Purpose

Survival after neuroblastoma relapse is poor. Understanding the relationship between clinical and biologic features and outcome after relapse may help in selection of optimal therapy. Our aim was to determine which factors were significantly predictive of postrelapse overall survival (OS) in patients with recurrent neuroblastoma—particularly whether time from diagnosis to first relapse (TTFR) was a significant predictor of OS.

Patients and Methods

Patients with first relapse/progression were identified in the International Neuroblastoma Risk Group (INRG) database. Time from study enrollment until first event and OS time starting from first event were calculated. Cox regression models were used to calculate the hazard ratio of increased death risk and perform survival tree regression. TTFR was tested in a multivariable Cox model with other factors.

Results

In the INRG database (N = 8,800), 2,266 patients experienced first progression/relapse. Median time to relapse was 13.2 months (range, 1 day to 11.4 years). Five-year OS from time of first event was 20% (SE, ± 1%). TTFR was statistically significantly associated with OS time in a nonlinear relationship; patients with TTFR of 36 months or longer had the lowest risk of death, followed by patients who relapsed in the period of 0 to less than 6 months or 18 to 36 months. Patients who relapsed between 6 and 18 months after diagnosis had the highest risk of death. TTFR, age, International Neuroblastoma Staging System stage, and MYCN copy number status were independently predictive of postrelapse OS in multivariable analysis.

Conclusion

Age, stage, MYCN status, and TTFR are significant prognostic factors for postrelapse survival and may help in the design of clinical trials evaluating novel agents.

Purpose

Neuroblastomas (NBs) have genomic, biological and clinical heterogeneity. High-risk NBs are characterized by several genomic changes, including MYCN amplification and 1p36 deletion. We identified the chromatin-remodeling gene CHD5 as a tumor suppressor gene that maps to 1p36.31. Low or absent CHD5 expression is associated with a 1p36 deletion and an unfavorable outcome, but the mechanisms of CHD5 inactivation in NBs are unknown.

Experimental Design

We examined 1) the CHD5 sequence in 188 high-risk NBs investigated through the TARGET initiative; 2) the methylation status of the CHD5 promoter in 108 NBs with or without 1p36 deletion and/or MYCN amplification; and 3) mRNA expression of CHD5 and MYCN in 814 representative NBs using TaqMan low-density array microfluidic cards.

Results

We found no examples of somatically acquired CHD5 mutations, even in cases with 1p36 deletion, indicating that homozygous genomic inactivation is rare. Methylation of the CHD5 promoter was common in the high-risk tumors, and it was generally associated with both 1p deletion and MYCN amplification. High CHD5 expression was a powerful predictor of favorable outcome, and it showed prognostic value even in multivariable analysis after adjusting for MYCN amplification, 1p36 deletion, and/or 11q deletion.

Conclusions

We conclude that 1) somatically acquired CHD5 mutations are rare in primary NBs, so inactivation probably occurs by deletion and epigenetic silencing; 2) CHD5 expression and promoter methylation are associated with MYCN amplification, suggesting a possible interaction between these two genes; and 3) high CHD5 expression is strongly correlated with favorable clinical/biological features and outcome.

Purpose

To assess the feasibility of adding dose-intensive topotecan and cyclophosphamide to induction therapy for newly diagnosed high-risk neuroblastoma (HRNB).

Patients and Methods

Enrolled patients received two cycles of topotecan (approximately 1.2 mg/m2/d) and cyclophosphamide (400 mg/m2/d) for 5 days followed by four cycles of multiagent chemotherapy (Memorial Sloan-Kettering Cancer Center [MSKCC] regimen). Pharmacokinetically guided topotecan dosing (target systemic exposure with area under the curve of 50 to 70 ng/mL/hr) was performed. Peripheral-blood stem cell (PBSC) harvest and surgical resection of residual primary tumor occurred after cycles 2 and 5, respectively. Patients achieving at least a partial response received myeloablative chemotherapy with PBSC rescue and radiation to the presurgical primary tumor volume. Oral 13-cis-retinoic acid maintenance therapy was administered twice daily for 14 days in six 28-day cycles.

Results

Thirty-one patients were enrolled onto the study. No deaths related to toxicity or dose-limiting toxicities occurred during induction. Mucositis rarely occurred after topotecan cycles (9.7%) in contrast to 30% after MSKCC cycles. Thirty patients underwent PBSC collection with median 31.1 × 106 CD34+ cells/kg (range, 1.8 to 541.8 × 106 CD34+ cells/kg), all negative for tumor contamination by immunocytochemical analysis. Targeted topotecan systemic exposure was achieved in 26 (84%) of 31 patients. At the end of induction, 26 patients (84%) had tumor response and one patient had progressive disease. In the overall cohort, 3-year event-free and overall survival were 37.8% ± 9.4% and 57.1% ± 9.4%, respectively.

Conclusion

This pilot induction regimen was well tolerated with expected and reversible toxicities. These data support investigation of efficacy in a phase III clinical trial for newly diagnosed HRNB.

Purpose

Patients with neuroblastoma younger than 12 months of age with a 4S pattern of disease (metastases limited to liver, skin, bone marrow) have better outcomes than infants with stage 4 disease. The new International Neuroblastoma Risk Group (INRG) staging system extends age to 18 months for the 4S pattern. Our aim was to determine which prognostic features could be used for optimal risk classification among patients younger than 18 months with metastatic disease.

Methods

Event-free survival (EFS) and overall survival were analyzed by log-rank tests, Cox models, and survival tree regression for 656 infants with stage 4S neuroblastoma younger than 12 months of age and 1,019 patients with stage 4 disease younger than 18 months of age in the INRG database.

Results

Unfavorable biologic features were more frequent in infants with stage 4 disease than in infants with 4S tumors and higher overall in those age 12 to 18 months (although not different for stage 4 v 4S pattern). EFS was significantly better for infants younger than 12 months with 4S pattern than with stage 4 disease (P < .01) but similar for toddlers age 12 to 18 months with stage 4 versus 4S pattern. Among 717 patients with stage 4S pattern, patients age 12 to 18 months had worse EFS than those age younger than 12 months (P < .01). MYCN, 11q, mitosis-karyorrhexis index (MKI), ploidy, and lactate dehydrogenase were independently statistically significant predictors of EFS and more highly predictive than age or metastatic pattern. MYCN, 11q, MKI, histology, and 1p were combined in a survival tree for improved risk stratification.

Conclusion

Tumor biology is more critical than age or metastatic pattern for prognosis of patients age younger than 18 months with metastatic neuroblastoma and should be considered for risk stratification.

Purpose

To determine the response rate to oral capsular fenretinide in children with recurrent or biopsy proven refractory high-risk neuroblastoma.

Experimental Design

Patients received 7 days of fenretinide: 2475 mg/m2/day divided TID (<18 years) or 1800 mg/m2/day divided BID (≥18 years) every 21 days for a maximum of 30 courses. Patients with stable or responding disease after course 30 could request additional compassionate courses. Best response by course 8 was evaluated in Stratum 1 (measurable disease on CT/MRI +/− bone marrow and/or MIBG avid sites) and Stratum 2 (bone marrow and/or MIBG avid sites only).

Results

Sixty-two eligible patients, median age 5 years (range 0.6–19.9), were treated in Stratum 1 (n=38) and Stratum 2 (n=24). One partial response (PR) was seen in Stratum 2 (n=24 evaluable). No responses were seen in Stratum 1 (n=35 evaluable). Prolonged stable disease (SD) was seen in 7 patients in Stratum 1 and 6 patients in Stratum 2 for 4–45+ (median 15) courses. Median time to progression was 40 days (range 17–506) for Stratum 1 and 48 days (range 17–892) for Stratum 2. Mean 4-HPR steady state trough plasma concentrations were 7.25 µM (coefficient of variation 40–56%) at day 7 course 1. Toxicities were mild and reversible.

Conclusions

Although neither stratum met protocol criteria for efficacy, 1 PR + 13 prolonged SD occurred in 14/59 (24%) of evaluable patients. Low bioavailability may have limited fenretinide activity. Novel fenretinide formulations with improved bioavailability are currently in pediatric Phase I studies.

Purpose. 123I-metaiodobenzylguanidine (MIBG) is used for the diagnostic evaluation of neuroblastoma. We evaluated the relationship between norepinephrine transporter (NET) expression and clinical MIBG uptake. Methods. Quantitative reverse transcription PCR (N = 82) and immunohistochemistry (IHC; N = 61) were performed for neuroblastoma NET mRNA and protein expression and correlated with MIBG avidity on diagnostic scans. The correlation of NET expression with clinical features was also performed. Results. Median NET mRNA expression level for the 19 MIBG avid patients was 12.9% (range 1.6–73.7%) versus 5.9% (range 0.6–110.0%) for the 8 nonavid patients (P = 0.31). Median percent NET protein expression was 50% (range 0–100%) in MIBG avid patients compared to 10% (range 0–80%) in nonavid patients (P = 0.027). MYCN amplified tumors had lower NET protein expression compared to nonamplified tumors (10% versus 50%; P = 0.0002). Conclusions. NET protein expression in neuroblastoma correlates with MIBG avidity. MYCN amplified tumors have lower NET protein expression.

Purpose

This phase II study was conducted to determine the response rate associated with use of irinotecan and temozolomide for children with relapsed/refractory neuroblastoma.

Patients and Methods

Patients with relapsed/refractory neuroblastoma measurable by cross-sectional imaging (stratum 1) or assessable by bone marrow aspirate/biopsy or metaiodobenzylguanidine (MIBG) scan (stratum 2) received irinotecan (10 mg/m2/dose 5 days a week for 2 weeks) and temozolomide (100 mg/m2/dose for 5 days) every 3 weeks. Response was assessed after three and six courses using International Neuroblastoma Response Criteria. Of the first 25 evaluable patients on a given stratum, five or more patients with complete or partial responses were required to conclude that further study would be merited.

Results

Fifty-five eligible patients were enrolled. The objective response rate was 15%. Fourteen patients (50%) on stratum 1 and 15 patients (56%) on stratum 2 had stable disease. Objective responses were observed in three of the first 25 evaluable patients on stratum 1 and five of the first 25 evaluable patients on stratum 2. Less than 6% of patients experienced ≥ grade 3 diarrhea. Although neutropenia was observed, less than 10% of patients developed evidence of infection while neutropenic.

Conclusion

The combination of irinotecan and temozolomide was well tolerated. The objective response rate of 19% in stratum 2 suggests that this combination may be effective for patients with neuroblastoma detectable by MIBG or marrow analysis. Although fewer objective responses were observed in patients with disease measurable by computed tomography/magnetic resonance imaging, patients in both strata seem to have derived clinical benefit from this therapy.

Purpose

Although health disparities are well-described for many cancers, little is known about racial and ethnic disparities in neuroblastoma. To evaluate differences in disease presentation and survival by race and ethnicity, data from the Children's Oncology Group (COG) were analyzed.

Patients and Methods

The racial/ethnic differences in clinical and biologic risk factors, and outcome of patients with neuroblastoma enrolled on COG ANBL00B1 between 2001 and 2009 were investigated.

Results

A total of 3,539 patients (white, 72%; black, 12%; Hispanic, 12%; Asian, 4%; and Native American, < 1%) with neuroblastoma were included. The 5-year event-free survival (EFS) rates were 67% for whites (95% CI, 65% to 69%), 69% for Hispanics (95% CI, 63% to 74%), 62% for Asians (95% CI, 51% to 71%), 56% for blacks (95% CI, 50% to 62%), and 37% for Native American (95% CI, 17% to 58%). Blacks (P < .001) and Native Americans (P = .04) had a higher prevalence of high-risk disease than whites, and significantly worse EFS (P = .01 and P = .002, respectively). Adjustment for risk group abrogated these differences. However, closer examination of the EFS among high-risk patients who remained event free for 2 years or longer, revealed a higher prevalence of late-occurring events among blacks compared with whites (hazard ratio, 1.5; 95% CI, 1.0 to 2.3; P = .04).

Conclusion

Black and Native American patients with neuroblastoma have a higher prevalence of high-risk disease, accounting for their worse EFS when compared with whites. The higher prevalence of late-occurring events among blacks with high-risk disease suggests that this population may be more resistant to chemotherapy. Studies focused on delineating the genetic basis for the racial disparities observed in this study are planned.

Purpose

The hu14.18-IL2 fusion protein consists of interleukin-2 molecularly linked to a humanized monoclonal antibody that recognizes the GD2 disialoganglioside expressed on neuroblastoma cells. This phase II study assessed the antitumor activity of hu14.18-IL2 in two strata of patients with recurrent or refractory neuroblastoma.

Patients and Methods

Hu14.18-IL2 was given intravenously (12 mg/m2/daily) for 3 days every 4 weeks for patients with disease measurable by standard radiographic criteria (stratum 1) and for patients with disease evaluable only by [123I]metaiodobenzylguanidine (MIBG) scintigraphy and/or bone marrow (BM) histology (stratum 2). Response was established by independent radiology review as well as BM histology and immunocytology, and durability was assessed by repeat evaluation after more than 3 weeks.

Results

Thirty-nine patients were enrolled (36 evaluable). No responses were seen in stratum 1 (n = 13). Of 23 evaluable patients in stratum 2, five patients (21.7%) responded; all had a complete response (CR) of 9, 13, 20, 30, and 35+ months duration. Grade 3 and 4 nonhematologic toxicities included capillary leak, hypoxia, pain, rash, allergic reaction, elevated transaminases, and hyperbilirubinemia. Two patients required dopamine for hypotension, and one patient required ventilatory support for hypoxia. Most toxicities were reversible within a few days of completing a treatment course and were expected based on phase I results.

Conclusion

Patients with disease evaluable only by MIBG and/or BM histology had a 21.7% CR rate to hu14.8-IL2, whereas patients with bulky disease did not respond. Hu14.18-IL2 warrants further testing in children with nonbulky high-risk neuroblastoma.

Purpose

Single-agent topotecan (TOPO) and combination topotecan and cyclophosphamide (TOPO/CTX) were compared in a phase II randomized trial in relapsed/refractory neuroblastoma. Because responders often underwent further therapies, novel statistical methods were required to compare the long-term outcome of the two treatments.

Patients and Methods

Children with refractory/recurrent neuroblastoma (only one prior aggressive chemotherapy regimen) were randomly assigned to daily 5-day topotecan (2 mg/m2) or combination topotecan (0.75 mg/m2) and cyclophosphamide (250 mg/m2). A randomized two-stage group sequential design enrolled 119 eligible patients. Toxicity and response were estimated. Long-term outcome of protocol therapy was assessed using novel methods—causal inference—which allowed adjustment for the confounding effect of off-study therapies.

Results

Seven more responses were observed for TOPO/CTX (complete response [CR] plus partial response [PR], 18 [32%] of 57) than TOPO (CR+PR, 11 [19%] of 59;P = .081); toxicity was similar. At 3 years, progression-free survival (PFS) and overall survival (OS) were 4% ± 2% and 15% ± 4%, respectively. PFS was significantly better for TOPO/CTX (P = .029); there was no difference in OS. Older age at diagnosis and lack of MYCN amplification predicted increased OS (P < .05). Adjusting for randomized treatment effect and subsequent autologous stem-cell transplantation, there was no difference between TOPO and TOPO/CTX in terms of the proportion alive at 2 years.

Conclusion

TOPO/CTX was superior to TOPO in terms of PFS, but there was no OS difference. After adjustment for subsequent therapies, no difference was detected in the proportion alive at 2 years. Causal inference methods for assessing long-term outcomes of phase II therapies after subsequent treatment can elucidate effects of initial therapies.

Background

Although the prognostic value of the ATP-binding cassette, subfamily C (ABCC) transporters in childhood neuroblastoma is usually attributed to their role in cytotoxic drug efflux, certain observations have suggested that these multidrug transporters might contribute to the malignant phenotype independent of cytotoxic drug efflux.

Methods

A v-myc myelocytomatosis viral related oncogene, neuroblastoma derived (MYCN)–driven transgenic mouse neuroblastoma model was crossed with an Abcc1-deficient mouse strain (658 hMYCN1/−, 205 hMYCN+/1 mice) or, alternatively, treated with the ABCC1 inhibitor, Reversan (n = 20). ABCC genes were suppressed using short interfering RNA or overexpressed by stable transfection in neuroblastoma cell lines BE(2)-C, SH-EP, and SH-SY5Y, which were then assessed for wound closure ability, clonogenic capacity, morphological differentiation, and cell growth. Real-time quantitative polymerase chain reaction was used to examine the clinical significance of ABCC family gene expression in a large prospectively accrued cohort of patients (n = 209) with primary neuroblastomas. Kaplan–Meier survival analysis and Cox regression were used to test for associations with event-free and overall survival. Except where noted, all statistical tests were two-sided.

Results

Inhibition of ABCC1 statistically significantly inhibited neuroblastoma development in hMYCN transgenic mice (mean age for palpable tumor: treated mice, 47.2 days; control mice, 41.9 days; hazard ratio [HR] = 9.3, 95% confidence interval [CI] = 2.65 to 32; P < .001). Suppression of ABCC1 in vitro inhibited wound closure (P < .001) and clonogenicity (P = .006); suppression of ABCC4 enhanced morphological differentiation (P < .001) and inhibited cell growth (P < .001). Analysis of 209 neuroblastoma patient tumors revealed that, in contrast with ABCC1 and ABCC4, low rather than high ABCC3 expression was associated with reduced event-free survival (HR of recurrence or death = 2.4, 95% CI = 1.4 to 4.2; P = .001), with 23 of 53 patients with low ABCC3 expression experiencing recurrence or death compared with 31 of 155 patients with high ABCC3. Moreover, overexpression of ABCC3 in vitro inhibited neuroblastoma cell migration (P < .001) and clonogenicity (P = .03). The combined expression of ABCC1, ABCC3, and ABCC4 was associated with patients having an adverse event, such that of the 12 patients with the “poor prognosis” expression pattern, 10 experienced recurrence or death (HR of recurrence or death = 12.3, 95% CI = 6 to 27; P < .001).

Conclusion

ABCC transporters can affect neuroblastoma biology independently of their role in chemotherapeutic drug efflux, enhancing their potential as targets for therapeutic intervention.

BACKGROUND

Preclinical and preliminary clinical data indicate that ch14.18, a monoclonal antibody against the tumor-associated disialoganglioside GD2, has activity against neuroblastoma and that such activity is enhanced when ch14.18 is combined with granulocyte–macrophage colony-stimulating factor (GM-CSF) or interleukin-2. We conducted a study to determine whether adding ch14.18, GM-CSF, and interleukin-2 to standard isotretinoin therapy after intensive multimodal therapy would improve outcomes in high-risk neuroblastoma.

METHODS

Patients with high-risk neuroblastoma who had a response to induction therapy and stem-cell transplantation were randomly assigned, in a 1:1 ratio, to receive standard therapy (six cycles of isotretinoin) or immunotherapy (six cycles of isotretinoin and five concomitant cycles of ch14.18 in combination with alternating GM-CSF and interleukin-2). Event-free survival and overall survival were compared between the immunotherapy group and the standard-therapy group, on an intention-to-treat basis.

RESULTS

A total of 226 eligible patients were randomly assigned to a treatment group. In the immunotherapy group, a total of 52% of patients had pain of grade 3, 4, or 5, and 23% and 25% of patients had capillary leak syndrome and hypersensitivity reactions, respectively. With 61% of the number of expected events observed, the study met the criteria for early stopping owing to efficacy. The median duration of follow-up was 2.1 years. Immunotherapy was superior to standard therapy with regard to rates of event-free survival (66±5% vs. 46±5% at 2 years, P = 0.01) and overall survival (86±4% vs. 75±5% at 2 years, P = 0.02 without adjustment for interim analyses).

CONCLUSIONS

Immunotherapy with ch14.18, GM-CSF, and interleukin-2 was associated with a significantly improved outcome as compared with standard therapy in patients with high-risk neuroblastoma.

Background

Poor outcome in Stage 4 neuroblastoma may be improved with increased dose intensity of therapy. We investigated the feasibility of sequential collection and infusion of peripheral blood stem cells (PBSC) as hematopoietic support for non-myeloablative dose intensive induction chemotherapy given every 21-28 days.

Methods

Twenty-two children with Stage 4 neuroblastoma (≥ 1yr of age) received 2 cycles of high dose cyclophosphamide (4 gm/m2), doxorubicin (75mg/m2) and vincristine (2mg/m2) followed by 3 cycles of interpatient dose escalating carboplatin (dose level 0 = 800 mg/m2; dose level 1 = 1000 mg/m2), high dose cyclophosphamide (4 gm/m2) and etoposide (600 mg/m2). PBSC were harvested following cycle 2, 3, and 4 in Cohort 1 and infused after each subsequent cycle. In Cohort 2, PBSC were harvested after cycle 2 and split into 3 aliquots for infusion. Dose limiting toxicity (DLT) and ability to administer cycles within 28 days was assessed.

Results

Sufficient PBSC (≥ 2 × 106 CD34 cells/kg per infusion) were collected from 17/21 eligible patients with minimal toxicity and no detectable neuroblastoma cells by immunocytology. Carboplatin at 1000 mg/m2 resulted in DLT of delayed platelet recovery > 28 days in 4/8 patients. Despite de-escalation to 800 mg/m2, platelet DLT occurred in 4/7 Cohort 1 and 3/7 Cohort 2 patients.

Conclusion

As defined in this protocol, doses of carboplatin were not tolerable with the PBSC dose administered. However, it was feasible to collect sufficient PBSC from small neuroblastoma patients to use as hematopoietic support with minimal risk of tumor contamination and toxicity.

BACKGROUND

The survival rate among patients with intermediate-risk neuroblastoma who receive dose-intensive chemotherapy is excellent, but the survival rate among patients who receive reduced doses of chemotherapy for shorter periods of time is not known.

METHODS

We conducted a prospective, phase 3, nonrandomized trial to determine whether a 3-year estimated overall survival of more than 90% could be maintained with reductions in the duration of therapy and drug doses, using a tumor biology-based therapy assignment. Eligible patients had newly diagnosed, intermediate-risk neuroblastoma without MYCN amplification; these patients included infants (<365 days of age) who had stage 3 or 4 disease, children (≥365 days of age) who had stage 3 tumors with favorable histopathological features, and infants who had stage 4S disease with a diploid DNA index or unfavorable histopathological features. Patients who had disease with favorable histopathological features and hyperdiploidy were assigned to four cycles of chemotherapy, and those with an incomplete response or either unfavorable feature were assigned to eight cycles.

RESULTS

Between 1997 and 2005, a total of 479 eligible patients were enrolled in this trial (270 patients with stage 3 disease, 178 with stage 4 disease, and 31 with stage 4S disease). A total of 323 patients had tumors with favorable biologic features, and 141 had tumors with unfavorable biologic features. Ploidy, but not histopathological features, was significantly predictive of the outcome. Severe adverse events without disease progression occurred in 10 patients (2.1%), including secondary leukemia (in 3 patients), death from infection (in 3 patients), and death at surgery (in 4 patients). The 3-year estimate (±SE) of overall survival for the entire group was 96±1%, with an overall survival rate of 98±1% among patients who had tumors with favorable biologic features and 93±2% among patients who had tumors with unfavorable biologic features.

CONCLUSIONS

A very high rate of survival among patients with intermediate-risk neuroblastoma was achieved with a biologically based treatment assignment involving a substantially reduced duration of chemotherapy and reduced doses of chemotherapeutic agents as compared with the regimens used in earlier trials. These data provide support for further reduction in chemotherapy with more refined risk stratification. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00003093.)

The Children’s Oncology Group (COG) is a National Cancer Institute sponsored cooperative clinical trials group with the primary mission of conducting pediatric cancer clinical trials. COG has complex risk classification systems that are used to deliver risk-stratified therapy for many pediatric cances, including clinical trials for Acute Lymphoblastic Leukemia (ALL) and Neuroblastoma (NB). Classification of patients is based on biological, clinical, and genomic data obtained at initial diagnosis and during the initial phases of therapy. The COG web-based remote data entry (RDE) system enables submission of data in real time from central laboratories and treating institutions. The data are then used in an automated fashion to determine the risk group and corresponding treatment assignment for individual patients enrolled in COG clinical trials.

Background

The International Neuroblastoma Pathology Classification (INPC) was the first to clearly define prognostic subgroups in ganglioneuroma (GN) and ganglioneuroblastoma (GNB).

Procedure

Histopathology and tumor resectability of 552 GN/GNB cases from the CCG (Children’s Cancer Group) and COG (Children’s Oncology Group) neuroblastoma studies were reviewed. The results were analyzed along with clinical information and biological data of the cases.

Results

According to the INPC, 300 tumors were classified into the Favorable Histology (FH) group and 252 were into the Unfavorable Histology (UH) group. Tumors in the FH group included 43 ganglioneuroma-maturing (GN-M), 198 ganglioneuroblastoma-intermixed (GNB-I), and 59 ganglioneuroblastoma-nodular, favorable subset (GNB-N-FS), and were often (91%) resected completely by single or multiple surgical procedures. Patients with the FH tumors had an excellent prognosis with no tumor-related deaths. The UH group included ganglioneuroblastoma-nodular, unfavorable subset (GNB-N-US) tumors. Patients with the UH tumors had a high incidence (53%) of distant metastasis at the time of diagnosis, and their prognosis significantly depended on clinical stage (5-year EFS: 80.1% for non-stage 4 patients; 16.7% for stage 4 patients): Complete primary tumor resection was not beneficial to those GNB-N-US patients, regardless of whether metastasis was present or not. MYCN amplification was detected in 4 tumors in the FH group and 6 tumors in the UH group. The majority (160/191, 84%) of GN-M and GNB-I tumors had a diploid pattern determined by flow cytometry.

Conclusions

Stringent application of the INPC along with clinical staging was critical for prognostic evaluation of the patients with this group of tumors.

Background

MYCN oncogene amplification has been defined as the most important prognostic factor for neuroblastoma, the most common solid extracranial neoplasm in children. High copy numbers are strongly associated with rapid tumor progression and poor outcome, independently of tumor stage or patient age, and this has become an important factor in treatment stratification.

Procedure

By Real Time Quantitative PCR analysis, we evaluated the clinical relevance of circulating MYCN DNA of 267 patients with locoregional or metastatic neuroblastoma in children less than 18 months of age.

Results

For patients in this age group with INSS stage 4 or 4S NB and stage 3 patients, serum-based determination of MYCN DNA sequences had good sensitivity (85%, 83% and 75% respectively) and high specificity (100%) when compared to direct tumor gene determination. In contrast, the approach showed low sensitivity patients with stage 1 and 2 disease.

Conclusion

Our results show that the sensitivity of the serum-based MYCN DNA sequence determination depends on the stage of the disease. However, this simple, reproducible assay may represent a reasonably sensitive and very specific tool to assess tumor MYCN status in cases with stage 3 and metastatic disease for whom a wait and see strategy is often recommended.

Purpose

Neuroblastoma is a childhood cancer of the sympathetic nervous system and many patients present with high risk disease. Risk stratification, based on pathology and tumor-derived biomarkers, has improved prediction of clinical outcomes, but overall survival rates remain unfavorable and new therapeutic targets are needed. Some studies suggest a link between interleukin-6 and more aggressive behavior in neuroblastoma tumor cells. Therefore, we examined the impact of two IL-6 single nucleotide polymorphisms (SNP) on neuroblastoma disease progression.

Experimental design

DNA samples from 96 high risk neuroblastoma patients were screened for two SNP that are known to regulate the serum levels of IL-6 and the soluble IL-6 receptor (IL-6R), rs1800795 and rs8192284 respectively. The genotype for each SNP was determined in a blinded fashion and independent statistical analysis was performed to determine SNP-related event free survival (EFS) and overall survival (OS) rates.

Results

The rs1800795 IL-6 promoter SNP is an independent prognostic factor for EFS and OS in -high risk neuroblastoma patients. In contrast, the rs8192284 IL-6 receptor SNP revealed no prognostic value.

Conclusions

The rs1800795 SNP (-174 IL-6 (G>C) represents a novel and independent prognostic marker for both EFS and OS in high risk neuroblastoma. Since the rs1800795 SNP (-174 IL-6 (G>C) has been shown to correlate with production of IL-6, this cytokine may represent a target for development of new therapies in neuroblastoma.

Purpose

We assessed the long-term outcome of patients enrolled on CCG-3891, a high-risk neuroblastoma study in which patients were randomly assigned to undergo autologous purged bone marrow transplantation (ABMT) or to receive chemotherapy, and subsequent treatment with 13-cis-retinoic acid (cis-RA).

Patients and Methods

Patients received the same induction chemotherapy, with random assignment (N = 379) to consolidation with myeloablative chemotherapy, total-body irradiation, and ABMT versus three cycles of intensive chemotherapy. Patients who completed consolidation without disease progression were randomly assigned to receive no further therapy or cis-RA for 6 months.

Results

The event-free survival (EFS) for patients randomly assigned to ABMT was significantly higher than those randomly assigned to chemotherapy; the 5-year EFS (mean ± SE) was 30% ± 4% versus 19% ± 3%, respectively (P = .04). The 5-year EFS (42% ± 5% v 31% ± 5%) from the time of second random assignment was higher for cis-RA than for no further therapy, though it was not significant. Overall survival (OS) was significantly higher for each random assignment by a test of the log(−log(.)) transformation of the survival estimates at 5 years (P < .01). The 5-year OS from the second random assignment of patients who underwent both random assignments and who were assigned to ABMT/cis-RA was 59% ± 8%; for ABMT/no cis-RA, it was 41% ± 7%; for continuing chemotherapy/cis-RA, it was 38% ± 7%; and for chemotherapy/no cis-RA, it was 36% ± 7%.

Conclusion

Myeloablative therapy and autologous hematopoietic cell rescue result in significantly better 5-year EFS and OS than nonmyeloablative chemotherapy; cis-RA given after consolidation independently results in significantly improved OS.

Purpose

Treatment of patients with localized neuroblastoma with unfavorable biologic features is controversial. To evaluate the outcome of children with low-stage MYCN-amplified neuroblastoma and develop a rational treatment strategy, data from the International Neuroblastoma Risk Group (INRG) database were analyzed.

Patients and Methods

The database is comprised of 8,800 patients. Of these, 2,660 patients (30%) had low-stage (International Neuroblastoma Staging System stages 1 and 2) neuroblastoma, known MYCN status, and available follow-up data. Eighty-seven of these patients (3%) had MYCN amplified tumors.

Results

Patients with MYCN-amplified, low-stage tumors had less favorable event-free survival (EFS) and overall survival (OS) than did patients with nonamplified tumors (53% ± 8% and 72% ± 7% v 90% ± 1% and 98% ± 1%, respectively). EFS and OS were statistically significantly higher for patients whose tumors were hyperdiploid rather than diploid (EFS, 82% ± 20% v 37% ± 21%; P = .0069; OS, 94% ± 11% v 54% ± 15%; P = .0056, respectively). No other variable had prognostic significance. Initial treatment consisted of surgery alone for 29 (33%) of 87 patients. Details of additional therapy were unknown for 14 patients. Twenty-two patients (25%) underwent surgery and moderate-intensity chemotherapy; another 22 underwent surgery, intensive chemotherapy, and radiation therapy. Nine of the latter 22 underwent stem cell transplantation. Survival in patients who received transplantation did not differ from survival in those who did not receive transplantation.

Conclusion

Among patients with low-stage, MYCN-amplified neuroblastoma, outcomes of patients with hyperdiploid tumors were statistically, significantly better than those with diploid tumors. The data suggest that tumor cell ploidy could potentially be used to identify candidates for reductions in therapy. Further study of MYCN-amplified, low-stage neuroblastoma is warranted.

Purpose

The 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.

Methods

To 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.

Results

In 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).

Conclusion

Use 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

Because current approaches to risk classification and treatment stratification for children with neuroblastoma (NB) vary greatly throughout the world, it is difficult to directly compare risk-based clinical trials. The International Neuroblastoma Risk Group (INRG) classification system was developed to establish a consensus approach for pretreatment risk stratification.

Patients and Methods

The statistical and clinical significance of 13 potential prognostic factors were analyzed in a cohort of 8,800 children diagnosed with NB between 1990 and 2002 from North America and Australia (Children's Oncology Group), Europe (International Society of Pediatric Oncology Europe Neuroblastoma Group and German Pediatric Oncology and Hematology Group), and Japan. Survival tree regression analyses using event-free survival (EFS) as the primary end point were performed to test the prognostic significance of the 13 factors.

Results

Stage, age, histologic category, grade of tumor differentiation, the status of the MYCN oncogene, chromosome 11q status, and DNA ploidy were the most highly statistically significant and clinically relevant factors. A new staging system (INRG Staging System) based on clinical criteria and tumor imaging was developed for the INRG Classification System. The optimal age cutoff was determined to be between 15 and 19 months, and 18 months was selected for the classification system. Sixteen pretreatment groups were defined on the basis of clinical criteria and statistically significantly different EFS of the cohort stratified by the INRG criteria. Patients with 5-year EFS more than 85%, more than 75% to ≤ 85%, ≥ 50% to ≤ 75%, or less than 50% were classified as very low risk, low risk, intermediate risk, or high risk, respectively.

Conclusion

By defining homogenous pretreatment patient cohorts, the INRG classification system will greatly facilitate the comparison of risk-based clinical trials conducted in different regions of the world and the development of international collaborative studies.

We conducted a SNP-based genome-wide association study (GWAS) focused on the high-risk subset of neuroblastoma1. As our previous unbiased GWAS showed strong association of common 6p22 SNP alleles with aggressive neuroblastoma2, we now restricted our analysis to 397 high-risk cases compared to 2,043 controls. We detected new significant association of six SNPs at 2q35 within the BARD1 gene locus (Pallelic = 2.35×10−9 − 2.25×10−8). Each SNP association was confirmed in a second series of 189 high-risk cases and 1,178 controls (Pallelic = 7.90×10−7 − 2.77×10−4). The two most significant SNPs (rs6435862, rs3768716) were also tested in two additional independent high-risk neuroblastoma case series, yielding combined allelic odds-ratios of 1.68 each (P = 8.65×10−18 and 2.74×10−16, respectively). Significant association was also found with known BARD1 nsSNPs. These data show that common variation in BARD1 contributes to the etiology of the aggressive and most clinically relevant subset of human neuroblastoma.

Neuroblastoma is a frequently lethal childhood tumor in which MYC gene deregulation, commonly as MYCN amplification, portends poor outcome. Identifying the requisite biopathways downstream of MYC may provide therapeutic opportunities. We used transcriptome analyses to show that MYCN-amplified neuroblastomas have co-ordinately deregulated myriad polyamine enzymes (including ODC1, SRM, SMS, AMD1, OAZ2, and SMOX) to enhance polyamine biosynthesis. High-risk tumors without MYCN amplification also overexpress ODC1, the rate-limiting enzyme in polyamine biosynthesis, when compared with lower risk tumors, suggesting this pathway may be pivotal. Indeed, elevated ODC1 (independent of MYCN amplification) was associated with reduced survival in a large independent neuroblastoma cohort. As polyamines are essential for cell survival and linked to cancer progression, we studied polyamine antagonism to test for metabolic dependence on this pathway in neuroblastoma. The Odc inhibitor α-difluoromethylornithine (DFMO) inhibited neuroblast proliferation in vitro and suppressed oncogenesis in vivo. DFMO treatment of neuroblastoma-prone genetically-engineered mice (TH-MYCN GEM) extended tumor latency and survival in homozygous mice, and prevented oncogenesis in hemizygous mice. In the latter, transient Odc ablation permanently prevented tumor onset consistent with a time-limited window for embryonal tumor initiation. Importantly, we show that DFMO augments anti-tumor efficacy of conventional cytotoxics in vivo. This work implicates polyamine biosynthesis as an arbiter of MYCN oncogenesis and demonstrates initial efficacy for polyamine depletion strategies in neuroblastoma, a strategy that may have utility for this and other MYC-driven embryonal tumors.

Background

Neuroblastoma is the most common extracranial pediatric solid cancer. Lung metastasis is rarely detected in children with newly diagnosed neuroblastoma. We aimed to describe the incidence, clinical characteristics, and outcome of patients with lung metastasis at initial diagnosis using a large international database.

Procedure

The subset of patients from the International Neuroblastoma Risk Group database with INSS stage 4 neuroblastoma and known data regarding lung metastasis at diagnosis was selected for analysis. Clinical and biological characteristics were compared between patients with and without lung metastasis. Survival for patients with and without lung metastasis was estimated by Kaplan-Meier methods. Cox proportional hazards methods were used to determine the independent prognostic value of lung metastasis at diagnosis.

Results

Of the 2,808 patients with INSS stage 4 neuroblastoma diagnosed between 1990 and 2002, 100 patients (3.6%) were reported to have lung metastasis at diagnosis. Lung metastasis was more common among patients with MYCN amplified tumors, adrenal primary tumors, or elevated lactate dehydrogenase (LDH) levels (p < 0.02 in each case). Five-year overall survival ± standard error for patients with lung metastasis was 34.5% ± 6.8% compared to 44.7% ± 1.3% for patients without lung metastasis (p=0.0002). However, in multivariable analysis, the presence of lung metastasis was not independently predictive of outcome.

Conclusions

Lung metastasis at initial diagnosis of neuroblastoma is associated with MYCN amplification and elevated LDH levels. Although lung metastasis at diagnosis was not independently predictive of outcome in this analysis, it remains a useful prognostic marker of unfavorable outcome.