Improved survival for patients with advanced neuroblastoma after high-dose combined chemotherapy based in part on N-myc amplification

Therapeutic potential of targeting MYCN: A case series report of neuroblastoma with MYCN amplification

INTRODUCTION

Neuroblastoma (NB) with MYCN amplification has a poor prognosis and high mortality. The potential molecular biological relationship between clinical features and MYCN amplification should be explored.

METHODS

NB patients were examined by fluorescence in situ hybridization (FISH) for MYCN amplification in the tumor mass or bone marrow samples to determine whether MYCN was amplified. A series of eleven MYCN-amplified NB patients were included. The age, primary site, tumor size, specific biomarkers, and invaded organs were analyzed. All patients accepted standardized treatment of surgery, chemotherapy, and radiotherapy. Progression-free survival (PFS) and overall survival (OS) were evaluated.

RESULTS

The median age at diagnosis was 24 months. Nine patients (81.8%) were in stage IV, with high serum neuron-specific enolase (NSE) expression, normal urine vanillylmandelic acid (VMA) level and extensive metastases. All patients accepted a chemotherapy protocol with 8 to 10 cycles, and 9 patients (81.8%) were sensitive to the initial chemotherapy protocol. At the end of follow-up, four patients (36.3%) died with a median OS of 15 months. Five patients (45%) survived with a median PFS of 13 months. Two patients were still receiving chemotherapy.

CONCLUSION

Given the effect of MYCN amplification on poor outcome in NB, novel treatments targeting MYCN should be developed for patients with NB.

Secondary osteosarcoma arising from osteochondroma following autologous stem cell transplantation with total-body irradiation for neuroblastoma: A case report

The present study reports the first case of malignant transformation to osteosarcoma arising from osteochondroma following childhood total-body irradiation (TBI). The association between TBI and later development of osteochondroma is well-known; however, malignant degeneration arising from radiation-induced osteochondroma is rare. The current study describes the case of a 17-year-old boy with osteosarcoma arising from osteochondroma of the left distal humerus, which developed following TBI. TBI was administered as part of a conditioning regimen received prior to autologous peripheral hematopoietic stem cell transplantation (HSCT) at the age of 6 years, following an initial diagnosis of neuroblastoma at the age of 5 years. The patient subsequently underwent preoperative chemotherapy followed by wide local excision and reconstruction with an extracorporeally irradiated autograft. Postoperative chemotherapy was administered, and the patient demonstrated no clinical or radiographic evidence of recurrence after 40 months of follow-up. To the best of our knowledge, this is only the second reported case of malignant degeneration of osteochondroma following childhood TBI, and the first reported case of transformation to osteosarcoma. The current case highlights the importance of close observation for secondary malignancies in this patient population.

Antimetabolite-based therapy in childhood T-cell acute lymphoblastic leukemia: a report of POG study 9296

PURPOSE

A previous Pediatric Oncology Group (POG) study showed high incidence of secondary acute myelogenous leukemia (AML) in children treated for T-cell acute lymphoblastic leukemia (T-ALL) or higher-stage lymphoblastic lymphoma. To prevent secondary neoplasms, induce prolonged asparagine depletion, and maintain high event-free survival (EFS) in children with newly diagnosed T-ALL or higher-stage non-Hodgkins lymphoma (NHL), we designed this pilot study to determine feasibility and safety of substituting methotrexate/mercaptopurine for teniposide/cytarabine and PEG-asparaginase for native asparaginase.

PATIENTS AND METHODS

Forty-five patients were entered, 29 with T-ALL and 16 with higher-stage NHL. Forty-two of 45 patients achieved complete remission (CR), and 27 completed the therapy in continuous CR. Treatment consisted of 4-week induction then 6 weeks consolidation and ten 9-week maintenance cycles. Therapy primarily comprised antimetabolites, anthracyclines, alkylating agents, and asparaginase. Expected chemotherapy duration was 100 weeks.

RESULTS

Forty-two of 45 patients achieved CR, and 27 completed therapy. The most common toxicities were Grade 3 or 4 myelosuppression after cyclophosphamide/cytarabine and allergic reactions to asparaginase. Two died of sepsis early in maintenance. Five-year EFS was 68.5% (SE 9.1%) for T-ALL and 81.3% (SE 9.8%) for NHL. Five-year EFS was 73.1% (SE 6.8%) for the entire cohort. No patients treated entirely on this study developed secondary neoplasms. One patient taken off study for asparaginase toxicity was treated with multiagent therapy that contained teniposide, and died from secondary myelodysplasia (sMDS)/AML.

CONCLUSION

Substituting methotrexate/mercaptopurine for teniposide/cytarabine and PEG-asparaginase for native asparaginase in a dose-intensive regimen was feasible in children and young adults with newly diagnosed T-ALL or higher-stage NHL. EFS was not compromised and secondary neoplasms were decreased.

MYCN gene overrepresentation detected in primary neuroblastoma tumour cells without amplification

Neuroblastoma is the most frequent solid extracranial neoplasm of childhood, with a median age of presentation of under 2 years. This tumour is highly malignant in patients older than 12 months of age with metastatic disease. Clinical studies have confirmed that amplification of the MYCN proto-oncogene is one of the best prognostic indicators of poor outcome. Approximately 30% of neuroblastoma tumours present MYCN amplification at diagnosis. Far less is known about the incidence and consequences of overrepresentation of the gene due to duplication or rearrangement of the chromosome arm in which the gene is situated. This study has analysed 110 neuroblastomas by FISH and has detected a gain of 1-3 copies per cell of MYCN in 8% of MYCN-non-amplified tumours. In these primary tumours, cells gained small numbers of additional MYCN genes by two mechanisms: formation of an isochromosome 2p, or an unbalanced translocation involving the short arm of chromosome 2 (with MYCN) and various partner chromosomes. Quantitative RT-PCR showed three- to seven-fold elevated MYCN expression in three tumours. Although the follow-up time to date is still short, clinical outcome suggests that low-level overexpression of the MYCN gene does not enhance tumour aggressiveness and rapidity of disease progression, as is often seen in neuroblastoma with MYCN amplification. It is hypothesized that the small elevation in MYCN expression could alter the regulation of apoptosis, as has been shown in experimental models.

Stephen L. Gans overseas lecture. Mass screening for neuroblastoma in Japan: lessons learned and future directions

BACKGROUND/PURPOSE

Since 1985, a nationwide mass screening program (MS) for neuroblastoma has been conducted for 6-month-old infants throughout Japan, resulting in the detection of more than 1,900 cases of neuroblastoma. The outcome of these patients has been excellent: more than 97% of them are alive. Yet, several reports suggest that the number of advanced-stage neuroblastoma patients over 1 year of age has not changed substantially. The current report focuses on the 15-year experience with MS of the Kyushu Pediatric Oncology Study Group.

METHODS

The clinical and biological features of neuroblastoms detected (n = 320) and not detected by MS (n = 245) were compared. Regional and national statistics for neuroblastoma before and after 1985 were analyzed using standard epidemiologic measures for the occurrence of disease.

RESULTS

The majority of the MS-positive cases were biologically favorable and had an excellent outcome. In contrast, the majority of non-MS patients in whom neuroblastoma later developed had advanced-stage, unfavorable-prognosis tumors. The overall mortality rate of neuroblastoma in the Kyushu area was not improved by MS.

CONCLUSIONS

The optimal time for screening is the point at which neuroblastomas regressing spontaneously can no longer be detected, but more aggressive disease can be found. A birth cohort study could determine the optimal timing for a second screening. Identification of other new prognostic factors may be required.

Clinical and biologic characteristics for recurring neuroblastoma at mass screening cases in Japan

BACKGROUND

It is said that most cases detected by neuroblastoma mass screening at 6 months of age tend to have a favorable clinical course after a surgical resection either with or without mild chemotherapy. However, a few cases have an unfavorable outcome. In the current study, the authors analyzed the clinical and biologic characteristics for recurring neuroblastoma in mass screening cases.

METHODS

In 245 cases detected through mass screening in the Kyushu area in Japan, the clinical data and biologic features (N-myc status, DNA ploidy, Shimada histology, neuron-specific enolase (NSE), ferritin) were investigated, whereas, in particular, the data for recurring cases also were analyzed.

RESULTS

Of 245 cases, 28 tumors had one or more biologically unfavorable prognostic factors, and 6 patients experienced recurrence. Three of the six patients with recurring disease underwent a complete resection of the primary tumor, whereas three cases had undergone an incomplete resection of the tumor. Regarding the initial chemotherapy, three cases received mild chemotherapy, two cases received no chemotherapy, and one case had high-dose multidrug chemotherapy. Regarding biologic prognostic factors, four of six cases with recurring disease had one or more unfavorable factors, whereas two cases had no unfavorable factors. Regarding the outcome after recurrence, four cases are CR, one case has a stable residual tumor, and one case died of disease with N-myc amplification.

CONCLUSIONS

Most neuroblastomas detected by mass screening at 6 months of age have biologically favorable factors. However, approximately 10% of the cases had one or more unfavorable factors and thus might have a higher risk of recurrence than the patients with no unfavorable factors. Conversely, some cases with recurring disease had no unfavorable factors; however, the reason for this is still unclear. A long-term follow-up for mass screening cases is important, and it also might be necessary to research the established biologic factors and identify other new prognostic factors.