Neuroblastoma is a malignancy of the developing sympathetic nervous system that often presents with widespread metastatic disease, resulting in survival rates of less than 50%1. To determine the spectrum of somatic mutation in high-risk neuroblastoma, we studied 240 cases using a combination of whole exome, genome and transcriptome sequencing as part of the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. Here we report a low median exonic mutation frequency of 0.60 per megabase (0.48 non-silent), and remarkably few recurrently mutated genes in these tumors. Genes with significant somatic mutation frequencies included ALK (9.2% of cases), PTPN11 (2.9%), ATRX (2.5%, an additional 7.1% had focal deletions), MYCN (1.7%, a recurrent p.Pro44Leu alteration), and NRAS (0.83%). Rare, potentially pathogenic germline variants were significantly enriched in ALK, CHEK2, PINK1, and BARD1. The relative paucity of recurrent somatic mutations in neuroblastoma challenges current therapeutic strategies reliant upon frequently altered oncogenic drivers.

This study discloses an encouraging EFS rate for children with nondisseminated MB treated with reduced-dose craniospinal radiation and chemotherapy. Additional, careful, step-wise reductions in CSRT in adequately staged patients may be possible.

A previous study (LMB89) of the French Society of Pediatric Oncology for childhood mature B-cell lymphoma (B-NHL) demonstrated a 92% 3-year event-free survival (EFS) for intermediate-risk group B defined as "non-resected" stage II/I and CNS-negative advanced-stage IIV/IV (70% of cases). We performed the FAB/LMB96 trial to assess the possibility of reducing treatment in children/adolescents with intermediate-risk B-NHL without jeopardizing survival. "Early responding" patients (tumor response > 20% at day 7) were randomized in a factorial design between 4 arms, 2 receiving half-dose of cyclophosphamide in the second induction course with cyclophosphamide, Oncovin (vincristine), prednisone, Adriamycin (doxorubicin), methotrexate (COPADM) and 2 not receiving the maintenance course M1. A total of 657 patients were randomized (May 1996 to June 2001) and 637 were analyzed. The analysis showed no significant effect of any of the treatment reductions on EFS and survival. The 4-year EFS was 93.4% and 90.9% in the groups with full-dose and half-dose of cyclophosphamide (RR = 1.3, P = .40) and 91.9% and 92.5% in the groups with and without M1 (RR = 1.01, P = .98). There was no interaction between the 2 treatment reductions or between each treatment reduction and LDH level or histologic subtypes (Burkitt/Burkitt-like or large B-cell). Children/adolescents with intermediate-risk B-NHL who have an early response and achieve a complete remission after the first consolidation course can be cured with a 4-course treatment with a total dose of only 3.3 g/m2 cyclophosphamide and 120 mg/m2 doxorubicin.

The prognosis for higher risk childhood B-cell non-Hodgkin lymphoma has improved over the past 20 years but the optimal intensity of treatment has yet to be determined. Children 21 years old or younger with newly diagnosed B-cell nonHodgkin lymphoma/B-cell acute lymphoblastic leukemia (B-NHL/B-ALL) with higher risk factors (bone marrow [BM] with or without CNS involvement) were randomized to standard intensity FrenchAmerican-British/Lymphoma Malignancy B (FAB/LMB) therapy or reduced intensity (reduced cytarabine plus etoposide and deletion of 3 maintenance courses M2, M3, M4). All patients with CNS disease had additional high-dose methotrexate (8 g/m 2 ) plus extra intrathecal therapy. Fifty-one percent had BM involvement, 20% had CNS involvement, and 29% had BM and CNS involvement. One hundred ninety patients were randomized. The probabilities of 4-year event-free survival (EFS) and survival (S) were 79% ؎ 2.7% and 82% ؎ 2.6%, respectively. In patients in remission after 3 cycles who were randomized to standard versus reducedintensity therapy, the 4-year EFS after randomization was 90% ؎ 3.1% versus 80% ؎ 4.2% (one-sided P ‫؍‬ .064) and S was 93% ؎ 2.7% versus 83% ؎ 4.0% (onesided P ‫؍‬ .032). Patients with either combined BM/CNS disease at diagnosis or poor response to cyclophosphamide, Oncovin [vincristine], prednisone (COP) reduction therapy had a significantly inferior EFS and S (P < .001). Standardintensity FAB/LMB therapy is recommended for children with high-risk B-NHL (B-ALL with or without CNS involvement).