High-throughput genomic analyses may improve outcomes in patients with advanced cancers. MOSCATO 01 is a prospective clinical trial evaluating the clinical benefit of this approach. Nucleic acids were extracted from fresh-frozen tumor biopsies and analyzed by array comparative genomic hybridization, next-generation sequencing, and RNA sequencing. The primary objective was to evaluate clinical benefit as measured by the percentage of patients presenting progression-free survival (PFS) on matched therapy (PFS2) 1.3-fold longer than the PFS on prior therapy (PFS1). A total of 1,035 adult patients were included, and a biopsy was performed in 948. An actionable molecular alteration was identified in 411 of 843 patients with a molecular portrait. A total of 199 patients were treated with a targeted therapy matched to a genomic alteration. The PFS2/PFS1 ratio was >1.3 in 33% of the patients (63/193). Objective responses were observed in 22 of 194 patients (11%; 95% CI, 7%–17%), and median overall survival was 11.9 months (95% CI, 9.5–14.3 months). Significance: This study suggests that high-throughput genomics could improve outcomes in a subset of patients with hard-to-treat cancers. Although these results are encouraging, only 7% of the successfully screened patients benefited from this approach. Randomized trials are needed to validate this hypothesis and to quantify the magnitude of benefit. Expanding drug access could increase the percentage of patients who benefit. Cancer Discov; 7(6); 586–95. ©2017 AACR. See related commentary by Schram and Hyman, p. 552. This article is highlighted in the In This Issue feature, p. 539

Ewing sarcoma (ES) is an aggressive sarcoma of bone and soft tissue occurring at any age with a peak incidence in adolescents and young adults. The treatment of ES relies on a multidisciplinary approach, coupling risk-adapted intensive neoadjuvant and adjuvant chemotherapies with surgery and/or radiotherapy for control of the primary site and possible metastatic disease. The optimization of ES multimodality therapeutic strategies has resulted from the efforts of several national and international groups in Europe and North America and from cooperation between pediatric and medical oncologists. Successive first-line trials addressed the efficacy of various cyclic combinations of drugs incorporating doxorubicin, vincristine, cyclophosphamide, ifosfamide, etoposide, and dactinomycin and identified prognostic factors now used to tailor therapies. The role of high-dose chemotherapy is still debated. Current 5-year overall survival for patients with localized disease is 65% to 75%. Patients with metastases have a 5-year overall survival < 30%, except for those with isolated pulmonary metastasis (approximately 50%). Patients with recurrence have a dismal prognosis. The many insights into the biology of the EWS-FLI1 protein in the initiation and progression of ES remain to be translated into novel therapeutic strategies. Current options and future approaches will be discussed.

Ewing sarcoma is a primary bone tumor initiated by EWSR1–ETS gene fusions. To identify secondary genetic lesions that contribute to tumor progression, we performed whole-genome sequencing of 112 Ewing sarcoma samples and matched germline DNA. Overall, Ewing sarcoma tumors had relatively few single-nucleotide variants, indels, structural variants, and copy-number alterations. Apart from whole chromosome arm copy-number changes, the most common somatic mutations were detected in STAG2 (17%), CDKN2A (12%), TP53 (7%), EZH2, BCOR, and ZMYM3 (2.7% each). Strikingly, STAG2 mutations and CDKN2A deletions were mutually exclusive, as confirmed in Ewing sarcoma cell lines. In an expanded cohort of 299 patients with clinical data, we discovered that STAG2 and TP53 mutations are often concurrent and are associated with poor outcome. Finally, we detected subclonal STAG2 mutations in diagnostic tumors and expansion of STAG2-immunonegative cells in relapsed tumors as compared with matched diagnostic samples. Significance: Whole-genome sequencing reveals that the somatic mutation rate in Ewing sarcoma is low. Tumors that harbor STAG2 and TP53 mutations have a particularly dismal prognosis with current treatments and require alternative therapies. Novel drugs that target epigenetic regulators may constitute viable therapeutic strategies in a subset of patients with mutations in chromatin modifiers. Cancer Discov; 4(11); 1342–53. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 1243

Purpose: To improve the poor prognosis of patients with primary disseminated multifocal Ewing sarcomas (PDMES) with a dose-intense treatment concept. Patients and Methods: From 1999 to 2005, 281 patients with PDMES were enrolled onto the Euro-EWING 99 R3 study. Median age was 16.2 years (range, 0.4 to 49 years). Recommended treatment consisted of six cycles of vincristine, ifosfamide, doxorubicin, and etoposide (VIDE), one cycle of vincristine, dactinomycin, and ifosfamide (VAI), local treatment (surgery and/or radiotherapy), and high-dose busulfan-melphalan followed by autologous stem-cell transplantation (HDT/SCT). Results: After a median follow-up of 3.8 years, event-free survival (EFS) and overall survival (OS) at 3 years for all 281 patients were 27% ± 3% and 34% ± 4% respectively. Six VIDE cycles were completed by 250 patients (89%); 169 patients (60%) received HDT/SCT. The estimated 3-year EFS from the start of HDT/SCT was 45% for 46 children younger than 14 years. Cox regression analyses demonstrated increased risk at diagnosis for patients older than 14 years (hazard ratio [HR] = 1.6), a primary tumor volume more than 200 mL (HR = 1.8), more than one bone metastatic site (HR = 2.0), bone marrow metastases (HR = 1.6), and additional lung metastases (HR = 1.5). An up-front risk score based on these HR factors identified three groups with EFS rates of 50% for score ≤ 3 (82 patients), 25% for score more than 3 to less than 5 (102 patients), and 10% for score ≥ 5 (70 patients; P < .0001). Conclusion: PDMES patients may survive with intensive multimodal therapy. Age, tumor volume, and extent of metastatic spread are relevant risk factors. A score based on these factors may facilitate risk-adapted treatment approaches.

Non-Hodgkin lymphoma is the fourth most common malignancy in children, has an even higher incidence in adolescents, and is primarily represented by only a few histologic subtypes. Dramatic progress has been achieved, with survival rates exceeding 80%, in large part because of a better understanding of the biology of the different subtypes and national and international collaborations. Most patients with Burkitt lymphoma and diffuse large B-cell lymphoma are cured with short intensive pulse chemotherapy containing cyclophosphamide, cytarabine, and high-dose methotrexate. The benefit of the addition of rituximab has not been established except in the case of primary mediastinal B-cell lymphoma. Lymphoblastic lymphoma is treated with intensive, semi-continuous, longer leukemia-derived protocols. Relapses in B-cell and lymphoblastic lymphomas are rare and infrequently curable, even with intensive approaches. Event-free survival rates of approximately 75% have been achieved in anaplastic large-cell lymphomas with various regimens that generally include a short intensive B-like regimen. Immunity seems to play an important role in prognosis and needs further exploration to determine its therapeutic application. ALK inhibitor therapeutic approaches are currently under investigation. For all pediatric lymphomas, the intensity of induction/consolidation therapy correlates with acute toxicities, but because of low cumulative doses of anthracyclines and alkylating agents, minimal or no long-term toxicity is expected. Challenges that remain include defining the value of prognostic factors, such as early response on positron emission tomography/computed tomography and minimal disseminated and residual disease, using new biologic technologies to improve risk stratification, and developing innovative therapies, both in the first-line setting and for relapse.

PURPOSE: To evaluate a strategy that avoids radiotherapy in first-line treatment in children under 5 years of age with brain or posterior fossa ependymoma, by exclusively administering 16 months of adjuvant multiagent chemotherapy after surgery. PATIENTS AND METHODS: Between June 1990 and October 1998, 73 children with ependymoma (82% with high-grade tumors) were enrolled onto this multicenter trial. Children received adjuvant conventional chemotherapy after surgery consisting of seven cycles of three courses alternating two drugs at each course (procarbazine and carboplatin, etoposide and cisplatin, vincristine and cyclophosphamide) over a year and a half. Systematic irradiation was not envisaged at the end of chemotherapy. In the event of relapse or progression, salvage treatment consisted of a second surgical procedure followed by local irradiation with or without second-line chemotherapy. RESULTS: Conventional chemotherapy was well tolerated and could be administered in outpatient clinics. No radiologically documented response to chemotherapy more than 50% was observed. With a median follow-up of 4.7 years (range, 5 months to 8 years), the 4-year progression-free survival rate in this series was 22% (95% confidence interval [CI], 13% to 43%) and the overall survival rate was 59% (95% CI, 47% to 71%). Overall, 40% (95% CI, 29% to 51%) of the patients were alive having never received radiotherapy 2 years after the initiation of chemotherapy and 23% (95% CI, 14% to 35%) were still alive at 4 years without recourse to this modality. In the multivariate analysis, the two factors associated with a favorable outcome were a supratentorial tumor location (P = .0004) and complete surgery (P = .0009). Overall survival at 4 years was 74% (95% CI, 59% to 86%) for the patients in whom resection was radiologically complete and 35% (95% CI, 18% to 56%) for the patients with incomplete resection. CONCLUSION: A significant proportion of children with ependymoma can avoid radiotherapy with prolonged adjuvant chemotherapy. Deferring irradiation at the time of relapse did not compromise overall survival of the entire patient population.