Phase I Study of Vorinostat as a Radiation Sensitizer with 131I-Metaiodobenzylguanidine (131I-MIBG) for Patients with Relapsed or Refractory Neuroblastoma

PURPOSE

(131)I-metaiodobenzylguanidine (MIBG) is a radiopharmaceutical with activity in neuroblastoma. Vorinostat is a histone deacetylase inhibitor that has radiosensitizing properties. The goal of this phase I study was to determine the MTDs of vorinostat and MIBG in combination.

EXPERIMENTAL DESIGN

Patients ≤ 30 years with relapsed/refractory MIBG-avid neuroblastoma were eligible. Patients received oral vorinostat (dose levels 180 and 230 mg/m(2)) daily days 1 to 14. MIBG (dose levels 8, 12, 15, and 18 mCi/kg) was given on day 3 and peripheral blood stem cells on day 17. Alternating dose escalation of vorinostat and MIBG was performed using a 3+3 design.

RESULTS

Twenty-seven patients enrolled to six dose levels, with 23 evaluable for dose escalation. No dose-limiting toxicities (DLT) were seen in the first three dose levels. At dose level 4 (15 mCi/kg MIBG/230 mg/m(2) vorinostat), 1 of 6 patients had DLT with grade 4 hypokalemia. At dose level 5 (18 mCi/kg MIBG/230 mg/m(2) vorinostat), 2 patients had dose-limiting bleeding (one grade 3 and one grade 5). At dose level 5a (18 mCi/kg MIBG/180 mg/m(2) vorinostat), 0 of 6 patients had DLT. The most common toxicities were neutropenia and thrombocytopenia. The response rate was 12% across all dose levels and 17% at dose level 5a. Histone acetylation increased from baseline in peripheral blood mononuclear cells collected on days 3 and 12 to 14.

CONCLUSIONS

Vorinostat at 180 mg/m(2)/dose is tolerable with 18 mCi/kg MIBG. A phase II trial comparing this regimen to single-agent MIBG is ongoing.

Second malignancies in patients with neuroblastoma: the effects of risk-based therapy

BACKGROUND

To investigate the incidence of second malignant neoplasms (SMN) for patients with neuroblastoma, we analyzed patients from the SEER database according to three treatment eras (Era 1: 1973-1989, Era 2: 1990-1996, and Era 3: 1997-2006) corresponding to the introduction of multi-agent chemotherapy, risk-based treatment, and stem cell transplant.

PROCEDURES

The SEER database was mined for all patients with neuroblastoma or ganglioneuroblastoma. Cumulative incidence of SMN was calculated with death as a competing risk. A poisson regression model was used to estimate incidence rate ratios and 95% confidence intervals to compare the rates of SMN between patients in different Eras.

RESULTS

The analytic cohort included 2,801 patients. Thirty-four patients developed a SMN, accounting for 1.2% of all patients. Of the patients who developed a SMN, 47.1% received radiation for their primary neuroblastoma. Fourteen of the SMN were carcinomas, and 10 were hematologic malignancies, with six cases of acute myelogenous leukemia. There was no difference in the incidence of SMN in Era 1 compared to Era 3 (P = 0.48). The cumulative incidence of SMN at 30 years for high-risk patients was 10.44% (95% CI 3.98-20.52%) compared to 3.57% (95% CI 1.87-6.12%) for non-high-risk patients (P < 0.001).

CONCLUSIONS

This study showed no increase in the incidence of SMNs for children treated in the most recent treatment era as compared to earlier Eras. However, as the risk for developing SMN does not plateau, the number of SMNs will likely continue to rise in the cohort of patients treated after 1996. Comprehensive follow-up care for these survivors will be important.

Significance of clinical and biologic features in Stage 3 neuroblastoma: a report from the International Neuroblastoma Risk Group project

BACKGROUND

International Neuroblastoma Staging System (INSS) Stage 3 neuroblastoma is a heterogeneous disease. Data from the International Neuroblastoma Risk Group (INRG) database were analyzed to define patient and tumor characteristics predictive of outcome.

PROCEDURE

Of 8,800 patients in the INRG database, 1,483 with INSS Stage 3 neuroblastoma and complete follow-up data were analyzed. Secondary analysis was performed in 1,013 patients (68%) with MYCN-non-amplified (NA) tumors. Significant prognostic factors were identified via log-rank test comparisons of survival curves. Multivariable Cox proportional hazards regression model was used to identify factors independently predictive of event-free survival (EFS).

RESULTS

Age at diagnosis (P < 0.0001), tumor MYCN status (P < 0.0001), and poorly differentiating/undifferentiated histology (P = 0.03) were independent predictors of EFS. Compared to other Stage 3 subgroups, outcome was inferior for patients ≥ 547 days with MYCN-NA neuroblastoma (P < 0.0001), and within this cohort, serum ferritin ≥ 96 ng/ml was associated with inferior EFS (P = 0.02). For patients <547 days of age with MYCN-NA tumors, serum ferritin levels were prognostic of overall survival (OS) (P = 0.04) and chromosome 11q aberration was prognostic of EFS (P = 0.03).

CONCLUSIONS

Among patients with INSS Stage 3 neuroblastoma patients, age at diagnosis, MYCN status and histology predict outcome. Patients <547 days of age with MYCN-NA tumors that lack chromosome 11q aberrations or those with serum ferritin <96 ng/ml have excellent prognosis and should be considered for therapy reduction. Prospective clinical trials are needed to identify optimal therapy for those patients ≥ 547 days of age with undifferentiated histology or elevated serum ferritin.

Abstract B40: MYCN/MYC protein expression in high-MKI (Mitosis-Karyorrhexis Index) neuroblastomas: A report from the Children's Oncology Group

Background: In neuroblastoma (NB), Mitosis-Karyorrhexis Index (MKI; low-L, &lt;100/5,000 cells; intermediate-I, 100-200/5,000 cells; high-H, &gt;200/5,000 cells) is one of the histologic indicators for predicting a patient's clinical outcome. Event-Free Survival (EFS) and Overall Survival (OS) are significantly worse as MKI increases (p&lt;0.0001): 3-year EFS for L-MKI (81.2+1.0%), I-MKI (68.6+1.8%), H-MKI (51.0+2.2%); and 3-year OS for L-MKI (92.0+0.7%), I-MKI (81.0+1.6%), H-MKI (64.4+2.1%). MYCN amplification (MYCN-A) is significantly associated with H-MKI, which indicates markedly increased mitotic (cellular proliferation) and karyorrhectic (cellular death) cells. However, about one-third of H-MKI tumors do not have MYCN-A.

Study design: A total of 4,712 NB cases reviewed by the Children's Oncology Group (COG) Neuroblastoma Pathology Reference Laboratory (Children's Hospital Los Angeles) between 06/18/2001 and 06/06/2013 included 2,595 L-MKI (3% with MYCN-A), 1,197 I-MKI (16% with MYCN-A), and 920 H-MKI (70% with MYCN-A) tumors. In this study, immunohistochemical detection of MYCN and MYC (C-myc) protein was performed on 82 H-MKI tumors (53 with MYCN-A and 29 without MYCN-A).

Results: 50/53 (94%) of H-MKI tumors having MYCN-A were positive for MYCN protein (including one case positive for both MYCN and MYC proteins), and only 3 cases were negative for both proteins immunohistochemically. Among the H-MKI tumors without MYCN-A, 16 cases (55%) showed positive staining for MYC protein, 6 cases (21%) were positive for MYCN protein, 2 cases (7%) were positive for both proteins, and 5 cases (17%) were negative for both proteins.

Conclusions: MYCN-A and subsequent MYCN protein expression are considered as the starting point for leading NB tumors to H-MKI status. However, when MYCN is not amplified, high mitotic/karyorrhectic (M/K) activities in NB tumors are often associated with MYC protein expression. Even some MYCN non-amplified tumors can express MYCN protein, which is associated with H-MKI. There is still a small group of H-MKI tumors whose increased M/K activities are not related to MYCN/MYC protein expression.

Citation Format: Larry L. Wang, Risa Teshiba, Lejian He, Arlene Naranjo, Wendy B. London, Julie M. Gastier-Foster, Robert C. Seeger, Susan L. Cohn, John M. Maris, Julie R. Park, Michael D. Hogarty, Hiroyuki Shimada. MYCN/MYC protein expression in high-MKI (Mitosis-Karyorrhexis Index) neuroblastomas: A report from the Children's Oncology Group. [abstract]. In: Proceedings of the AACR Special Conference on Pediatric Cancer at the Crossroads: Translating Discovery into Improved Outcomes; Nov 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;74(20 Suppl):Abstract nr B40.

Abstract 3607: Modulation of neuroblastoma metabolism by an extracellular chaperone SPARC

Secreted Protein Acidic and Rich in Cysteine (SPARC) is an extracellular matrix protein with diverse biologic functions. We have shown that SPARC is a scavenger chaperone that regulates matrix degradation, remodeling, and repair. We have also demonstrated that SPARC blocks angiogenesis and inhibits the growth of several cancers, including neuroblastoma. In this study we examined how extracellular chaperone SPARC affects neuroblastoma tumor progression.

The chaperone properties of SPARC were characterized with cell biology methods and Surface Plasmon Resonance. Neuroblastoma cell lines derived from the high-risk tumors were treated with SPARC. The effect of SPARC on cancer cell metabolism was characterized using the Seahorse analyzer with and without inhibitors of glycolysis and mitochondrial oxidation. Standard cell culture techniques were used to assess the effect of SPARC-induced metabolic changes on neuroblastoma cell proliferation and survival.

We demonstrate that SPARC functions as a chaperone, shuttling extracellular ligands between cellular and extracellular tissue compartments. We characterize physical and biological properties of SPARC-mediated ligand transport, and further demonstrate that as a chaperone, SPARC can significantly affect tissue physiology, to the degree of altering cell metabolism. We show that in addition to inhibition of neuroblastoma progression in vivo, SPARC-induced changes in cellular metabolism severely impair neuroblastoma growth and survival in vitro.

This novel mechanism of metabolism regulation by an extracellular chaperone SPARC may lead to additional insights into the therapy of neuroblastoma.

Citation Format: Alexandre Chlenski, Marija Dobratic, Helen R. Salwen, Mark Applebaum, Susan L. Cohn. Modulation of neuroblastoma metabolism by an extracellular chaperone SPARC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3607. doi:10.1158/1538-7445.AM2014-3607

Clinical, biologic, and prognostic differences on the basis of primary tumor site in neuroblastoma: a report from the international neuroblastoma risk group project

PURPOSE

Neuroblastoma (NB) is a heterogeneous tumor arising from sympathetic tissues. The impact of primary tumor site in influencing the heterogeneity of NB remains unclear.

PATIENTS AND METHODS

Children younger than age 21 years diagnosed with NB or ganglioneuroblastoma between 1990 and 2002 and with known primary site were identified from the International Neuroblastoma Risk Group database. Data were compared between sites with respect to clinical and biologic features, as well as event-free survival (EFS) and overall survival (OS).

RESULTS

Among 8,369 children, 47% had adrenal tumors. All evaluated clinical and biologic variables differed statistically between primary sites. The features that were > 10% discrepant between sites were stage 4 disease, MYCN amplification, elevated ferritin, elevated lactate dehydrogenase, and segmental chromosomal aberrations, all of which were more frequent in adrenal versus nonadrenal tumors (P < .001). Adrenal tumors were more likely than nonadrenal tumors (adjusted odds ratio, 2.09; 95% CI, 1.67 to 2.63; P < .001) and thoracic tumors were less likely than nonthoracic tumors (adjusted odds ratio, 0.20; 95% CI, 0.11 to 0.39; P < .001) to have MYCN amplification after controlling for age, stage, and histologic grade. EFS and OS differed significantly according to the primary site (P < .001 for both comparisons). After controlling for age, MYCN status, and stage, patients with adrenal tumors had higher risk for events (hazard ratio, 1.13 compared with nonadrenal tumors; 95% CI, 1.03 to 1.23; P = .008), and patients with thoracic tumors had lower risk for events (HR, 0.79 compared with nonthoracic; 95% CI, 0.67 to 0.92; P = .003).

CONCLUSION

Clinical and biologic features show important differences by NB primary site, with adrenal and thoracic sites associated with inferior and superior survival, respectively. Future studies will need to investigate the biologic origin of these differences.

Secondary malignant neoplasms after high-dose chemotherapy and autologous stem cell rescue for high-risk neuroblastoma

BACKGROUND

Outcomes for high-risk neuroblastoma remain poor. Modern treatment protocols utilizing intense induction followed by myeloablative consolidation chemotherapy with autologous stem cell rescue (ASCR) have improved survival rates, but the long-term sequelae, including development of secondary malignant neoplasms (SMN), are just now surfacing.

METHODS

We retrospectively reviewed data from 87 patients with high-risk neuroblastoma who were treated with intensive induction chemotherapy followed by ASCR between January 1991 and July 2011 following one of two institutional protocols: Chicago Pilot 1 (CP1; n = 12) and Chicago Pilot 2 (CP2; n = 75).

RESULTS

The 15-year overall survival rate for all 87 patients was 33.9% (95% confidence interval [CI], 23.1-45.0%). The 10- and 15-year cumulative incidence of SMN was 16.5% (95%CI, 7.2-38.0%) and 34.2% (95%CI, 18.6-63.1%), respectively, without evidence of a plateau at 15 years. Six of the 10 patients (n = 2 in CP1 and n = 8 in CP2) who developed SMN had hematologic malignancies including acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS). Solid tumors included thyroid papillary carcinoma, chondrosarcoma, hepatocellular carcinoma, and biliary adenocarcinoma.

CONCLUSION

A significantly higher incidence of SMN, especially hematological malignancies, was observed in this cohort compared to older neuroblastoma studies, potentially due to exposure to epipodophyllotoxins and a high cumulative dose of alkylating agents these patients received. The risk of developing an SMN continued to increase with survival time and did not reach the plateau at 15 years. Although the number of the patients is relatively small, our study emphasizes the need for life-long follow-up of survivors who were treated using modern therapy.

Treatment of two cases with refractory, metastatic intermediate-risk neuroblastoma with isotretenoin alone or observation

Patients <12 months with favorable biology, metastatic neuroblastoma have >90% overall survival following treatment with chemotherapy and surgery. We report two infants with favorable biology, stage 4 neuroblastoma with refractory disease after standard intermediate-risk chemotherapy and additional retrieval chemotherapy. One patient was treated with six additional cycles of isotretinoin and the other observed. Both remain clinically well with persistent disease but no evidence of tumor progression for 28 and 13 months following completion of cytotoxic treatment. Similar to residual tumor in primary sites, refractory metastatic disease may not portend a poor outcome in patients with favorable biology, intermediate-risk neuroblastoma.

Time to disease progression in children with relapsed or refractory neuroblastoma treated with ABT-751: a report from the Children's Oncology Group (ANBL0621)

BACKGROUND

ABT-751, an orally bioavailable sulfonamide binds the colchicine site of beta-tubulin and inhibits microtubule polymerization. Prior phase I studies established the recommended dose in children with solid tumors as 200 mg/m(2) PO daily × 7 days every 21 days and subjects with neuroblastoma experienced prolonged stable disease. We conducted a phase 2 study (NCT00436852) in children and adolescents with progressive neuroblastoma to determine if ABT-751 prolonged the time to progression (TTP) compared to a hypothesized standard based on a historical control population.

PROCEDURE

Children and adolescents (n = 91) with a median (range) age 7.7 (2.3-21.5) years and progressive neuroblastoma were enrolled and stratified by disease status into disease measureable by CT/MRI (n = 47) or disease assessable by (123) I-metaiodobenzylguanine scintigraphy (MIBG, n = 44). Response was evaluated using RECIST for measureable disease and the Curie score for MIBG-avid disease.

RESULTS

ABT-751 was well tolerated. The objective response rate was 7%. The median TTP was 42 days (95% CI: 36, 56) in the measureable disease stratum and 45 days (95% CI: 42, 85) in the MIBG-avid disease stratum. TTP was similar to the historical control group (n = 136, median TTP 42 days). For the combined strata (n = 91), 1-year progression free survival (PFS) was 13 ± 4% and overall survival (OS) was 48 ± 5%.

CONCLUSIONS

The low objective response rate and failure to prolong TTP indicate that ABT-751 is not sufficiently active to warrant further development for neuroblastoma. However, this trial demonstrates the utility of TTP as the primary endpoint in phase 2 trials in children and adolescents with neuroblastoma.

TET1-mediated hydroxymethylation facilitates hypoxic gene induction in neuroblastoma

The ten-eleven-translocation 5-methylcytosine dioxygenase (TET) family of enzymes catalyzes the conversion of 5-methylcytosine (5-mC) to 5-hydroxyme-thylcytosine (5-hmC), a modified cytosine base that facilitates gene expression. Cells respond to hypoxia by inducing a transcriptional program regulated in part by oxygen-dependent dioxygenases that require Fe(II) and α-ketoglutarate. Given that the TET enzymes also require these cofactors, we hypothesized that the TETs regulate the hypoxia-induced transcriptional program. Here, we demonstrate that hypoxia increases global 5-hmC levels, with accumulation of 5-hmC density at canonical hypoxia response genes. A subset of 5-hmC gains colocalize with hypoxia response elements facilitating DNA demethylation and HIF binding. Hypoxia results in transcriptional activation of TET1, and full induction of hypoxia-responsive genes and global 5-hmC increases require TET1. Finally, we show that 5-hmC increases and TET1 upregulation in hypoxia are HIF-1 dependent. These findings establish TET1-mediated 5-hmC changes as an important epigenetic component of the hypoxic response.

Neuroblastoma in older children, adolescents and young adults: a report from the International Neuroblastoma Risk Group project

BACKGROUND

Neuroblastoma in older children and adolescents has a distinctive, indolent phenotype, but little is known about the clinical and biological characteristics that distinguish this rare subgroup. Our goal was to determine if an optimal age cut-off exists that defines indolent disease and if accepted prognostic factors and treatment approaches are applicable to older children.

PROCEDURE

Using data from the International Neuroblastoma Risk Group, among patients ≥18 months old (n = 4,027), monthly age cut-offs were tested to determine the effect of age on survival. The prognostic effect of baseline characteristics and autologous hematopoietic cell transplant (AHCT) for advanced disease was assessed within two age cohorts; ≥5 to <10 years (n = 730) and ≥10 years (n = 200).

RESULTS

Older age was prognostic of poor survival, with outcome gradually worsening with increasing age at diagnosis, without statistical evidence for an optimal age cut-off beyond 18 months. Among patients ≥5 years, factors significantly prognostic of lower event-free survival (EFS) and overall survival (OS) in multivariable analyses were INSS stage 4, MYCN amplification and unfavorable INPC histology classification. Among stage 4 patients, AHCT provided a significant EFS and OS benefit. Following relapse, patients in both older cohorts had prolonged OS compared to those ≥18 months to <5 years (P < 0.0001).

CONCLUSIONS

Despite indolent disease and infrequent MYCN amplification, older children with advanced disease have poor survival, without evidence for a specific age cut-off. Our data suggest that AHCT may provide a survival benefit in older children with advanced disease. Novel therapeutic approaches are required to more effectively treat these patients.

Metastatic neuroblastoma confined to distant lymph nodes (stage 4N) predicts outcome in patients with stage 4 disease: A study from the International Neuroblastoma Risk Group Database

PURPOSE

The presence of distant metastases is one of the most powerful predictors of outcome in patients with neuroblastoma. However, the pattern of metastatic spread is not incorporated into current risk stratification systems. Small case series have suggested that patients with neuroblastoma who have metastatic disease limited to distant lymph nodes (4N disease) may have improved outcomes.

PATIENTS AND METHODS

We analyzed retrospective data from the International Neuroblastoma Risk Group database for patients diagnosed from 1990 to 2002. 4N patients were compared with the remaining stage 4 patients (non-4N), excluding those with missing metastatic site data.

RESULTS

In all, 2,250 International Neuroblastoma Staging System stage 4 patients with complete data were identified, of whom 146 (6.5%) had 4N disease. For 4N patients, event-free survival (EFS; 5-year, 77% ± 4%) and overall survival (OS; 5-year, 85% ± 3%) were significantly better than EFS (5-year, 35% ± 1%) and OS (5-year, 42% ± 1%) for non-4N stage 4 patients (P < .001). 4N patients were more likely to be younger (P < .001) and have tumors with favorable characteristics, including absence of MYCN amplification (89% v 69%; P < .001). In a multivariable analysis, 4N disease remained a significant predictor of outcome (hazard ratio for non-4N v 4N: 3.40 for EFS and 3.69 for OS). Within subgroups defined by age at diagnosis and tumor MYCN status, 4N disease was significantly associated with improved outcomes.

CONCLUSION

4N represents a subgroup with better outcome than that of other patients with metastatic disease. These findings suggest that the biology and treatment response of 4N tumors differ from other stage 4 tumors, and less intensive therapy should be considered for this cohort. Future exploration of biologic factors determining the pattern of metastatic spread is warranted.

Validation of a prognostic multi-gene signature in high-risk neuroblastoma using the high throughput digital NanoString nCounter™ system

Microarray-based molecular signatures have not been widely integrated into neuroblastoma diagnostic classification systems due to the complexities of the assay and requirement for high-quality RNA. New digital technologies that accurately quantify gene expression using RNA isolated from formalin-fixed paraffin embedded (FFPE) tissues are now available. In this study, we describe the first use of a high-throughput digital system to assay the expression of genes in an "ultra-high risk" microarray classifier in FFPE high-risk neuroblastoma tumors. Customized probes corresponding to the 42 genes in a published multi-gene neuroblastoma signature were hybridized to RNA isolated from 107 FFPE high-risk neuroblastoma samples using the NanoString nCounter™ Analysis System. For classification of each patient, the Pearson's correlation coefficient was calculated between the standardized nCounter™ data and the molecular signature from the microarray data. We demonstrate that the nCounter™ 42-gene panel sub-stratified the high-risk cohort into two subsets with statistically significantly different overall survival (p = 0.0027) and event-free survival (p = 0.028). In contrast, none of the established prognostic risk markers (age, stage, tumor histology, MYCN status, and ploidy) were significantly associated with survival. We conclude that the nCounter™ System can reproducibly quantify expression levels of signature genes in FFPE tumor samples. Validation of this microarray signature in our high-risk patient cohort using a completely different technology emphasizes the prognostic relevance of this classifier. Prospective studies testing the prognostic value of molecular signatures in high-risk neuroblastoma patients using FFPE tumor samples and the nCounter™ System are warranted.

Age-dependent prognostic effect by Mitosis-Karyorrhexis Index in neuroblastoma: a report from the Children's Oncology Group

Prognostic effects of Mitosis-Karyorrhexis Index (MKI) used in the International Neuroblastoma Pathology Classification (INPC) are age-dependent. A total of 4,282 neuroblastomas reviewed at the Children's Oncology Group Neuroblastoma Pathology Reference Laboratory (8/1/2001-3/31/2012) included 2,365 low-MKI (L-MKI), 1,068 intermediate-MKI (I-MKI), and 849 high-MKI (H-MKI) tumors. Cox proportional hazards models were fit to determine age cut-offs at which the relative risk of event/death was maximized in each MKI class. Backward-selected Cox models were fit to determine the prognostic strength of the age cut-offs for survival in the presence of other prognostic factors. The age cut-offs used in the INPC for L-MKI tumors (<60 months, n  =  2,710, 84.0% ± 1.0% event-free survival [EFS], 93.8 ± 0.7% overall survival [OS] vs ≥60 months, n  =  195, 49.8% ± 4.6% EFS, 71.7% ± 4.1% OS; P < 0.0001) and I-MKI tumors (<18 months, n  =  568, 83.8% ± 2% EFS, 93.7% ± 1.3% OS vs ≥18 months, n  =  500, 51.4% ± 2.9% EFS, 66.7% ± 2.7% OS; P < 0.0001) were within the effective range for distinguishing prognostic groups. As for H-MKI tumors (no cut-off age in the INPC, 51.0% ± 2.2% EFS, 64.4% ± 2.1% OS), a new cut-off of 3-4 months was suggested (<4 months, n  =  38, 82.3% ± 8.4% EFS, 81.8% ± 8.5% OS vs ≥4 months, n  =  811, 49.6% ± 2.2% EFS, 63.7% ± 2.1% OS, P  =  0.0034 and 0.0437, respectively). Multivariate analyses revealed that cut-offs of 60 and 18 months for L-MKI and I-MKI tumors, respectively, were independently prognostic. However, the cut-off of 4 months for H-MKI tumors did not reach statistical significance in the presence of other factors. The age cut-offs for MKI classes (60 months for L-MKI, 18 months for I-MKI, no cut-off for H-MKI) in the current INPC are reasonable and effective for distinguishing prognostic groups with increased risk of event/death for older patients.

Neuroblastoma of undifferentiated subtype, prognostic significance of prominent nucleolar formation, and MYC/MYCN protein expression: a report from the Children's Oncology Group

BACKGROUND

This study sought to investigate biological/clinicopathological characteristics of neuroblastoma, undifferentiated subtype (NBUD).

METHODS

This study examined 157 NBUD cases filed at the Children's Oncology Group Neuroblastoma Pathology Reference Laboratory, and survival rates of the patients were analyzed with known prognostic factors. Immunostainings for MYCN and MYC protein were performed on 68 tumors.

RESULTS

NBUD cases had a poor prognosis (48.4% ± 5.0% 3-year event-free survival [EFS]; 56.5% ± 5.0% overall survival [OS]), and were often associated with high mitosis-karyorrhexis index (MKI, 65%), prominent nucleoli (PN, 83%), ≥ 18 months of age (75%), MYCN amplification (MYCN-A, 83%), diploid pattern (63%), and 1pLOH (loss of heterozygosity (72%). However, these prognostic indicators, except for MYCN status, had no significant impact on survival. Surprisingly, EFS for patients with MYCN-A tumors (53.4% ± 5.6%) was significantly better (P=.0248) than for patients with MYCN-nonamplified (MYCN-NA) tumors (31.7% ± 11.7%), with MYCN-NA and PN (+) tumors having the worst prognosis (9.3%  ± 8.8%, P=.0045). Immunohistochemically, MYCN expression was found in 42 of 48 MYCN-A tumors. In contrast, MYC expression was almost exclusively found in the MYCN-NA tumors (9 of 20) especially when they had PN (8 of 11). Those patients with only MYC-positive tumors had the worst EFS (N=8, 12.5% ± 11.7%) compared with only MYCN-positive (N=39, 49.9% ± 17.7%) and both negative tumors (N=15, 70.0% ± 17.1%) (P= .0029). High MKI was often found in only MYCN-positive (30 of 38) but rarely in only MYC-positive (2 of 8) tumors.

CONCLUSIONS

NBUD represents a unique subtype of neuroblastoma associated with a poor prognosis. In this subtype, MYC protein expression may be a new prognostic factor indicating more aggressive clinical behavior than MYCN amplification and subsequent MYCN protein expression.

Purged versus non-purged peripheral blood stem-cell transplantation for high-risk neuroblastoma (COG A3973): a randomised phase 3 trial

BACKGROUND

Myeloablative chemoradiotherapy and immunomagnetically purged autologous bone marrow transplantation has been shown to improve outcome for patients with high-risk neuroblastoma. Currently, peripheral blood stem cells (PBSC) are infused after myeloablative therapy, but the effect of purging is unknown. We did a randomised study of tumour-selective PBSC purging in stem-cell transplantation for patients with high-risk neuroblastoma.

METHODS

Between March 16, 2001, and Feb 24, 2006, children and young adults (<30 years) with high-risk neuroblastoma were randomly assigned at diagnosis by a web-based system (in a 1:1 ratio) to receive either non-purged or immunomagnetically purged PBSC. Randomisation was done in blocks stratified by International Neuroblastoma Staging System stage, age, MYCN status, and International Neuroblastoma Pathology classification. Patients and treating physicians were not masked to treatment assignment. All patients were treated with six cycles of induction chemotherapy, myeloablative consolidation, and radiation therapy to the primary tumour site plus meta-iodobenzylguanidine avid metastases present before myeloablative therapy, followed by oral isotretinoin. PBSC collection was done after two induction cycles. For purging, PBSC were mixed with carbonyl iron and phagocytic cells removed with samarium cobalt magnets. Remaining cells were mixed with immunomagnetic beads prepared with five monoclonal antibodies targeting neuroblastoma cell surface antigens and attached cells were removed using samarium cobalt magnets. Patients underwent autologous stem-cell transplantation with PBSC as randomly assigned after six cycles of induction therapy. The primary endpoint was event-free survival and was analysed by intention-to-treat. The trial is registered with ClinicalTrials.gov, number NCT00004188.

FINDINGS

495 patients were enrolled, of whom 486 were randomly assigned to treatment: 243 patients to receive non-purged PBSC and 243 to received purged PBSC. PBSC were collected from 229 patients from the purged group and 236 patients from the non-purged group, and 180 patients from the purged group and 192 from the non-purged group received transplant. 5-year event-free survival was 40% (95% CI 33-46) in the purged group versus 36% (30-42) in the non-purged group (p=0·77); 5-year overall survival was 50% (95% CI 43-56) in the purged group compared with 51% (44-57) in the non-purged group (p=0·81). Toxic deaths occurred in 15 patients during induction (eight in the purged group and seven in the non-purged group) and 12 during consolidation (eight in the purged group and four in the non-purged group). The most common adverse event reported was grade 3 or worse stomatitis during both induction (87 of 242 patients in the purged group and 93 of 243 patients in the non-purged group) and consolidation (131 of 177 in the purged group vs 145 of 191 in the non-purged group). Serious adverse events during induction were grade 3 or higher decreased cardiac function (four of 242 in the purged group and five of 243 in the non-purged group) and elevated creatinine (five of 242 in the purged group and six of 243 non-purged group) and during consolidation were sinusoidal obstructive syndrome (12 of 177 in the purged group and 17 of 191 in the non-purged group), acute vascular leak (11 of 177 in the purged group and nine of 191 in the non-purged group), and decreased cardiac function (one of 177 in the purged group and four of 191 in the non-purged group).

INTERPRETATION

Immunomagnetic purging of PBSC for autologous stem-cell transplantation did not improve outcome, perhaps because of incomplete purging or residual tumour in patients. Non-purged PBSC are acceptable for support of myeloablative therapy of high-risk neuroblastoma.

Children's Oncology Group's 2013 blueprint for research: neuroblastoma

Estimated 5-year survival rates for patients with non-high-risk and high-risk neuroblastoma are 90% and 50%, respectively. Recent clinical trials have shown excellent outcomes with reduced therapy for non-high-risk disease. For patients with high-risk neuroblastoma treated with chemoradiotherapy, surgery, and stem cell transplantation, the addition of anti-disialoganglioside (GD2) immunotherapy plus cytokines improves survival. Upcoming trials will study the incorporation of targeted radionuclide therapy prior to myeloablative chemotherapy into high-risk treatment. Phase 2 trials will investigate druggable target(s) including mTOR inhibition and GD2-directed therapy in combination with chemotherapy for patients with recurrent neuroblastoma, and ALK inhibition for those with ALK-aberrant tumors.

Development of an open-source, flexible framework for complex inter-institutional disparate data sharing and collaboration

Clinical information, "-omic" datasets, and tissue samples are difficult to harmonize and manage for data mining. We have developed a platform for storing clinical research data while providing access to associated data from other information stores. Data on 34 metrics from 11,000 neuroblastoma patients were instantiated into a database. The Django web framework was used to create a model for rapid development of tools and views with a front-end interface for generating complex queries. Working with Nationwide Children's Hospital, we can now consume their tissue inventory data through an API. The end-user sees the number of patients who both match their search and have tissue available. Since initial implementation, the current tasks revolve around developing a governance structure and the necessary data use agreements. Efforts now are to (1) update the data with 5000 more patients, and (2) link to genomic data stores, facilitating disparate data acquisition for research studies.

Progression-free survival of two cases of high-risk neuroblastoma with refractory/relapsed disease following surgery alone

Outcome for the vast majority of high-risk neuroblastoma patients with refractory or relapsed disease is dismal. We report two high-risk patients who remain progression-free for more than 113 and 18 months following the diagnosis of refractory/relapsed disease who were treated with surgery alone. Complete resolution of a refractory thoracic mass and relapsed liver nodules was observed in one patient. The refractory/relapsed disease in the second patient has remained stable. In both cases, the tumor showed histologic evidence of neuroblastoma maturation. These cases demonstrate that refractory/relapsed neuroblastoma is clinically heterogeneous and highlight the need for better biomarkers to optimize patient care.

Peripheral neuroblastic tumors with genotype-phenotype discordance: a report from the Children's Oncology Group and the International Neuroblastoma Pathology Committee

BACKGROUND

Of 4,706 peripheral neuroblastic tumors (pNTs) registered on the Children's Cancer Group and Children's Oncology Group Neuroblastoma Study between 1989 and 2010, 51 cases (1.1%) had genotype-phenotype discordance characterized by MYCN amplification (indicating poor prognosis) and Favorable Histology (indicating better prognosis).

PROCEDURE

To distinguish prognostic subgroups in the genotype-phenotype discordant pNTs, two subgroups, "conventional" and "bull's eye," were identified based on the nuclear morphology. The "conventional" tumors (35 cases) included: Neuroblastoma, poorly differentiated subtype (NB-PD, 26 cases) with "salt-and-pepper" nuclei; neuroblastoma, differentiating subtype (4 cases); ganglioneuroblastoma, intermixed (3 cases); and ganglioneuroma, maturing subtype (2 cases). The "bull's eye" tumors included NB-PD with prominent nucleoli (16 cases). Clinicopathologic characteristics of these two subgroups were analyzed. N-myc protein expression was tested immunohistochemically on available tumors.

RESULTS

No significant difference was found between these two subgroups in the distribution of prognostic factors such as age at diagnosis, clinical stage, histopathology category/subtype, mitosis-karyorrhexis index, ploidy, 1p LOH, and unbalanced 11q LOH. However, prognosis of the patients with "conventional" tumors (5-year EFS 85.7 ± 12.2%; OS 89.3 ± 10.3%) was significantly better than those with "bull's eye" tumors (EFS 31.3 ± 13.0%; OS 42.9 ± 16.2%; P = 0.0010 and 0.0008, respectively). Immunohistochemically all (11/11) tested "conventional" tumors were negative, and 10/11 tested "bull's eye" tumors were positive for N-myc protein expression.

CONCLUSIONS

Based on the presence or absence of prominent nucleoli (the putative site of RNA synthesis/accumulation leading to N-myc protein expression), two prognostic subgroups, "conventional" with a better prognosis and "bull's eye" with a poor prognosis, were distinguished among the genotype-phenotype discordant pNTs.

Semiquantitative mIBG scoring as a prognostic indicator in patients with stage 4 neuroblastoma: a report from the Children's oncology group

Radiolabeled metaiodobenzylguanidine (mIBG) is a highly sensitive and specific marker for detecting neuroblastoma. A semiquantitative mIBG score (Curie score [CS]) was assessed for utility as a prognostic indicator for a cohort of patients with high-risk metastatic disease.

METHODS

mIBG scans from 280 patients with mIBG-avid, stage 4 neuroblastoma enrolled on the Children's Oncology Group (COG) protocol A3973 were evaluated at diagnosis (n = 280), after induction chemotherapy (n = 237), and after an autologous stem cell transplantation (n = 178). Individual mIBG scans were evaluated at 10 different anatomic regions, with the scoring of each site (0-3) based on the extent of disease at that anatomic region.

RESULTS

There was no correlation between CS at diagnosis and subsequent treatment outcome. Patients with a CS > 2 after induction therapy had a significantly worse event-free survival (EFS) than those with scores ≤ 2 (3-y EFS: 15.4% ± 5.3% vs. 44.9% ± 3.9%, respectively; P < 0.001). A postinduction CS > 2 identified a cohort of patients at greater risk for an event, independent of other known neuroblastoma factors, including age, MYCN status, ploidy, mitosis-karyorrhexis index, and histologic grade. For MYCN-amplified tumors, the presence (CS > 0) versus absence (CS = 0) of residual mIBG avidity after induction was associated with a significantly worse outcome (3-y EFS: 11.8% ± 7.8% vs. 49.6% ± 7.7%, respectively; P = 0.003). After transplantation, patients with a CS > 0 had an EFS inferior to that of patients with a CS of 0 (3-y EFS: 28.9% ± 6.8% vs. 49.3% ± 4.9%, respectively [n = 133]; P = 0.009).

CONCLUSION

Curie scoring carries prognostic significance in the management of patients with high-risk neuroblastoma. In particular, patients with CSs > 2 after induction have extremely poor outcomes and should be considered for alternative therapeutic strategies.

Two cases of localized neuroblastoma with multiple segmental chromosomal alterations and metastatic progression

Surgery alone is curative for most children with localized MYCN-non-amplified neuroblastoma. However, 10-15% will develop recurrent loco-regional disease, and very rarely, patients will relapse metastatically. Currently, it is not possible to predict which child with localized, MYCN-non-amplified neuroblastoma will develop disseminated disease. We report two children who presented with favorable biology, localized neuroblastoma and subsequently relapsed with metastatic disease after treatment with surgery. Whole-genome DNA copy number analyses performed on the diagnostic tumors identified 15 (case 1) and 8 (case 2) segmental chromosomal alterations. Further analysis of the prognostic value of whole-genome analysis in children with localized neuroblastoma is warranted.