OBJECTIVE:To create the first structured surgical report form for NBL with international consensus, to permit standardized documentation of all NBL-related surgical procedures and their outcomes. SUMMARY OF BACKGROUND DATA:NBL, the most common extracranial solid malignant tumor in children, covers a wide spectrum of tumors with significant differences in anatomical localization, organ or vessel involvement, and tumor biology. Complete surgical resection of the primary tumor is an important part of NBL treatment, but maybe hazardous, prone to complications and its role in high-risk disease remains debated. Various surgical guidelines exist within the protocols of the different cooperative groups, although there is no standardized operative report form to document the surgical treatment of NBL. METHODS:After analyzing the treatment protocols of the SIOP Europe International Neuroblastoma Study Group, Children's Oncology Group, and Gesellschaft fuer Paediatrische Onkologie und Haematologie - German Association of Pediatric Oncology and Haematology pediatric cooperative groups, important variables were defined to completely describe surgical biopsy and resection of NBL and their outcomes. All variables were discussed within the Surgical Committees of SIOP Europe International Neuroblastoma Study Group, Children's Oncology Group, and Gesellschaft fuer Paediatrische Onkologie und Haematologie - German Association of Pediatric Oncology and Haematology. Thereafter, joint meetings were organized to obtain intercontinental consensus. RESULTS:The "International Neuroblastoma Surgical Report Form" provides a structured reporting tool for all NBL surgery, in every anatomical region, documenting all Image Defined Risk Factors and structures involved, with obligatory reporting of intraoperative and 30 day-postoperative complications. CONCLUSION:The International Neuroblastoma Surgical Report Form is the first universal form for the structured and uniform reporting of NBL-related surgical procedures and their outcomes, aiming to facilitate the postoperative communication, treatment planning and analysis of surgical treatment of NBL.

PURPOSE For localized, resectable neuroblastoma without MYCN amplification, surgery only is recommended even if incomplete. However, it is not known whether the genomic background of these tumors may influence outcome. PATIENTS AND METHODS Diagnostic samples were obtained from 317 tumors, International Neuroblastoma Staging System stages 1/2A/2B, from 3 cohorts: Localized Neuroblastoma European Study Group I/II and Children’s Oncology Group. Genomic data were analyzed using multi- and pangenomic techniques and fluorescence in-situ hybridization in 2 age groups (cutoff age, 18 months) and were quality controlled by the International Society of Pediatric Oncology European Neuroblastoma (SIOPEN) Biology Group. RESULTS Patients with stage 1 tumors had an excellent outcome (5-year event-free survival [EFS] ± standard deviation [SD], 95% ± 2%; 5-year overall survival [OS], 99% ± 1%). In contrast, patients with stage 2 tumors had a reduced EFS in both age groups (5-year EFS ± SD, 84% ± 3% in patients < 18 months of age and 75% ± 7% in patients ≥ 18 months of age). However, OS was significantly decreased only in the latter group (5-year OS ± SD in < 18months and ≥ 18months, 96% ± 2% and 81% ± 7%, respectively; P = .001). In < 18months, relapses occurred independent of segmental chromosome aberrations (SCAs); only 1p loss decreased EFS (5-year EFS ± SD in patients 1p loss and no 1p loss, 62% ± 13% and 87% ± 3%, respectively; P = .019) but not OS (5-year OS ± SD, 92% ± 8% and 97% ± 2%, respectively). In patients ≥ 18 months, only SCAs led to relapse and death, with 11q loss as the strongest marker (11q loss and no 11q loss: 5-year EFS ± SD, 48% ± 16% and 85% ± 7%, P = .033; 5-year OS ± SD, 46% ± 22% and 92% ± 6%, P = .038). CONCLUSION Genomic aberrations of resectable non– MYCN-amplified stage 2 neuroblastomas have a distinct age-dependent prognostic impact. Chromosome 1p loss is a risk factor for relapse but not for diminished OS in patients < 18 months, SCAs (especially 11q loss) are risk factors for reduced EFS and OS in those > 18months. In older patients with SCA, a randomized trial of postoperative chemotherapy compared with observation alone may be indicated.

To explore the effects of immunotherapy in the International Society of Paediatric Oncology Europe Neuroblastoma Group SIOPEN high-risk neuroblastoma 1 trial (HR-NBL1 trial), two cohorts were studied: one prior to and one after the introduction of dinutuximab beta. All patients received standard induction and high-dose therapy (HDT) with autologous stem cell rescue (ASCR); the local control comprised surgery and radiotherapy to the primary tumour site, followed by isotretinoin. A landmark timepoint of 109 days, resulting from the median time between ASCR and initiation of immunotherapy, was used to define patients’ eligibility in the pre-immunotherapy analysis cohort. Median follow-up was 5.8 years (inter-quartile range (IQR): 4.2–8.2 years) for 844 eligible patients balanced for risk factors, such as age, sex, stage 4, MYCN amplification and response prior to HDT. The five-year event-free and overall survival (95% confidence interval (CI) of 466 patients not receiving immunotherapy was 42% (38–47%) and 50% (46–55%) but was 57% (51–62%) and 64% (59–69%) for 378 patients receiving immunotherapy (p < 0.001). A multivariate analysis identified absence of immunotherapy (p = 0.0002, hazard ratio (HR) 1.573); type of HDT (p = 0.0029, HR 1.431); less than complete response prior to maintenance therapy (p = 0.0043, HR 1.494) and >1 metastatic compartment at diagnosis (p < 0.001, HR 2.665) as risk factors for relapse or progression. Results suggest an important role for dinutuximab beta-based immunotherapy within the treatment concepts applied in HR-NBL1/SIOPEN.

PURPOSETo evaluate the impact of surgeon-assessed extent of primary tumor resection on local progression and survival in patients in the International Society of Pediatric Oncology Europe Neuroblastoma Group High-Risk Neuroblastoma 1 trial.PATIENTS AND METHODSPatients recruited between 2002 and 2015 with stage 4 disease > 1 year or stage 4/4S with MYCN amplification < 1 year who had completed induction without progression, achieved response criteria for high-dose therapy (HDT), and had no resection before induction were included. Data were collected on the extent of primary tumor excision, severe operative complications, and outcome.RESULTSA total of 1,531 patients were included (median observation time, 6.1 years). Surgeon-assessed extent of resection included complete macroscopic excision (CME) in 1,172 patients (77%) and incomplete macroscopic resection (IME) in 359 (23%). Surgical mortality was 7 (0.46%) of 1,531. Severe operative complications occurred in 142 patients (9.7%), and nephrectomy was performed in 124 (8.8%). Five-year event-free survival (EFS) ± SE (0.40 ± 0.01) and overall survival (OS; 0.45 ± 0.02) were significantly higher with CME compared with IME (5-year EFS, 0.33 ± 0.03; 5-year OS, 0.37 ± 0.03; P < .001 and P = .004). The cumulative incidence of local progression (CILP) was significantly lower after CME (0.17 ± 0.01) compared with IME (0.30 ± 0.02; P < .001). With immunotherapy, outcomes were still superior with CME versus IME (5-year EFS, 0.47 ± 0.02 v 0.39 ± 0.04; P = .038); CILP was 0.14 ± 0.01 after CME and 0.27 ± 0.03 after IME (P < .002). A hazard ratio of 1.3 for EFS associated with IME compared with CME was observed before and after the introduction of immunotherapy (P = .030 and P = .038).CONCLUSIONIn patients with stage 4 high-risk neuroblastoma who have responded to induction therapy, CME of the primary tumor is associated with improved survival and local control after HDT, local radiotherapy (21 Gy), and immunotherapy.

Background Immunotherapy with the chimeric anti-GD2 monoclonal antibody dinutuximab, combined with alternating granulocyte-macrophage colony-stimulating factor and intravenous interleukin-2 (IL-2), improves survival in patients with high-risk neuroblastoma. We aimed to assess event-free survival after treatment with ch14.18/CHO (dinutuximab beta) and subcutaneous IL-2, compared with dinutuximab beta alone in children and young people with high-risk neuroblastoma. Methods We did an international, open-label, phase 3, randomised, controlled trial in patients with high-risk neuroblastoma at 104 institutions in 12 countries. Eligible patients were aged 1-20 years and had MYCN-amplified neuroblastoma with stages 2, 3, or 4S, or stage 4 neuroblastoma of any MYCN status, according to the International Neuroblastoma Staging System. Patients were eligible if they had been enrolled at diagnosis in the HR-NBL1/SIOPEN trial, had completed the multidrug induction regimen (cisplatin, carboplatin, cyclophosphamide, vincristine, and etoposide, with or without topotecan, vincristine, and doxorubicin), had achieved a disease response that fulfilled prespecified criteria, had received high-dose therapy (busulfan and melphalan or carboplatin, etoposide, and melphalan) and had received radiotherapy to the primary tumour site. In this component of the trial, patients were randomly assigned (1:1) to receive dinutuximab beta (20 mg/m(2) per day as an 8 h infusion for 5 consecutive days) or dinutuximab beta plus subcutaneous IL-2 (6 x 10(6) IU/m(2) per day on days 1-5 and days 8-12 of each cycle) with the minimisation method to balance randomisation for national groups and type of high-dose therapy. All participants received oral isotretinoin (160 mg/m(2) per day for 2 weeks) before the first immunotherapy cycle and after each immunotherapy cycle, for six cycles. The primary endpoint was 3-year event-free survival, analysed by intention to treat. This trial was registered with ClinicalTrials.gov, number NCT01704716, and EudraCT, number 2006-001489-17, and recruitment to this randomisation is closed. Findings Between Oct 22, 2009, and Aug 12, 2013, 422 patients were eligible to participate in the immunotherapy randomisation, of whom 406 (96%) were randomly assigned to a treatment group (n=200 to dinutuximab beta and n=206 to dinutuximab beta with subcutaneous IL-2). Median follow-up was 4.7 years (IQR 3.9-5.3). Because of toxicity, 117 (62%) of 188 patients assigned to dinutuximab beta and subcutaneous IL-2 received their allocated treatment, by contrast with 160 (87%) of 183 patients who received dinutuximab beta alone (p<0.0001). 3-year event-free survival was 56% (95% CI 49-63) with dinutuximab beta (83 patients had an event) and 60% (53-66) with dinutuximab beta and subcutaneous IL-2 (80 patients had an event; p=0.76). Four patients died of toxicity (n=2 in each group); one patient in each group while receiving immunotherapy (n=1 congestive heart failure and pulmonary hypertension due to capillary leak syndrome; n=1 infection-related acute respiratory distress syndrome), and one patient in each group after five cycles of immunotherapy (n=1 fungal infection and multi-organ failure; n=1 pulmonary fibrosis). The most common grade 3-4 adverse events were hypersensitivity reactions (19 [10%] of 185 patients in the dinutuximab beta group vs 39 [20%] of 191 patients in the dinutuximab plus subcutaneous IL-2 group), capillary leak (five [4%] of 119 vs 19 [15%] of 125), fever (25 [14%] of 185 vs 76 [40%] of 190), infection (47 [25%] of 185 vs 64 [33%] of 191), immunotherapy-related pain (19 [16%] of 122 vs 32 [26%] of 124), and impaired general condition (30 [16%] of 185 vs 78 [41%] of 192). Interpretation There is no evidence that addition of subcutaneous IL-2 to immunotherapy with dinutuximab beta, given as an 8 h infusion, improved outcomes in patients with high-risk neuroblastoma who had responded to standard induction and consolidation treatment. Subcutaneous IL-2 with dinutuximab beta was associated with greater toxicity than dinutuximab beta alone. Dinutuximab beta and isotretinoin without subcutaneous IL-2 should thus be considered the standard of care until results of ongoing randomised trials using a modified schedule of dinutuximab beta and subcutaneous IL-2 are available. Copyright (c) 2018 Elsevier Ltd. All rights reserved.

10521 Background: The effect of complete macroscopic excision (CME) of the primary tumour on event free survival (EFS) in high-risk neuroblastoma remains controversial. We therefore investigated the influence of CME in patients enrolled on the HR-NBL1/SIOPEN Trial and compared the effect in the pre immunotherapy era. Methods: Eligibility criteria were: inclusion in HR-NBL1/SIOPEN Trial between 2002-2015, stage 4 disease; completion of Rapid COJEC induction ± 2 courses of TVD; no progression/relapse/death; no prior attempt at resection and complete operation data. Intended therapy following operation comprised: HDT/SCT (BuMel or CEM, after 2011 BuMel), 21Gy radiotherapy to the primary site, 13-cis RA and after 2009 ch14.18/CHO antibody ± IL2 in addition. 1504 patients fulfilled these criteria; 737 were treated prior to ch14.18/CHO availability (2002-2009) and 767 in the immunotherapy era. Median observation time was 4.9 years (0.1-14 years). Results: CME was achieved in 77%, incomplete macroscopic excision (IME) in 21% and 2% were inoperable (0E). Surgical mortality was 0.46% (7/1504). Five year event-free survival (5y-EFS ± standard error) was 39%±2% with CME and 30%±3% with IME or 0E (p = 0.002). The cumulative incidence of local relapse (CILR) was 0.17±0.01 (CME); 0.31±0.03 (IME) and 0.42 ±0.10 (0E) (p < 0.001). 88% of patients received radiotherapy (78% CME; 21% IME and 1% 0E). 5y-EFS for patients with CME who received radiotherapy was 44±2%, but 31±6% without (reasons included very young age and very large primary tumours) (p = 0.013) and 35±3% with less than CME compared to 20±1% without radiotherapy (NS). CILR was 0.14±0.01 in patients with CME who received radiotherapy compared to 0.28±0.06 in patients who did not (p = 0.005). 5y-EFS was significantly higher (42±2%) for patients enrolled after 2009 compared to before (32±2%) (p = 0.000). 5-y EFS for patients after 2009 who achieved CME was 45±2% vs. 36±2% after IME and 26±13% after 0E respectively (p = 0.034); compared to 33±2% vs. 26±4% (IME) and 17±11% (0E) (p = 0.059) prior to 2009. Conclusions: In the immunotherapy era, CME in Stage 4 patients who received local radiotherapy resulted in improved 5-EFS. Clinical trial information: NCT01704716.

BACKGROUND:High-dose chemotherapy with haemopoietic stem-cell rescue improves event-free survival in patients with high-risk neuroblastoma; however, which regimen has the greatest patient benefit has not been established. We aimed to assess event-free survival after high-dose chemotherapy with busulfan and melphalan compared with carboplatin, etoposide, and melphalan. METHODS:We did an international, randomised, multi-arm, open-label, phase 3 cooperative group clinical trial of patients with high-risk neuroblastoma at 128 institutions in 18 countries that included an open-label randomised arm in which high-dose chemotherapy regimens were compared. Patients (age 1-20 years) with neuroblastoma were eligible to be randomly assigned if they had completed a multidrug induction regimen (cisplatin, carboplatin, cyclophosphamide, vincristine, and etoposide with or without topotecan, vincristine, and doxorubicin) and achieved an adequate disease response. Patients were randomly assigned (1:1) to busulfan and melphalan or to carboplatin, etoposide, and melphalan by minimisation, balancing age at diagnosis, stage, MYCN amplification, and national cooperative clinical group between groups. The busulfan and melphalan regimen comprised oral busulfan (150 mg/m2 given on 4 days consecutively in four equal doses); after Nov 8, 2007, intravenous busulfan was given (0·8-1·2 mg/kg per dose for 16 doses according to patient weight). After 24 h, an intravenous melphalan dose (140 mg/m2) was given. Doses of busulfan and melphalan were modified according to bodyweight. The carboplatin, etoposide, and melphalan regimen consisted of carboplatin continuous infusion of area under the plasma concentration-time curve 4·1 mg/mL per min per day for 4 days, etoposide continuous infusion of 338 mg/m2 per day for 4 days, and melphalan 70 mg/m2 per day for 3 days, with doses for all three drugs modified according to bodyweight and glomerular filtration rate. Stem-cell rescue was given after the last dose of high-dose chemotherapy, at least 24 h after melphalan in patients who received busulfan and melphalan and at least 72 h after carboplatin etoposide, and melphalan. All patients received subsequent local radiotherapy to the primary tumour site followed by maintenance therapy. The primary endpoint was 3-year event-free survival, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01704716, and EudraCT, number 2006-001489-17. FINDINGS:Between June 24, 2002, and Oct 8, 2010, 1347 patients were enrolled and 676 were eligible for random allocation, 598 (88%) of whom were randomly assigned: 296 to busulfan and melphalan and 302 to carboplatin, etoposide, and melphalan. Median follow-up was 7·2 years (IQR 5·3-9·2). At 3 years, 146 of 296 patients in the busulfan and melphalan group and 188 of 302 in the carboplatin, etoposide, and melphalan group had an event; 3-year event-free survival was 50% (95% CI 45-56) versus 38% (32-43; p=0·0005). Nine patients in the busulfan and melphalan group and 11 in the carboplatin, etoposide, and melphalan group had died without relapse by 5 years. Severe life-threatening toxicities occurred in 13 (4%) patients who received busulfan and melphalan and 29 (10%) who received carboplatin, etoposide, and melphalan. The most frequent grade 3-4 adverse events were general condition (74 [26%] of 281 in the busulfan and melphalan group vs 103 [38%] of 270 in the carboplatin, etoposide, and melphalan group), infection (55 [19%] of 283 vs 74 [27%] of 271), and stomatitis (138 [49%] of 284 vs 162 [59%] of 273); 60 (22%) of 267 patients in the busulfan and melphalan group had Bearman grades 1-3 veno-occlusive disease versus 21 (9%) of 239 in the carboplatin, etoposide, and melphalan group. INTERPRETATION:Busulfan and melphalan improved event-free survival in children with high-risk neuroblastoma with an adequate response to induction treatment and caused fewer severe adverse events than did carboplatin, etoposide, and melphalan. Busulfan and melphalan should thus be considered standard high-dose chemotherapy and ongoing randomised studies will continue to aim to optimise treatment for high-risk neuroblastoma. FUNDING:European Commission 5th Framework Grant and the St Anna Kinderkrebsforschung.

Purpose: To evaluate the impact of image-defined risk factor (IDRF) modification after chemotherapy on surgical outcomes, event-free survival (EFS), and overall survival (OS) among patients enrolled in the European Unresectable Neuroblastoma (EUNB) study. Methods: IDRFs were assigned according to the corresponding surgical risk factors list reported in the database. Surgical outcomes, EFS, and OS were related to IDRF modification with chemotherapy. The predictive value of preoperative IDRF for surgical outcomes was analyzed. Cox proportional hazards models for EFS and OS, including preoperative IDRF, surgical outcomes, and other known clinical risk factors, were created. Results: Of the 160 patients enrolled in the EUNB study, 143 patients met the inclusion criteria. A total of 228 IDRF were thus collected. Following chemotherapy, 76 (33%) IDRF disappeared in 32.2% of patients, 33 (14%) new IDRF appeared in 18.8% of patients, and 49% of patients did not show any IDRF change. Complete resection/minimal residual disease (71.2%) was more frequent among children who had disappearance/numerical reduction of IDRF (P = 0.005). Infiltration of the branches of the mesenteric artery was predictive of an unfavorable surgical outcome. Prolonged preoperative chemotherapy over five courses and encasement of the celiac axis and/or mesenteric artery origin impacted EFS and OS. Conclusions: The unchanged IDRF pattern in 50% of patients and the appearance of new IDRF during chemotherapy in approximately 20% of patients strengthens the idea that prolonged chemotherapy is useless for improving surgical resection in this population of patients. In addition, midline perivascular abdominal preoperative IDRF appeared to be predictive not only of surgical outcomes but also of EFS and OS.

BackgroundThe European multicenter study LNESG1 was designed to evaluate the safety and efficacy of surgical treatment alone in patients with localised neuroblastoma. In a retrospective, observational study we examined the impact of image‐defined risk factors (IDRF) on operative complications and survival (EFS and OS).Procedure534 patients with localised, non‐MYCN amplified neuroblastoma were recruited between 1995 and 1999. Group 1 consisted of 291 patients without IDRF (Stage L1 in the International Neuroblastoma Risk Group (INRG) staging system), all treated with primary surgery. Group 2: 118 patients with IDRF (INRG Stage L2), also treated with primary surgery. Group 3: 125 patients in whom primary surgery was not attempted, 106 receiving neo‐adjuvant chemotherapy.ResultsIn L1 patients (Group 1) 5‐year EFS was 92% and OS 98%. In L2 patients (Group 2 and 3) EFS was 79% and OS 89%. The differences in both EFS and OS were significant. EFS and OS in Group 2 (86% and 95%) were significantly better than 73% and 83% in Group 3. In INSS stage 1, 2 and 3, EFS were respectively 94%, 81% and 76%. Except between stage 2 and 3 the differences were significant. OS were respectively 99%, 93% and 83%, all significantly different. The 17% operative complication rate in L2 patients was significantly higher than 5% in L1 patients.ConclusionsIn localised neuroblastoma, IDRF at diagnosis are associated with worse survival rates and higher rates of operative complications. The impact of IDRF should become an integrated part of therapy planning. Pediatr Blood Cancer 2015;62:1536–1542. © 2015 Wiley Periodicals, Inc.

PURPOSE To evaluate the efficacy of low-dose chemotherapy in infants with nonmetastatic and unresectable neuroblastoma (NB) without MYCN amplification. PATIENTS AND METHODS Infants with localized NB and no MYCN amplification were eligible in the SIOPEN Infant Neuroblastoma European Study 99.1 study. Primary tumor was deemed unresectable according to imaging defined risk factors. Diagnostic procedures and staging were carried out according to International Staging System recommendations. Children without threatening symptoms received low-dose cyclophosphamide (5 mg/kg/d × 5 days) and vincristine (0.05 mg/kg at day 1; CyV), repeated once to three times every 2 weeks until surgical excision could be safely performed. Children with either one threatening symptom or insufficient response to CyV were given carboplatin and etoposide (CaE), sometimes followed by vincristine, cyclophosphamide, and doxorubicin. No postoperative treatment was to be administered. RESULTS Between December 1999 and April 2004, 120 infants were included in the study. Eighty-eight had no threatening symptoms and 79 received CyV. CaE was given to 49 of them because of insufficient response. Thirty-two children had threatening symptoms, 30 of whom received CaE. Anthracyclines were given to 46 children. Surgery was attempted in 102 patients, leading to gross surgical excision in 93. Relapse occurred in 12 patients (nine local and three metastatic). Five-year overall and event-free survivals were 99% ± 1% and 90% ± 3%, respectively, with a median follow-up of 6.1 years (range, 1.6 to 9.1). CONCLUSION Low-dose chemotherapy without anthracyclines is effective in 62% of infants with an unresectable NB and no MYCN amplification, allowing excellent survival rates without jeopardizing their long-term outcome.

BACKGROUND:Anorectal malformations (ARMs) affect 1 in 4000 to 5000 births. The Krickenbeck conference developed a classification based on anatomical and functional criteria to better compare treatment outcome.AIM:The aim of this study is to evaluate the functional outcome in patients 10 years following standardized surgical treatment of ARM related to the Krickenbeck classification. .METHODS:Anatomical anomalies were classified as above. Children and carers were followed closely in a multidisciplinary clinic. Data were collected using a functional outcome questionnaire for a minimum of 10 years after surgical reconstruction. Outcome measurements were related to the Krickenbeck classification.RESULTS:There were 53 children in the study group (29 male, 24 female). Krickenbeck anatomy: perineal fistula, 36%; vestibular fistula, 26%; rectourethral fistula, 36%; rectovesical fistula, 2%. All children were treated by posterior sagittal anorectoplasty. In children with perineal fistula, continence was achieved in 90%. Grade 2 constipation was noted in 21%. One child had a Malone antegrade continence enema (MACE) procedure. In children with vestibular fistula, continence was achieved in 57%. Grade 3 constipation was noted in 28%. One child had grade 1, and one child had grade 2 soiling. Two children had a MACE procedure. In children with rectourethral fistula, continence was achieved in 58%. One child had grade 3 soiling. Grade 3 constipation was found in 42% of children and grade 2 constipation in 1 child. A MACE procedure was performed in 36%. The only child with a bladder neck fistula had a MACE procedure for intractable soiling.CONCLUSIONS:The outcome for patients with ARM is related to the severity of the anomaly. The uniform application of the Krickenbeck classification should allow rational comparison of treatment outcome.

PurposeThe International Neuroblastoma Risk Group (INRG) classification system was developed to establish a consensus approach for pretreatment risk stratification. Because the International Neuroblastoma Staging System (INSS) is a postsurgical staging system, a new clinical staging system was required for the INRG pretreatment risk classification system.MethodsTo stage patients before any treatment, the INRG Task Force, consisting of neuroblastoma experts from Australia/New Zealand, China, Europe, Japan, and North America, developed a new INRG staging system (INRGSS) based on clinical criteria and image-defined risk factors (IDRFs). To investigate the impact of IDRFs on outcome, survival analyses were performed on 661 European patients with INSS stages 1, 2, or 3 disease for whom IDRFs were known.ResultsIn the INGRSS, locoregional tumors are staged L1 or L2 based on the absence or presence of one or more of 20 IDRFs, respectively. Metastatic tumors are defined as stage M, except for stage MS, in which metastases are confined to the skin, liver, and/or bone marrow in children younger than 18 months of age. Within the 661-patient cohort, IDRFs were present (ie, stage L2) in 21% of patients with stage 1, 45% of patients with stage 2, and 94% of patients with stage 3 disease. Patients with INRGSS stage L2 disease had significantly lower 5-year event-free survival than those with INRGSS stage L1 disease (78% +/- 4% v 90% +/- 3%; P = .0010).ConclusionUse of the new staging (INRGSS) and risk classification (INRG) of neuroblastoma will greatly facilitate the comparison of risk-based clinical trials conducted in different regions of the world.

Purpose Although tumor resection is the mainstay of treatment for localized neuroblastoma, there are no established guidelines indicating which patients should be operated on immediately and which should undergo surgery after tumor reduction with chemotherapy. In an effort to develop such guidelines, the LNESG1 study defined surgical risk factors (SRFs) based on the imaging characteristics.Patients and Methods A total of 905 patients with suspected localized neuroblastoma were registered by 10 European countries between January 1995 and October 1999; 811 of 905 patients were eligible for this analysis.Results Information on SRFs was obtained for 719 of 811 patients; 367 without and 352 with SRFs. Of these 719 patients, 201 patients (four without and 197 with SRFs) underwent biopsy only. An attempt at tumor excision was made in 518 patients: 363 of 367 patients without and 155 of 352 patients with SRFs (98.9% v44.0%). Complete excision was achieved in 271 of 363 patients without and in 72 of 155 patients with SRF (74.6% v 46.4%) near-complete excision was achieved in 81 and 61 patients (22.3% v 39.3%), and incomplete excision was achieved in 11 and 22 patients (3.0% v 14.2%), respectively. There were two surgery-related deaths. Nonfatal surgery-related complications occurred in 45 of 518 patients (8.7%) and were less frequent in patients without SRFs (5.0% v 17.4%). Associated surgical procedures were also less frequent in patients without SRFs (1.6% v 9.7%).Conclusion The adoption of SRFs as predictors of adverse surgical outcome was validated because their presence was associated with lower complete resection rate and greater risk of surgery-related complications. Additional studies aiming to better define the surgical approach to localized neuroblastoma are warranted.