A Pilot Study on the Utility of Serum Metabolomics in Neuroblastoma Patients and Xenograft Models

BACKGROUND

Improved prediction of neuroblastoma (NB) behavior is needed to detect treatment-refractory disease and may allow further reduction in therapy for some patients. In this regard, serum metabolomic analysis has proven utility in several cancer types. We hypothesize that serum metabolomic analysis will correlate with risk-group classification for patients with NB, and sensitively detect NB in murine xenograft models.

PROCEDURE

A pilot study was done on Children's Oncology Group (COG) tumor bank sera from 10 patients (five high-, five low-risk). An institutional pilot study was carried out on five patients comparing sera obtained during active versus minimal disease (complete response/very good partial response; CR/VGPR).

XENOGRAFT

Flank tumors were established in Nu/Nu mice by injection of NB cell lines (IMR-32, SH-EP, SK-N-AS). Serum for comparison was drawn pre-injection, at 1 week after injection when there was no visible tumor, and again once tumors were grossly visible. Comparisons were also made between tumor bearing mouse serum and supernatants from NB cell lines.

METABOLOMIC ANALYSIS

Samples were analyzed by nuclear magnetic resonance and/or gas chromatography-mass spectrometry. Multivariate data analysis was conducted using SIMCA-P (Umetrics).

RESULTS

Serum metabolomic analysis differentiated high- and low-risk patients as well as active disease from CR/VGPR. Differences were in nitrogen, amino acid, and carbohydrate metabolism, as well as ketosis. The serum metabolomic signature in murine xenograft models sensitively detected NB cells and correlated with disease burden. Similar metabolic changes attributable to NB were noted in both human and murine serum.

CONCLUSIONS

Serum metabolomic analysis can distinguish several characteristics of NB. A larger analysis of COG banked sera is warranted.

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.

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.

Allogeneic hematopoietic cell transplantation for neuroblastoma: the CIBMTR experience

While the role of auto-HCT is well established in neuroblastoma, the role of allo-HCT is controversial. The CIBMTR conducted a retrospective review of 143 allo-HCT for NBL reported in 1990-2007. Patients were categorized into two different groups: those who had not (Group 1) and had (Group 2) undergone a prior auto HCT (n=46 and 97, respectively). One-year and five-year overall survival (OS) were 59% and 29% for Group 1 and 50% and 7% for Group 2. Amongst donor types, disease free survival (DFS) and OS were significantly lower for unrelated transplants at 1 and 3 years but not 5 years post-HCT. Patients in complete response (CR) or very good partial response (VGPR) at transplant had lower relapse rates and better DFS and OS, compared to those not in CR or VGPR. Our analysis indicates that allo-HCT can cure some neuroblastoma patients, with lower relapse rates and improved survival in patients without a history of prior auto-HCT as compared to those patients who had previously undergone auto-HCT. Although the data do not address why either strategy was chosen for patients, allo-HCT after a prior auto-HCT appears to offer minimal benefit. Disease recurrence remains the most common cause of treatment failure.

Treatment of chest wall osteosarcoma presenting as second primary after treatment of neuroblastoma

Only 2 cases of osteosarcoma as a second primary malignancy after neuroblastoma have been reported in the literature. We present a case of chest wall osteosarcoma that developed in a 14-year-old boy 7 years after completion of chemotherapy, autologous peripheral blood stem cell transplantation, radiation, and resection for stage 3, high-risk neuroblastoma. A biopsy of a painful chest wall mass arising from the right third rib diagnosed osteosarcoma. He went on to have preoperative chemotherapy followed by wide local excision and chest wall reconstruction. He then received additional chemotherapy. This case highlights the importance of close observation for second malignancies in this patient population.

Tandem stem cell rescue as consolidation therapy for high-risk neuroblastoma

BACKGROUND

Despite aggressive treatment for high-risk neuroblastoma (NB), event-free survival (EFS) remains <40%. In single arm studies, intensifying therapy with high-dose chemotherapy and tandem autologous stem cell rescue (HDC/SCR) improved outcome. We retrospectively describe our institutional experience in using HDC/SCR for patients with high-risk NB, focusing on outcome and acute toxicities.

METHODS

Eighty-four patients with high-risk NB at Children's Healthcare of Atlanta treated over a 12-year time period underwent HDC/SCR as part of upfront therapy; 28 patients received a single HDC/SCR and 56 patients received tandem HDC/SCR. The two groups were compared in terms of EFS, overall survival (OS), and acute transplant related toxicities.

RESULTS

Patients who received tandem HDC/SCR had a significantly improved EFS compared with patients who received a single HDC/SCR (4-year EFS 59.3 ± 6.7% vs. 26.8 ± 9.2%, P=0.01). Similarly, the 4-year OS was improved in patients receiving tandem HDC/SCR, though this did not reach statistical significance (70.6 ± 9.2% vs. 44.7±11.2%, P=0.06). Multivariate regression confirmed the prognostic role of the treatment group. None of the patients who underwent a single HDC/SCR developed veno-occlusive disease (VOD), while 17% of patients who underwent tandem HDC/SCR developed mild-to-severe VOD. Rates of other transplant-related acute toxicities were similar.

CONCLUSION

Tandem HDC/SCR for patients with high-risk NB seems to improve survival without significant increases in acute toxicities. This needs to be validated in randomized prospective trials.

Comparison of ¹²³I-metaiodobenzylguanidine (MIBG) and ¹³¹I-MIBG semi-quantitative scores in predicting survival in patients with stage 4 neuroblastoma: a report from the Children's Oncology Group

BACKGROUND

¹²³I-metaiodobenzylguanidine (MIBG) scans are preferable to ¹³¹I-MIBG for neuroblastoma imaging as they deliver less patient radiation yet have greater sensitivity in disease detection. Both ¹²³I-MIBG and ¹³¹I-MIBG scans were used for disease assessments of neuroblastoma patients enrolled on Children's Oncology Group (COG) high-risk study A3973. The hypothesis was that ¹²³I-MIBG and ¹³¹I-MIBG scans were sufficiently similar for clinical purposes in terms of ability to predict survival.

PROCEDURE

Patients enrolled on COG A3973 with stage 4 disease who completed ¹²³I-MIBG or ¹³¹I-MIBG scans at diagnosis, post-induction, post-transplant, or post-biotherapy were analyzed. The performance of the Curie score for each MIBG scan type in predicting survival was evaluated. At each time point, survival curves for ¹²³I-MIBG versus ¹³¹I-MIBG were compared using the log-rank test.

RESULTS

Of the 413 patients on A3973 with at least one MIBG scan, 350 were stage 4. The 5-year event-free survival (EFS) and overall survival (OS) rates were 33.4 ± 3.6% and 45.6 ± 4.0% (N = 350). At post-induction, EFS (P = 0.3501) and OS (P = 0.5337) for ¹²³I-MIBG versus ¹³¹I-MIBG were not significantly different. Similarly, comparisons at the three other time points were non-significant.

CONCLUSIONS

We found no evidence of a statistically significant difference in outcome by type of scan. For future survival analyses of MIBG Curie scores, ¹²³I-MIBG and ¹³¹I-MIBG results may be combined and analyzed overall, without adjustment for scan type.

The use of central laboratories and remote electronic data capture to risk-adjust therapy for pediatric acute lymphoblastic leukemia and neuroblastoma

The Children's Oncology Group (COG) is a National Cancer Institute (NIH)-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 cancers, 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.

New therapeutic targets for the treatment of high-risk neuroblastoma

High-risk neuroblastoma remains a major problem in pediatric oncology, accounting for 15% of childhood cancer deaths. Although incremental improvements in outcome have been achieved with the intensification of conventional chemotherapy agents and the addition of 13-cis-retinoic acid, only one-third of children with high-risk disease are expected to be long-term survivors when treated with current regimens. In addition, the cost of cure can be quite high, as surviving children remain at risk for additional health problems related to long-term toxicities of treatment. Further advances in therapy will require the targeting of tumor cells in a more selective and efficient way so that survival can be improved without substantially increasing toxicity. In this review we summarize ongoing clinical trials and highlight new developments in our understanding of the molecular biology of neuroblastoma, emphasizing potential targets or pathways that may be exploitable therapeutically.

Management and outcome of stage 3 neuroblastoma

PURPOSE

The management of patients with International Neuroblastoma Staging System (INSS) stage 3 neuroblastoma (NB) is not consistent worldwide. We describe a single centre approach at Memorial Sloan-Kettering Cancer Centre (MSKCC) from 1991 to 2007 that minimises therapy except for those patients with MYCN-amplified NB.

METHODS

In this retrospective analysis of 69 patients, tumour MYCN was not amplified in 53 and amplified in 16. Event-free survival (EFS) and overall survival (OS) were determined by Kaplan-Meier analysis.

RESULTS

Fourteen patients with non-MYCN-amplified tumours were treated with surgery alone (group A) and the remaining 39 (group B) with surgery following chemotherapy that was initiated and administered at non-MSKCC institutions. Chemotherapy was discontinued after surgery in 38/39 of the latter. The 10-year EFS and OS for all patients with MYCN-non-amplified NB were 74.9+/-16.9% and 92.6+/-5.5%, respectively. There was no difference in OS between groups A and B (p=0.2; 10-year OS for groups A and B was 84.6+/-14% and 97.1+/-2.9%, respectively). Patients with MYCN-amplified disease (group C) underwent dose-intensive induction, tumour resection and local radiotherapy: 13 achieved complete or very good partial remission, and 10 received myeloablative chemotherapy. 11/16 patients also received 3F8-based immunotherapy: 10 remain free of disease. The 10-year EFS and OS for patients with MYCN-amplified neuroblastoma treated with immunotherapy were both 90.9+/-8.7%.

CONCLUSION

Patients with MYCN-non-amplified stage 3 NB can be successfully treated with surgery without the need for radiotherapy or continuation of chemotherapy. Combination of dose-intensive chemotherapy, surgery, radiotherapy and immunotherapy was associated with a favourable outcome for most patients with MYCN-amplified stage 3 NB.

28 years of high-dose therapy and SCT for neuroblastoma in Europe: lessons from more than 4000 procedures

Between 1978 and 2006, the European Group for Blood and Marrow Transplantation registered 4098 high-dose therapy (HDT) procedures followed by stem cell rescue (SCR) (3974 autologous/124 allogeneic) in patients with neuroblastoma. The 5-year rates for overall (OS) and event-free survival are 37 and 32%, respectively. The median age at diagnosis is 3.9 years (0.3-62 years) with 76 patients older than 18 years. Patients above 10 years carry a 2.5-fold higher risk. Younger patients cure significantly (<0.001) better with OS rates of 40 and 30% for age groups 2-4 years and 4-10 years, respectively. Their risks are about twofold higher than that of patients below 2 years with OS rates of 60%. The better the quality of remission status before HDT/SCT the better are the observed OS rates: 43% in CR1 (1199 patients) and 42% for CR2 (140 patients), and 36% for those in very good partial or partial remission (1413 patients) and 21% for those with sensitive relapse (134 patients). Patients reported with stable disease in first remission still had an OS rate of 30%. Multivariate analysis shows significantly better OS in the age group of less than 2 years (<0.0001), as well as a better quality of remission status before HDT/SCT (P<0.0001), with the use of peripheral stem cells (P=0.014), autologous SCT (P=0.031) and busulphan/melphalan HDT (P<0.001). Busulphan/melphalan HDT/SCT in first remission achieves an OS of 48%, while it is only 35% with other regimens (P<0.001), including melphalan alone, other melphalan-containing regimens, a variety of other drugs given as a single HDT as well as the addition of TBI or sequential HDT/SCT procedures. Further progress in the field may only be expected from large-scale international randomized trials.

Stem cell transplantation for neuroblastoma

High-risk neuroblastoma is a childhood malignancy with a poor prognosis. Gradual improvements in survival have correlated with therapeutic intensity, and the ability to harvest, process and store autologous hematopoietic stem cells has allowed for dose intensification beyond marrow tolerance. The use of high-dose chemotherapy with autologous hematopoietic stem cell rescue in consolidation has resulted in improvements in survival, although further advances are still needed. Newer approaches to SCT and supportive care, most notably the transition to PBSC, have resulted in further improvement in survival and decreases in treatment-related mortality. Research into experimental approaches to hematopoietic SCT is ongoing.