Genomic ALK alterations in primary and relapsed neuroblastoma.

BACKGROUND: Genomic alterations of the anaplastic lymphoma kinase gene (ALK) occur recurrently in neuroblastoma, a pediatric malignancy of the sympathetic nervous system. However, information on their development over time has remained sparse. METHODS: ALK alterations were assessed in neuroblastomas at diagnosis and/or relapse from a total of 943 patients, covering all stages of disease. Longitudinal information on diagnostic and relapsed samples from individual patients was available in 101 and 102 cases for mutation and amplification status, respectively. RESULTS: At diagnosis, ALK point mutations occurred in 10.5% of all cases, with highest frequencies in stage 4 patients <18 months. At relapse, ALK alteration frequency increased by 70%, both in high-risk and non-high-risk cases. The increase was most likely due to de novo mutations, frequently leading to R1275Q substitutions, which are sensitive to pharmacological ALK inhibition. By contrast, the frequency of ALK amplifications did not change over the course of the disease. ALK amplifications, but not mutations, were associated with poor patient outcome. CONCLUSIONS: The considerably increased frequency of ALK mutations at relapse and their high prevalence in young stage 4 patients suggest surveying the genomic ALK status regularly in these patient cohorts, and to evaluate ALK-targeted treatment also in intermediate-risk patients.

Image-defined risk factors in localized thoracic neuroblastoma and ganglioneuroma.

BACKGROUND: The pretreatment International Neuroblastoma Risk Group Staging System (INRGSS) discriminates localized tumors L1/L2 depending on the absence/presence of image-defined risk factors (IDRFs) at diagnosis. Referring to this new staging system, we assessed initial imaging of localized thoracic neuroblastoma (NB) and ganglioneuroma (GN) and the extent of initial tumor resection. METHODS: Patients with localized thoracic NB/GN from the German clinical trials NB97 and NB2004 were included. Imaging at diagnosis and operative reports were reviewed retrospectively. IDRFs were assessed centrally and correlated to International Neuroblastoma Staging System (INSS) stage and extent of tumor resection. Additionally, we analyzed data on surgery-related complications. RESULTS: Imaging series of 88 patients were available for central review. In 18 children, no IDRF was present, 28 exhibited one IDRF, 42 two or more IDRFs, resulting in 70 patients with L2 disease. The most frequently observed IDRF was encasement of any vessel (n = 38). Initial surgical resection was aimed for in 45 patients (L1: n = 11; L2: n = 34). Complete and gross total resection rates were higher children with L2 NB (n = 8/25 L1, n = 17/25 L2 vs. n = 2/15 L1, n = 13/15 L2, respectively). The proportion of surgical complications was very similar between INRGSS L1 and L2 (n = 4/11 vs. n = 17/34). All complications were manageable, and no surgery-related deaths were observed. CONCLUSION: In this retrospective cohort, the extent of resection and the rate of surgical complications did not differ substantially between patients classified as L1/L2, indicating that INRGSS L2 does not equate unresectability. It appeared that individual IDRFs differ in value. Larger studies are needed to assess the significance and therapeutic/prognostic impact of such findings.

Comparing presentations and outcomes of children with cancer: a study between a lower-middle-income country and a high-income country.

BACKGROUND: Substantial progress has been achieved in managing childhood cancers in many high-income countries (HICs). In contrast, survival rates in lower-middle-income countries (LMICs) are less favorable. Here, we aimed to compare outcomes and associated factors between two large institutions; Egypt (LMIC) and Germany (HIC). METHODS: A retrospective review was conducted on newly diagnosed children with cancer between 2006 and 2010 in the departments of pediatric oncology at the South Egypt Cancer Institute (SECI) (n = 502) and the University Hospital of Cologne-Uniklinik Köln (UKK) (n = 238). Characteristics including age, sex, diagnosis, travel time from home to the cancer center, the time interval from initial symptoms to the start of treatment, treatment-related complications, compliance, and outcome were analyzed. A Cox proportional hazards regression model was applied to investigate the influence of risk factors. RESULTS: The most common diagnoses in SECI were leukemia (48.8%), lymphomas (24.1%), brain tumors (1%), and other solid tumors (24.7%), compared to 22.3%, 19.3%, 28.6%, and 26.5% in UKK, respectively. Patients from SECI were younger (5.2 vs. 9.0 years, P < 0.001), needed longer travel time to reach the treatment center (1.44 ± 0.07 vs. 0.53 ± 0.03 h, P < 0.001), received therapy earlier (7.53 ± 0.59 vs. 12.09 ± 1.01 days, P = 0.034), showed less compliance (85.1% vs. 97.1%, P < 0.001), and relapsed earlier (7 vs. 12 months, P = 0.008). Deaths in SECI were more frequent (47.4% vs. 18.1%) and caused mainly by infection (60% in SECI, 7% in UKK), while in UKK, they were primarily disease-related (79% in UKK, 27.7% in SECI). Differences in overall and event-free survival were observed for leukemias but not for non-Hodgkin lymphoma. CONCLUSIONS: Outcome differences were associated with different causes of death and other less prominent factors.

Hypercalcemia is a frequent side effect of 13-cis-retinoic acid treatment in patients with high-risk neuroblastoma.

PURPOSE: 13-cis-Retinoic acid (13-cisRA) is used as a postconsolidation treatment in patients with high-risk neuroblastoma. Hypercalcemia is a known side effect of retinoids. Frequency, symptoms, treatment, and risk factors for hypercalcemia were analyzed. PATIENTS: Data were retrospectively analyzed for 350 patients registered in the German Neuroblastoma trials NB97 and NB04 who were treated with high-risk protocols-including myeloablative chemotherapy with autologous stem cell transplantation (SCT) or maintenance therapy-and had received 13-cisRA between January 1, 2000 and December 31, 2010. RESULTS: Hypercalcemia was reported in 78 patients (22.3%), and 37 patients (10.6%) developed Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or 4 hypercalcemia. The calcium levels were 2.5-4.6 mmol/L (median 3.1 mmol/L). Patients with a single kidney were at a higher risk of developing hypercalcemia (p = .001). Regarding postinduction treatment, 69 of 280 patients with SCT (24.6%) and nine of 70 patients without SCT (12.9%) developed hypercalcemia during 13-cisRA treatment (p = .037). Most patients developed hypercalcemia in the first cycle of 13-cisRA, and only in a single cycle. Hypercalcemia symptoms were frequent but moderate. In most patients, treatment with 13-cisRA was continued without dose reduction in subsequent cycles. CONCLUSION: In this cohort, grades 3 and 4 hypercalcemia were observed more often than previously reported. A single kidney and pretreatment with myeloablative chemotherapy with stem cell transplantation were identified as potential risk factors for the development of hypercalcemia.

Multiple mechanisms disrupt the let-7 microRNA family in neuroblastoma.

Poor prognosis in neuroblastoma is associated with genetic amplification of MYCN. MYCN is itself a target of let-7, a tumour suppressor family of microRNAs implicated in numerous cancers. LIN28B, an inhibitor of let-7 biogenesis, is overexpressed in neuroblastoma and has been reported to regulate MYCN. Here we show, however, that LIN28B is dispensable in MYCN-amplified neuroblastoma cell lines, despite de-repression of let-7. We further demonstrate that MYCN messenger RNA levels in amplified disease are exceptionally high and sufficient to sponge let-7, which reconciles the dispensability of LIN28B. We found that genetic loss of let-7 is common in neuroblastoma, inversely associated with MYCN amplification, and independently associated with poor outcomes, providing a rationale for chromosomal loss patterns in neuroblastoma. We propose that let-7 disruption by LIN28B, MYCN sponging, or genetic loss is a unifying mechanism of neuroblastoma development with broad implications for cancer pathogenesis.

Confirmatory adaptive group sequential designs for single-arm phase II studies with multiple time-to-event endpoints.

Existing methods concerning the assessment of long-term survival outcomes in one-armed trials are commonly restricted to one primary endpoint. Corresponding adaptive designs suffer from limitations regarding the use of information from other endpoints in interim design changes. Here we provide adaptive group sequential one-sample tests for testing hypotheses on the multivariate survival distribution derived from multi-state models, while making provision for data-dependent design modifications based on all involved time-to-event endpoints. We explicitly elaborate application of the methodology to one-sample tests for the joint distribution of (i) progression-free survival (PFS) and overall survival (OS) in the context of an illness-death model, and (ii) time to toxicity and time to progression while accounting for death as a competing event. Large sample distributions are derived using a counting process approach. Small sample properties are studied by simulation. An already established multi-state model for non-small cell lung cancer is used to illustrate the adaptive procedure.

Clinical and molecular characterization of patients with stage 4(M) neuroblastoma aged less than 18 months without MYCN amplification.

INTRODUCTION: The survival of children with stage 4(M) neuroblastoma without MYCN amplification and below the age of 18 months is considered better than the still dismal outcome of older high-risk neuroblastoma patients. This study analyzes the impact of clinical and molecular characteristics on the long-term outcome. PATIENTS AND METHODS: Clinical presentation, survival, and recurrence patterns of patients enrolled onto trials NB90, NB97, and NB2004 were retrospectively analyzed. Gene expression signatures based on RNA microarrays (TH10) were investigated if tumor material was available. RESULTS: Between 1990 and 2015, 177 patients with stage 4(M) MYCN nonamplified neuroblastoma aged less than 18 months at diagnosis were eligible. After a median follow-up of 9.7 years (IQR 5.0, 13.4), the proportions of 10-year event-free survival (EFS) and overall survival (OS) were 73% (95% confidence interval [CI] 67-79%) and 86% (95% CI 80-92%), respectively. Of the 27 neuroblastoma recurrences, 44% occurred in more than one site. Four additional patients presented histologically mature ganglioneuroma at recurrence. Six patients developed a secondary malignancy. The secondary 5-year EFS and OS of the 27 patients with neuroblastoma recurrence were 44% and 59%, respectively. TH10 gene expression signature was not prognostically predictive in the investigated subcohort. CONCLUSION: The outcome of patients with stage 4(M) neuroblastoma aged less than 18 months is favorable when treated with high-risk or otherwise intensive therapy. The development of secondary malignancies and the potential of maturation to ganglioneuroma call for a controlled stepwise reduction of treatment intensity.

The reliability of bone marrow cytology as response criterion in metastatic neuroblastoma.

BACKGROUND: The quantitative assessment of neuroblastoma cell content in bone marrow aspirates for response evaluation has been introduced recently. Data on the concordance of interobserver reports are lacking so far. METHODS: Investigators of seven European countries representing national reference or large oncological centers convened in 2016. They agreed to quantitatively assess routine bone marrow smears of the participating institutions and to discuss the discrepant results in joint meetings. RESULTS: From 2017 through 2019, three cytology rounds with 24, 28, and 28 bone marrow samples were run evaluating the representativity of the smears (yes/[restricted]/no) and the presence of tumor cells (yes/no and %). The comparison of the reports using κ (Fleiss) and α (Krippendorff) statistics demonstrated no robust reliabilities. The agreement on the representativity was moderate to poor, on the presence of tumor cells moderate to good, and on the percentage of tumor cells slight to moderate. Though the value of cytology is unquestioned to detect even tiny metastatic cells in bone marrow, the investigators unanimously agreed that a reliable quantification of the tumor cell content in bone marrow smears is unrealistic. For the key issue of representativity, a new practical definition was developed. CONCLUSION: For any work with bone marrow aspirates, the representativity of the material is of paramount importance. A practical definition is proposed. A reliable quantitative cytological assessment of tumor cell content in bone marrow aspirates is not feasible in metastatic neuroblastoma. Therefore, its use as response criterion should be reconsidered.

A nomogram of clinical and biologic factors to predict survival in children newly diagnosed with high-risk neuroblastoma: An International Neuroblastoma Risk Group project.

BACKGROUND: Long-term outcome remains poor for children with high-risk neuroblastoma (five-year overall survival [OS] ∼50%). Our objectives were to (a) identify prognostic biomarkers and apply them in a nomogram to identify the subgroup of ultra-high-risk patients at highest risk of disease progression/death, for whom novel frontline therapy is urgently needed; and (b) validate the nomogram in an independent cohort. METHODS: A total of 1820 high-risk patients (≥18 months old with metastatic neuroblastoma), diagnosed 1998-2015, from the International Neuroblastoma Risk Groups (INRG) Data Commons were analyzed in a retrospective cohort study. Using multivariable Cox regression of OS from diagnosis, a nomogram was created from prognostic biomarkers to predict three-year OS. External validation was performed using the SIOPEN HR-NBL1 trial cohort (n = 521), evidenced by receiver operating characteristic curves. RESULTS: The nomogram, including MYCN status (P < 0.0001), lactate dehydrogenase (LDH) (P = 0.0007), and presence of bone marrow metastases (P = 0.004), had robust performance and was validated. Applying the nomogram at diagnosis (a) gives prognosis of an individual patient and (b) identifies patients predicted to have poor outcome (three-year OS was 30% ± 5% for patients with a nomogram score of > 82 points; 58% ± 1% for those ≤82 points). Median follow-up time was 5.5 years (range, 0-14.1). CONCLUSIONS: In high-risk neuroblastoma, a novel, publicly available nomogram using prognostic biomarkers (MYCN status, LDH, presence of bone marrow metastases; https://neuroblastoma.shinyapps.io/High-Risk-Neuroblastoma-Nomogram/) has the flexibility to apply a clinically suitable and context-specific cutoff to identify patients at highest risk of death. This will facilitate testing urgently needed new frontline treatment options to improve outcome for these children.

Telomerase activation by genomic rearrangements in high-risk neuroblastoma.

Neuroblastoma is a malignant paediatric tumour of the sympathetic nervous system. Roughly half of these tumours regress spontaneously or are cured by limited therapy. By contrast, high-risk neuroblastomas have an unfavourable clinical course despite intensive multimodal treatment, and their molecular basis has remained largely elusive. Here we have performed whole-genome sequencing of 56 neuroblastomas (high-risk, n = 39; low-risk, n = 17) and discovered recurrent genomic rearrangements affecting a chromosomal region at 5p15.33 proximal of the telomerase reverse transcriptase gene (TERT). These rearrangements occurred only in high-risk neuroblastomas (12/39, 31%) in a mutually exclusive fashion with MYCN amplifications and ATRX mutations, which are known genetic events in this tumour type. In an extended case series (n = 217), TERT rearrangements defined a subgroup of high-risk tumours with particularly poor outcome. Despite a large structural diversity of these rearrangements, they all induced massive transcriptional upregulation of TERT. In the remaining high-risk tumours, TERT expression was also elevated in MYCN-amplified tumours, whereas alternative lengthening of telomeres was present in neuroblastomas without TERT or MYCN alterations, suggesting that telomere lengthening represents a central mechanism defining this subtype. The 5p15.33 rearrangements juxtapose the TERT coding sequence to strong enhancer elements, resulting in massive chromatin remodelling and DNA methylation of the affected region. Supporting a functional role of TERT, neuroblastoma cell lines bearing rearrangements or amplified MYCN exhibited both upregulated TERT expression and enzymatic telomerase activity. In summary, our findings show that remodelling of the genomic context abrogates transcriptional silencing of TERT in high-risk neuroblastoma and places telomerase activation in the centre of transformation in a large fraction of these tumours.

The prognostic strength of serum LDH and serum ferritin in children with neuroblastoma: A report from the International Neuroblastoma Risk Group (INRG) project.

PURPOSE: Age, MYCN status, stage, and histology have been used as neuroblastoma (NB) risk factors for decades. Serum lactate dehydrogenase (LDH) and serum ferritin are reproducible, easily obtained, and prognostic, though never used in risk stratification, except one German trial. We analyzed the prognostic strength of LDH and ferritin, overall, within high-risk NB, and by era, using the International Neuroblastoma Risk Group Data Commons. PATIENTS AND METHODS: Children with NB (1990-2016) were categorized into LDH (n = 8867) and ferritin (n = 8575) risk groups using EFS. Cox models compared the prognostic strength of LDH and ferritin to age, MYCN status, and INSS stage. RESULTS: Higher LDH conferred worse EFS, overall (5-year EFS) (100-899 IU/L: 76 ± 0.6%; 0-99 or 900-1399 IU/L: 60 ± 1.2%; ≥1400 IU/L: 36 ± 1.2%; P < .0001), and in high-risk NB post-2009 (3-year EFS) (117-381 IU/L: 67 ± 8.9%; 382-1334 IU/L: 58 ± 4.4%; 0-116 or ≥1335 IU/L: 46 ± 3.9%; P = .003). Higher ferritin conferred worse EFS, overall (5-year EFS) (1-29 ng/mL: 87 ± 0.9%; 0 or 30-89 ng/mL: 74 ± 0.8%; ≥90 ng/mL: 48 ± 0.9%; P < .0001), and in high-risk NB post-2009 (3-year EFS) (1-53 ng/mL: 71 ± 9.3%; 0 or 54-354 ng/mL: 55 ± 4.7%; ≥355 ng/mL: 34 ± 6.1%; P = .0008). In multivariable analyses adjusting for age, MYCN, and stage, LDH and ferritin maintained independent prognostic ability (P < .0001; adjusted HRs (95% CI): 1.7 (1.5-1.9), 2.3 (2.0-2.7), respectively). CONCLUSIONS: LDH and ferritin are strongly prognostic in NB, overall and within high-risk NB patients treated post-2009 with modern therapy. LDH and ferritin show promise for (a) identifying ultra-high-risk; (b) refining risk stratification; and (c) clinical utility in low-/middle-income countries. Routine collection of LDH and ferritin should be reinitiated for evolving NB risk stratification.

Biochemical testing for neuroblastoma using plasma free 3-O-methyldopa, 3-methoxytyramine, and normetanephrine.

BACKGROUND: Neuroblastoma, the most common extracranial solid tumor of childhood, produces catecholamines that are metabolized within tumor cells. Homovanillic acid (HVA) and vanillylmandelic acid (VMA), the end products of catecholamine metabolism, have limited accuracy for testing of the tumors. This study assessed whether metabolites produced in earlier steps of catecholamine metabolism might offer improved diagnostic accuracy over urinary HVA and VMA. PROCEDURE: Plasma concentrations of 3-methoxytyramine, normetanephrine, and metanephrine were measured in two pediatric cohorts: (i) 96 children with confirmed neuroblastoma and (ii) 41 children with signs and symptoms of a catecholamine-producing tumor or other neoplasms and in whom neuroblastoma was excluded. Additional measurements of plasma 3-O-methyldopa and relationships of metabolites to MYCN amplification were examined in patient subgroups. RESULTS: Overall, 94 of the 96 patients with neuroblastoma had concentrations of 3-methoxytyramine or normetanephrine above age-specific upper limits of reference intervals, providing a diagnostic sensitivity of 97.9% that was higher (P < 0.0001) than that of 82.2% for HVA and VMA. One of the two patients with normal plasma results showed an elevation of plasma 3-O-methyldopa. Diagnostic specificities were, respectively, 95.1% and 84.8%. Areas under receiver-operating characteristic curves confirmed the superior diagnostic power of the plasma than the urinary test (0.994 vs 0.945; P = 0.0095). Ratios of plasma 3-methoxytyramine to normetanephrine were 7.2-fold higher (P < 0.0001) for patients who had neuroblastomas with MYCN amplification than without MYCN amplification. CONCLUSIONS: Measurements of plasma 3-methoxytyramine and normetanephrine provide a highly accurate diagnostic test for neuroblastoma and also offer potential for prognostic risk stratification.

Correction: Long-term outcomes of the GPOH NB97 trial for children with high-risk neuroblastoma comparing high-dose chemotherapy with autologous stem cell transplantation and oral chemotherapy as consolidation.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

THROMBOTECT - a randomized study comparing low molecular weight heparin, antithrombin and unfractionated heparin for thromboprophylaxis during induction therapy of acute lymphoblastic leukemia in children and adolescents.

Thromboembolism is a serious complication of induction therapy for childhood acute lymphoblastic leukemia. We prospectively compared the efficacy and safety of antithrombotic interventions in the consecutive leukemia trials ALL-BFM 2000 and AIEOP-BFM ALL 2009. Patients with newly diagnosed acute lymphoblastic leukemia (n=949, age 1 to 18 years) were randomized to receive low-dose unfractionated heparin, prophylactic low molecular weight heparin (enoxaparin) or activity-adapted antithrombin throughout induction therapy. The primary objective of the study was to determine whether enoxaparin or antithrombin reduces the incidence of thromboembolism as compared to unfractionated heparin. The principal safety outcome was hemorrhage; leukemia outcome was a secondary endpoint. Thromboembolism occurred in 42 patients (4.4%). Patients assigned to unfractionated heparin had a higher risk of thromboembolism (8.0%) compared with those randomized to enoxaparin (3.5%; P=0.011) or antithrombin (1.9%; P<0.001). The proportion of patients who refused antithrombotic treatment as allocated was 3% in the unfractionated heparin or antithrombin arms, and 33% in the enoxaparin arm. Major hemorrhage occurred in eight patients (no differences between the groups). The 5-year event-free survival was 80.9±2.2% among patients assigned to antithrombin compared to 85.9±2.0% in the unfractionated heparin group (P=0.06), and 86.2±2.0% in the enoxaparin group (P=0.10). In conclusion, prophylactic use of antithrombin or enoxaparin significantly reduced thromboembolism. Despite the considerable number of patients rejecting the assigned treatment with subcutaneous injections, the result remains unambiguous. Thromboprophylaxis - for the present time primarily with enoxaparin - can be recommended for children and adolescents with acute lymphoblastic leukemia during induction therapy. Whether and how antithrombin may affect leukemia outcome remains to be determined.

Long-term outcomes of the GPOH NB97 trial for children with high-risk neuroblastoma comparing high-dose chemotherapy with autologous stem cell transplantation and oral chemotherapy as consolidation.

BACKGROUND: This study was done to investigate the long-term event free and overall survival of high-dose chemotherapy followed by autologous stem cell transplantation (ASCT), compared to maintenance chemotherapy (MT). Patterns of recurrences and late sequelae of both arms were analysed. METHODS: A randomised open label trial was conducted nationwide during 1997-2004 in Germany and Switzerland. 295 patients with high-risk neuroblastoma were randomly assigned to high-dose chemotherapy with autologous stem cell transplantation (ASCT) or maintenance chemotherapy (MT) for consolidation. Analyses were done by intention-to-treat (ITT: ASCT/MT N = 149/146), as treated (AT: N = 110/102), and treated as randomised (TAR: N = 75/70). RESULTS: The event free survival was superior for the patients receiving ASCT compared to patients treated with MT in all three cohorts (hazard ratio [HR] for ITT 1.39, 95% confidence interval (CI) 1.05-1.85, P = 0.022, HR for AT 1.75, CI 1.24-2.47, P = 0.001; HR for TAR 2.07, CI 1.36-3.16, P = 0.001). Overall survival was also in favour of the ASCT groups (ITT: P = 0.075; AT: P = 0.017; TAR: P = 0.005). The frequencies of late sequelae were not different except for focal nodular hyperplasia of the liver observed more frequently in the ASCT arm. CONCLUSIONS: High-dose chemotherapy with autologous stem cell transplantation had a better long-term outcome compared to maintenance chemotherapy.

Recommendations for the standardization of bone marrow disease assessment and reporting in children with neuroblastoma on behalf of the International Neuroblastoma Response Criteria Bone Marrow Working Group.

BACKGROUND: The current study was conducted to expedite international standardized reporting of bone marrow disease in children with neuroblastoma and to improve equivalence of care. METHODS: A multidisciplinary International Neuroblastoma Response Criteria Bone Marrow Working Group was convened by the US National Cancer Institute in January 2012 with representation from Europe, North America, and Australia. Practical transferable recommendations to standardize the reporting of bone marrow disease were developed. RESULTS: To the authors' knowledge, the current study is the first to comprehensively present consensus criteria for the collection, analysis, and reporting of the percentage area of bone marrow parenchyma occupied by tumor cells in trephine-biopsies. The quantitative analysis of neuroblastoma content in bone marrow aspirates by immunocytology and reverse transcriptase-quantitative polymerase chain reaction are revised. The inclusion of paired-like homeobox 2b (PHOX2B) for immunohistochemistry and reverse transcriptase-quantitative polymerase chain reaction is recommended. Recommendations for recording bone marrow response are provided. The authors endorse the quantitative assessment of neuroblastoma cell content in bilateral core needle biopsies-trephines and aspirates in all children with neuroblastoma, with the exception of infants, in whom the evaluation of aspirates alone is advised. It is interesting to note that 5% disease is accepted as an internationally achievable level for disease assessment. CONCLUSIONS: The quantitative assessment of neuroblastoma cells is recommended to provide data from which evidence-based numerical criteria for the reporting of bone marrow response can be realized. This is particularly important in the minimal disease setting and when neuroblastoma detection in bone marrow is intermittent, where clinical impact has yet to be validated. The wide adoption of these harmonized criteria will enhance the ability to compare outcomes from different trials and facilitate collaborative trial design. Cancer 2017;123:1095-1105. © 2016 American Cancer Society.

Complete surgical resection improves outcome in INRG high-risk patients with localized neuroblastoma older than 18 months.

BACKGROUND: Although several studies have been conducted on the role of surgery in localized neuroblastoma, the impact of surgical timing and extent of primary tumor resection on outcome in high-risk patients remains controversial. METHODS: Patients from the German neuroblastoma trial NB97 with localized neuroblastoma INSS stage 1-3 age > 18 months were included for retrospective analysis. Imaging reports were reviewed by two independent physicians for Image Defined Risk Factors (IDRF). Operation notes and corresponding imaging reports were analyzed for surgical radicality. The extent of tumor resection was classified as complete resection (95-100%), gross total resection (90-95%), incomplete resection (50-90%), and biopsy (<50%) and correlated with local control rate and outcome. Patients were stratified according to the International Neuroblastoma Risk Group (INRG) staging system. Survival curves were estimated according to the method of Kaplan and Meier and compared by the log-rank test. RESULTS: A total of 179 patients were included in this study. 77 patients underwent more than one primary tumor operation. After best surgery, 68.7% of patients achieved complete resection of the primary tumor, 16.8% gross total resection, 14.0% incomplete surgery, and 0.5% biopsy only. The cumulative complication rate was 20.3% and the surgery associated mortality rate was 1.1%. Image defined risk factors (IDRF) predicted the extent of resection. Patients with complete resection had a better local-progression-free survival (LPFS), event-free survival (EFS) and OS (overall survival) than the other groups. Subgroup analyses showed better EFS, LPFS and OS for patients with complete resection in INRG high-risk patients. Multivariable analyses revealed resection (complete vs. other), and MYCN (non-amplified vs. amplified) as independent prognostic factors for EFS, LPFS and OS. CONCLUSIONS: In patients with localized neuroblastoma age 18 months or older, especially in INRG high-risk patients harboring MYCN amplification, extended surgery of the primary tumor site improved local control rate and survival with an acceptable risk of complications.

Lack of immunocytological GD2 expression on neuroblastoma cells in bone marrow at diagnosis, during treatment, and at recurrence.

BACKGROUND: Loss of disialoganglioside 2 (GD2) expression in neuroblastoma (NB) bone marrow cells has been reported in rare cases. This study investigated prospectively the frequency and the patterns of visible GD2 loss at diagnosis, during treatment, and at recurrence. METHODS: Bone marrow aspirates of patients with new or recurrent stage 4 and 4S NB diagnosed between January 1, 2002 and August 31, 2013 were investigated in parallel by cytology and GD2 immunocytology. Complete negative immunostaining was defined if staining was absent in all and partial if absent in a portion and/or in case of atypical faint staining. RESULTS: Of 1,261 investigated trial patients of all stages, 474 had unequivocal cytological bone marrow infiltration at initial diagnosis. Thirty-seven patients had tumor cells with complete or partial negative GD2 staining at initial diagnosis, nine during chemotherapy, and 11 at recurrence (altogether 12.0%). The percentage of GD2 negativity in stages 4 and 4S were similar (13% and 9%, respectively). Complete negativity was seen in 14 and partial in 43 cases. Twenty-one cases changed from positive to negative (15 to partial and six to complete) and three cases from negative to positive staining (two to partial and one to complete). The GD2 negative and positive groups were not different regarding tumor sites, molecular characteristics, histology, and tumor markers. Children with stage 4 and GD2 negativity tended to be older at diagnosis (42 vs. 32 months, P = 0.056). Event-free survival and overall survival comparing negative versus positive staining did not show any differences. CONCLUSIONS: Complete or partial lack of GD2 staining on NB cells in bone marrow is more frequent than currently recognized.

Retinoic acid postconsolidation therapy for high-risk neuroblastoma patients treated with autologous haematopoietic stem cell transplantation.

BACKGROUND: Neuroblastoma is a rare malignant disease and mainly affects infants and very young children. The tumours mainly develop in the adrenal medullary tissue, with an abdominal mass as the most common presentation. About 50% of patients have metastatic disease at diagnosis. The high-risk group is characterised by metastasis and other features that increase the risk of an adverse outcome. High-risk patients have a five-year event-free survival of less than 50%. Retinoic acid has been shown to inhibit growth of human neuroblastoma cells and has been considered as a potential candidate for improving the outcome of patients with high-risk neuroblastoma. This review is an update of a previously published Cochrane Review. OBJECTIVES: To evaluate the efficacy and safety of additional retinoic acid as part of a postconsolidation therapy after high-dose chemotherapy (HDCT) followed by autologous haematopoietic stem cell transplantation (HSCT), compared to placebo retinoic acid or to no additional retinoic acid in people with high-risk neuroblastoma (as defined by the International Neuroblastoma Risk Group (INRG) classification system). SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (2016, Issue 11), MEDLINE in PubMed (1946 to 24 November 2016), and Embase in Ovid (1947 to 24 November 2016). Further searches included trial registries (on 22 December 2016), conference proceedings (on 23 March 2017) and reference lists of recent reviews and relevant studies. We did not apply limits by publication year or languages. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating additional retinoic acid after HDCT followed by HSCT for people with high-risk neuroblastoma compared to placebo retinoic acid or to no additional retinoic acid. Primary outcomes were overall survival and treatment-related mortality. Secondary outcomes were progression-free survival, event-free survival, early toxicity, late toxicity, and health-related quality of life. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: The update search did not identify any additional studies. We identified one RCT that included people with high-risk neuroblastoma who received HDCT followed by autologous HSCT (N = 98) after a first random allocation and who received retinoic acid (13-cis-retinoic acid; N = 50) or no further therapy (N = 48) after a second random allocation. These 98 participants had no progressive disease after HDCT followed by autologous HSCT. There was no clear evidence of difference between the treatment groups either in overall survival (hazard ratio (HR) 0.87, 95% confidence interval (CI) 0.46 to 1.63; one trial; P = 0.66) or in event-free survival (HR 0.86, 95% CI 0.50 to 1.49; one trial; P = 0.59). We calculated the HR values using the complete follow-up period of the trial. The study also reported overall survival estimates at a fixed point in time. At the time point of five years, the survival estimate was reported to be 59% for the retinoic acid group and 41% for the no-further-therapy group (P value not reported). We did not identify results for treatment-related mortality, progression-free survival, early or late toxicity, or health-related quality of life. We could not rule out the possible presence of selection bias, performance bias, attrition bias, and other bias. We judged the evidence to be of low quality for overall survival and event-free survival, downgraded because of study limitations and imprecision. AUTHORS' CONCLUSIONS: We identified one RCT that evaluated additional retinoic acid as part of a postconsolidation therapy after HDCT followed by autologous HSCT versus no further therapy in people with high-risk neuroblastoma. There was no clear evidence of a difference in overall survival and event-free survival between the treatment alternatives. This could be the result of low power. Information on other outcomes was not available. This trial was performed in the 1990s, since when many changes in treatment and risk classification have occurred. Based on the currently available evidence, we are therefore uncertain about the effects of retinoic acid in people with high-risk neuroblastoma. More research is needed for a definitive conclusion.

Feasibility, Risk Profile and Diagnostic Yield of Stereotactic Biopsy in Children and Young Adults with Brain Lesions.

Objective To evaluate the feasibility, safety, and diagnostic yield of stereotactic biopsy (SB) in children and adolescents with cerebral lesions. Methods We performed a systematic review of the literature and a retrospective analysis of all pediatric and adolescent patients who underwent SB for unclear brain lesions at our center. We collected patient and lesion-associated parameters, analysed the rate of procedural complications and diagnostic yield. Results Our institutional series consisted of 285 SBs in 269 children and young adults between 1989 and 2016 (median age, 9 (range 1-18) years). There was no procedure-related mortality. Permanent and transient morbidity was 0.7% and 5.8%, respectively. Lesions were located in brain lobes (26.3%) and in midline structures (73.7%). The diagnostic yield was 97.5% and histology consisted low-grade gliomas (44.2%), high-grade gliomas (15.1%), non-glial tumors (22.8%), and non-neoplastic disease (15.4%). Morbidity was not associated with tumor location, age, histology or intraoperative position of the patient. In order to compare our findings with previous reports, we reviewed 25 studies with 1 109 children and young adults which had underwent SB. The diagnostic yield ranged between 83% and 100%. The reported morbidity and mortality rates range from 0-27% and 0-3.3%, respectively. Conclusions SB in this particular patient population is a safe and a high-yield diagnostic procedure and indicates therefore its importance in the light of personalized medicine with the development of individual molecular treatment strategies.