PURPOSE: In neuroblastoma (NB), the ALK receptor tyrosine kinase can be constitutively activated through activating point mutations or genomic amplification. We studied ALK genetic alterations in high-risk (HR) patients on the HR-NBL1/SIOPEN trial to determine their frequency, correlation with clinical parameters, and prognostic impact. MATERIALS AND METHODS: Diagnostic tumor samples were available from 1,092 HR-NBL1/SIOPEN patients to determine ALK amplification status (n = 330), ALK mutational profile (n = 191), or both (n = 571). RESULTS: Genomic ALK amplification (ALKa) was detected in 4.5% of cases (41 out of 901), all except one with MYCN amplification (MNA). ALKa was associated with a significantly poorer overall survival (OS) (5-year OS: ALKa [n = 41] 28% [95% CI, 15 to 42]; no-ALKa [n = 860] 51% [95% CI, 47 to 54], [P < .001]), particularly in cases with metastatic disease. ALK mutations (ALKm) were detected at a clonal level (> 20% mutated allele fraction) in 10% of cases (76 out of 762) and at a subclonal level (mutated allele fraction 0.1%-20%) in 3.9% of patients (30 out of 762), with a strong correlation between the presence of ALKm and MNA (P < .001). Among 571 cases with known ALKa and ALKm status, a statistically significant difference in OS was observed between cases with ALKa or clonal ALKm versus subclonal ALKm or no ALK alterations (5-year OS: ALKa [n = 19], 26% [95% CI, 10 to 47], clonal ALKm [n = 65] 33% [95% CI, 21 to 44], subclonal ALKm (n = 22) 48% [95% CI, 26 to 67], and no alteration [n = 465], 51% [95% CI, 46 to 55], respectively; P = .001). Importantly, in a multivariate model, involvement of more than one metastatic compartment (hazard ratio [HR], 2.87; P < .001), ALKa (HR, 2.38; P = .004), and clonal ALKm (HR, 1.77; P = .001) were independent predictors of poor outcome. CONCLUSION: Genetic alterations of ALK (clonal mutations and amplifications) in HR-NB are independent predictors of poorer survival. These data provide a rationale for integration of ALK inhibitors in upfront treatment of HR-NB with ALK alterations.

• MeSH
• amplifikace genu * MeSH
• anaplastická lymfomová kináza genetika   MeSH
• klinické zkoušky, fáze III jako téma MeSH
• kojenec MeSH
• lidé MeSH
• míra přežití MeSH
• mutační rychlost * MeSH
• následné studie MeSH
• neuroblastom genetika   MeSH
• předškolní dítě MeSH
• prognóza MeSH
• protoonkogen n-myc genetika   MeSH
• randomizované kontrolované studie jako téma MeSH
• rizikové faktory MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• anaplastická lymfomová kináza MeSH
• MYCN protein, human MeSH Prohlížeč
• protoonkogen n-myc MeSH

BACKGROUND: In neuroblastoma (NB), the most powerful prognostic marker, the MYCN amplification (MNA), occasionally shows intratumoural heterogeneity (ITH), i.e. coexistence of MYCN-amplified and non-MYCN-amplified tumour cell clones, called heterogeneous MNA (hetMNA). Prognostication and therapy allocation are still unsolved issues. METHODS: The SIOPEN Biology group analysed 99 hetMNA NBs focussing on the prognostic significance of MYCN ITH. RESULTS: Patients <18 months (18 m) showed a better outcome in all stages as compared to older patients (5-year OS in localised stages: <18 m: 0.95 ± 0.04, >18 m: 0.67 ± 0.14, p = 0.011; metastatic: <18 m: 0.76 ± 0.15, >18 m: 0.28 ± 0.09, p = 0.084). The genomic 'background', but not MNA clone sizes, correlated significantly with relapse frequency and OS. No relapses occurred in cases of only numerical chromosomal aberrations. Infiltrated bone marrows and relapse tumour cells mostly displayed no MNA. However, one stage 4s tumour with segmental chromosomal aberrations showed a homogeneous MNA in the relapse. CONCLUSIONS: This study provides a rationale for the necessary distinction between heterogeneous and homogeneous MNA. HetMNA tumours have to be evaluated individually, taking age, stage and, most importantly, genomic background into account to avoid unnecessary upgrading of risk/overtreatment, especially in infants, as well as in order to identify tumours prone to developing homogeneous MNA.

• MeSH
• amplifikace genu * MeSH
• analýza přežití MeSH
• genetická heterogenita MeSH
• kojenec MeSH
• lidé MeSH
• neuroblastom genetika   MeSH
• novorozenec MeSH
• prognóza MeSH
• protoonkogen n-myc genetika   MeSH
• věkové faktory MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• MYCN protein, human MeSH Prohlížeč
• protoonkogen n-myc MeSH

BACKGROUND: Validation of the prognostic value of the SIOPEN mIBG skeletal scoring system in two independent stage 4, mIBG avid, high-risk neuroblastoma populations. RESULTS: The semi-quantitative SIOPEN score evaluates skeletal meta-iodobenzylguanidine (mIBG) uptake on a 0-6 scale in 12 anatomical regions. Evaluable mIBG scans from 216 COG-A3973 and 341 SIOPEN/HR-NBL1 trial patients were reviewed pre- and post-induction chemotherapy. The prognostic value of skeletal scores for 5-year event free survival (5 yr.-EFS) was tested in the source and validation cohorts. At diagnosis, both cohorts showed a gradual non-linear increase in risk with cumulative scores. Several approaches were explored to test the relationship between score and EFS. Ultimately, a cutoff score of ≤3 was the most useful predictor across trials. A SIOPEN score ≤ 3 pre-induction was found in 15% SIOPEN patients and in 22% of COG patients and increased post-induction to 60% in SIOPEN patients and to 73% in COG patients. Baseline 5 yr.-EFS rates in the SIOPEN/HR-NBL1 cohort for scores ≤3 were 47% ± 7% versus 26% ± 3% for higher scores at diagnosis (p < 0.007) and 36% ± 4% versus 14% ± 4% (p < 0.001) for scores obtained post-induction. The COG-A3973 showed 5 yr.-EFS rates for scores ≤3 of 51% ± 7% versus 34% ± 4% for higher scores (p < 0.001) at diagnosis and 43% ± 5% versus 16% ± 6% (p = 0.004) for post-induction scores. Hazard ratios (HR) significantly favoured patients with scores ≤3 after adjustment for age and MYCN-amplification. Optimal outcomes were recorded in patients who achieved complete skeletal response. CONCLUSIONS: Validation in two independent cohorts confirms the prognostic value of the SIOPEN skeletal score. In particular, patients with an absolute SIOPEN score > 3 after induction have very poor outcomes and should be considered for alternative therapeutic strategies.

• Klíčová slova
• High-risk neuroblastoma, MIBG, SIOPEN score,
• MeSH
• 3-jodobenzylguanidin metabolismus   MeSH
• biologický transport MeSH
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• neuroblastom diagnóza   metabolismus   MeSH
• předškolní dítě MeSH
• prognóza MeSH
• riziko MeSH
• společnosti lékařské * MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky MeSH
• validační studie MeSH
• Názvy látek
• 3-jodobenzylguanidin MeSH