Katherine K. Matthay

Treatment of High-Risk Neuroblastoma with Intensive Chemotherapy, Radiotherapy, Autologous Bone Marrow Transplantation, and 13-cis-Retinoic Acid

BACKGROUND Children with high-risk neuroblastoma have a poor outcome. In this study, we assessed whether myeloablative therapy in conjunction with transplantation of autologous bone marrow improved event-free survival as compared with chemotherapy alone, and whether subsequent treatment with 13-cis-retinoic acid (isotretinoin) further improves event-free survival. METHODS All patients were treated with the same initial regimen of chemotherapy, and those without disease progression were then randomly assigned to receive continued treatment with myeloablative chemotherapy, total-body irradiation, and transplantation of autologous bone marrow purged of neuroblastoma cells or to receive three cycles of intensive chemotherapy alone. All patients who completed cytotoxic therapy without disease progression were then randomly assigned to receive no further therapy or treatment with 13-cis-retinoic acid for six months. RESULTS The mean (+/-SE) event-free survival rate three years after the first randomization was significantly better among the 189 patients who were assigned to undergo transplantation than among the 190 patients assigned to receive continuation chemotherapy (34+/-4 percent vs. 22+/-4 percent, P=0.034). The event-free survival rate three years after the second randomization was significantly better among the 130 patients who were assigned to receive 13-cis-retinoic acid than among the 128 patients assigned to receive no further therapy (46+/-6 percent vs. 29+/-5 percent, P=0.027). CONCLUSIONS Treatment with myeloablative therapy and autologous bone marrow transplantation improved event-free survival among children with high-risk neuroblastoma. In addition, treatment with 13-cis-retinoic acid was beneficial for patients without progressive disease when it was administered after chemotherapy or transplantation.

Anti-GD2 Antibody with GM-CSF, Interleukin-2, and Isotretinoin for Neuroblastoma

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. (Funded by the National Institutes of Health and the Food and Drug Administration; ClinicalTrials.gov number, NCT00026312.)

The International Neuroblastoma Risk Group (INRG) Classification System: An INRG Task Force Report

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 (Childrens 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 < or = 85%, > or = 50% to < or = 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.

The International Neuroblastoma Pathology Classification (the Shimada system).

The International Neuroblastoma Pathology Committee, which is comprised of six member pathologists, was convened with the objective of proposing a prognostically significant and biologically relevant classification based on morphologic features of neuroblastic tumors (NTs) (i.e., neuroblastoma, ganglioneuroblastoma, and ganglioneuroma).

Molecular Biology of Neuroblastoma

UNLABELLED PURPOSE AND RESULTS: Neuroblastoma, the most common solid extracranial neoplasm in children, is remarkable for its clinical heterogeneity. Complex patterns of genetic abnormalities interact to determine the clinical phenotype. The molecular biology of neuroblastoma is characterized by somatically acquired genetic events that lead to gene overexpression (oncogenes), gene inactivation (tumor suppressor genes), or alterations in gene expression. Amplification of the MYCN proto-oncogene occurs in 20% to 25% of neuroblastomas and is a reliable marker of aggressive clinical behavior. No other oncogene has been shown to be consistently mutated or overexpressed in neuroblastoma, although unbalanced translocations resulting in gain of genetic material from chromosome bands 17q23-qter have been identified in more than 50% of primary tumors. Some children have an inherited predisposition to develop neuroblastoma, but a familial neuroblastoma susceptibility gene has not yet been localized. Consistent areas of chromosomal loss, including chromosome band 1p36 in 30% to 35% of primary tumors, 11q23 in 44%, and 14q23-qter in 22%, may identify the location of neuroblastoma suppressor genes. Alterations in the expression of the neurotrophins and their receptors correlate with clinical behavior and may reflect the degree of neuroblastic differentiation before malignant transformation. Alterations in the expression of genes that regulate apoptosis also correlate with neuroblastoma behavior and may help to explain the phenomenon of spontaneous regression observed in a well-defined subset of patients. CONCLUSION The molecular biology of neuroblastoma has led to a combined clinical and biologic risk stratification. Future advances may lead to more specific treatment strategies for children with neuroblastoma.

Long-Term Results for Children With High-Risk Neuroblastoma Treated on a Randomized Trial of Myeloablative Therapy Followed by 13-cis-Retinoic Acid: A Children's Oncology Group Study

UNLABELLED 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% +/- 8% [corrected]; 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 than nonmyeloablative chemo therapy; neither myeloablative therapy with [corrected] autologous hematopoietic cell rescue nor cis-RA given after consolidation therapy significantly improved OS.

The International Neuroblastoma Risk Group (INRG) Staging System: An INRG Task Force Report

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.

Retinoid therapy of high-risk neuroblastoma

Retinoids are derivatives of vitamin A that include all trans-retinoic acid (ATRA), 13-cis-retinoic acid, (13-cis-RA), and fenretinide (4-HPR). High levels of either ATRA or 13-cis-RA can cause arrest of cell growth and morphological differentiation of human neuroblastoma cell lines, and phase I trials showed that higher and more sustained drug levels were obtained with 13-cis-RA relative to ATRA. A phase III randomized trial showed that high-dose, pulse therapy with 13-cis-RA given after completion of intensive chemoradiotherapy (with or without autologous bone marrow transplantation) significantly improved event-free survival in high-risk neuroblastoma. The cytotoxic retinoid 4-HPR achieved multi-log cell kills in neuroblastoma cell lines resistant to ATRA and 13-cis-RA, and a pediatric phase I trial has shown it to be well tolerated. Cytotoxicity of 4-HPR is mediated at least in part by increasing tumor cell ceramide levels and combining 4-HPR with ceramide modulators increased anti-tumor activity in pre-clinical models. Thus, further clinical trials of 4-HPR in neuroblastoma, and of 4-HPR in combination with ceramide modulators, are warranted.

Allelic deletion at 11q23 is common in MYCN single copy neuroblastomas

Deletions of the long arm of chromosome 11 (11q) have been noted in primary neuroblastomas, but a comprehensive analysis has not been performed. Therefore, we analysed 331 neuroblastomas (295 sporadic, 15 familial and 21 tumor-derived cell lines) to determine the prevalence of 11q allelic deletions, to map the location of a putative tumor suppressor gene and to perform clinical correlative studies. Assays for loss of heterozygosity (LOH) were performed at 24 microsatellite loci spanning 11q. LOH was observed at multiple 11q loci in 129/295 (44%) sporadic neuroblastomas, 5/15 (33%) familial neuroblastomas, and 5/21 (24%) neuroblastoma cell lines. A single region of 2.1 cM within 11q23.3, flanked by markers D11S1340 and D11S1299, was deleted in all specimens with 11q LOH. Allelic loss at 11q23 was inversely related to MYCN amplification (P<0.001). Within the subset of cases with a single copy of MYCN, 11q LOH was associated with advanced stage disease (P=0.008), unfavorable histopathology (P=0.042), and decreased overall survival probability (P=0.008). However, 11q LOH was not independently prognostic in multivariate analyses. These data support the hypothesis that a tumor suppressor gene mapping within 11q23.3 is commonly inactivated during the malignant evolution of a large subset of neuroblastomas, especially those with unamplified MYCN.

Biologic Factors Determine Prognosis in Infants With Stage IV Neuroblastoma: A Prospective Children’s Cancer Group Study

PURPOSE A prospective Childrens Cancer Group study, CCG-3881, has been completed to determine if a more accurate prediction of prognosis by biologic features can identify subgroups of infants with stage IV neuroblastoma (NBL) who require differing intensities of treatment. PATIENTS AND METHODS One hundred thirty-four infants were registered from June 1989 to August 1995, with a median follow-up of 47.1 months (range, 0 to 88 months). The biologic factors examined were tumor MYCN copy number, Shimada histopathologic classification, serum ferritin, and bone marrow immunocytology (sensitivity, one tumor cell per 10(5) bone marrow cells). Patients treated on CCG-3881 (n = 116) received four-drug chemotherapy for 9 months (cisplatin, cyclophosphamide, doxorubicin, and etoposide), with surgery and local radiation to residual disease. After January 1991, all subsequent infants with tumor MYCN amplification (n = 18) were transferred after one cycle of therapy to the high-risk CCG-3891 protocol (open January 1991 to April 1996) for more intensive treatment. RESULTS The 3-year event-free survival (EFS) and overall survival (mean +/- SD) for the 134 infants were 63% +/- 5% and 71% +/- 5%, respectively. Patients whose tumors were without MYCN amplification had a 93% +/- 4% 3-year EFS, whereas those with amplified MYCN had a 10% +/- 7% 3-year EFS (P <. 0001). Each of the other biologic features studied had prognostic significance in univariate analysis but not after stratifying by MYCN copy number. CONCLUSION Infants less than 1 year of age at diagnosis with stage IV NBL have a much improved outcome compared with children >/= 1 year of age. Nonamplified MYCN tumors identify a group of infants with a 93% +/- 4% EFS, whereas amplified MYCN copy number clearly identifies patients who are unlikely to survive despite intensive chemotherapy.