eligible patients were evaluable. The eight-year probability of overall survival was 34 ± 2% with highly significant differences according to NHL subtypes: 28 ± 3% for 254 Burkitt lymphoma/leukemia, 50 ± 6% for 98 diffuse large B-cell lymphomas, 57 ± 8% for 41 primary mediastinal large B-cell lymphomas, 27 ± 3% for 177 T-lymphoblastic lymphomas, 52 ± 10% for 34 precursor-B-cell lymphoblastic lymphomas and 30 ± 9% for 35 patients with rare NHL subtypes. Subtype-specific factors associated with survival and treatment recommendations are suggested. There were no survivors without HSCT, except in few very small subgroups. Conclusions: There is an urgent need to further improve survival in r/r NHL. The current study provides the largest real-world series, which underlines the role of HSCT and suggests treatment recommendations.

HI-HSCT is feasible in our setting, offers a rational treatment option, and expands the donor pool significantly for children with high-risk leukemia in a developing country. This information is especially relevant to other ethnically diverse populations that are poorly represented in international donor registries.