A pilot study of tandem high-dose chemotherapy with stem cell rescue as consolidation for high-risk neuroblastoma: Children's Oncology Group study ANBL00P1

Increasing treatment intensity has improved outcomes for children with neuroblastoma. We performed a pilot study in the Children’s Oncology Group (COG) to assess feasibility and toxicity of a tandem myeloablative regimen without total body irradiation (TBI) supported by autologous CD34 selected peripheral blood stem cells. Forty-one patients with high-risk neuroblastoma were enrolled; eight patients did not receive any myeloablative consolidation procedure, and seven received only one. Two patients out of 41 (4.9%) experienced transplant-related mortality. CD34 selection was discontinued after subjects were enrolled due to serious viral illness. From the time of study enrollment, the overall 3-year event-free survival (EFS) and overall survival (OS) were 44.8±9.6% and 59.2±9.2% (N=41). These results demonstrate that tandem transplantation in the cooperative group setting is feasible and support a randomized comparison of single versus tandem myeloablative consolidation with PBSC support for high-risk neuroblastoma.

Segmental chromosomal alterations have prognostic impact in neuroblastoma: a report from the INRG project

Background:

In the INRG dataset, the hypothesis that any segmental chromosomal alteration might be of prognostic impact in neuroblastoma without MYCN amplification (MNA) was tested.

Methods:

The presence of any segmental chromosomal alteration (chromosome 1p deletion, 11q deletion and/or chromosome 17q gain) defined a segmental genomic profile. Only tumours with a confirmed unaltered status for all three chromosome arms were considered as having no segmental chromosomal alterations.

Results:

Among the 8800 patients in the INRG database, a genomic type could be attributed for 505 patients without MNA: 397 cases had a segmental genomic type, whereas 108 cases had an absence of any segmental alteration. A segmental genomic type was more frequent in patients >18 months and in stage 4 disease (P<0.0001). In univariate analysis, 11q deletion, 17q gain and a segmental genomic type were associated with a poorer event-free survival (EFS) (P<0.0001, P=0.0002 and P<0.0001, respectively). In multivariate analysis modelling EFS, the parameters age, stage and a segmental genomic type were retained in the model, whereas the individual genetic markers were not (P<0.0001 and RR=2.56; P=0.0002 and RR=1.8; P=0.01 and RR=1.7, respectively).

Conclusion:

A segmental genomic profile, rather than the single genetic markers, adds prognostic information to the clinical markers age and stage in neuroblastoma patients without MNA, underlining the importance of pangenomic studies.

Criteria for evaluation of disease extent by (123)I-metaiodobenzylguanidine scans in neuroblastoma: a report for the International Neuroblastoma Risk Group (INRG) Task Force

BACKGROUND

Neuroblastoma is an embryonic tumour of the sympathetic nervous system, metastatic in half of the patients at diagnosis, with a high preponderance of osteomedullary disease, making accurate evaluation of metastatic sites and response to therapy challenging. Metaiodobenzylguanidine (mIBG), taken into cells via the norepinephrine transporter, provides a sensitive and specific method of assessing tumour in both soft tissue and bone sites. The goal of this report was to develop consensus guidelines for the use of mIBG scans in staging, response assessment and surveillance in neuroblastoma.

METHODS

The International Neuroblastoma Risk Group (INRG) Task Force, including a multidisciplinary group in paediatric oncology of North and South America, Europe, Oceania and Asia, formed a subcommittee on metastatic disease evaluation, including expert nuclear medicine physicians and oncologists, who developed these guidelines based on their experience and the medical literature, with approval by the larger INRG Task Force.

RESULTS

Guidelines for patient preparation, radiotracer administration, techniques of scanning including timing, energy, specific views, and use of single photon emission computed tomography are included. Optimal timing of scans in relation to therapy and for surveillance is reviewed. Validated semi-quantitative scoring methods in current use are reviewed, with recommendations for use in prognosis and response evaluation.

CONCLUSIONS

Metaiodobenzylguanidine scans are the most sensitive and specific method of staging and response evaluation in neuroblastoma, particularly when used with a semi-quantitative scoring method. Use of the optimal techniques for mIBG in staging and response, including a semi-quantitative score, is essential for evaluation of the efficacy of new therapy.

Prophylaxis of venous thromboembolism in the US: improving hospital performance

Venous thromboembolism (VTE) prevention has been recognized as the most important practice for improving patient safety in hospitals. To be effective, VTE prophylaxis must be appropriately prescribed with respect to type, dose and duration. Large-scale studies of medical discharge records have highlighted low rates of appropriate thromboprophylaxis in hospitalized medical patients, especially those with cancer or severe lung disease. Lack of prophylaxis and an insufficient duration are the most common forms of inappropriate prophylaxis. Multifaceted, active, quality improvement initiatives have been developed and shown to successfully increase the appropriate prescribing of VTE prophylaxis in patients at risk. By increasing the use of appropriate VTE prophylaxis in at-risk patients, the disease burden of hospital-acquired VTE and its resulting complications can be reduced.

Irinotecan plus temozolomide in children with recurrent or refractory neuroblastoma: A phase II Children's Oncology Group study

10011

Background: Treatment of children with relapsed or refractory neuroblastoma (NB) remains a challenge. Responses to irinotecan (IRN) + temozolomide (TEM) were seen in NB xenograft-bearing mice, and objective responses were observed in patients with NB treated on a phase I study of this combination. Methods: A phase II study of IRN (10 mg/m2/dose IV daily × 5 days times; 2 weeks) + TEM (100 mg/m2/dose PO daily × 5 days) for children with relapsed or refractory NB was conducted. A one-stage design (endpoint: best overall response) required 5 or more responders out of the first 25 evaluable patients on each of two strata: 1) patients with disease measurable by CT or MRI; and 2) patients with disease detected only by bone marrow aspirate/biopsy and/or MIBG scan. Patients with stable disease or better after 3 cycles could receive an additional 3 cycles of study therapy. International Neuroblastoma Response Criteria were used for response assessment. Radiographic responses were centrally reviewed. Results: Fifty-five eligible and evaluable patients were enrolled, 28 on stratum 1 and 27 on stratum 2. Four responses were observed in the first 25 evaluable stratum 1 patients, and five responses were observed in the first 25 evaluable stratum 2 patients. Three patients had complete responses, but the overall objective response rate (CR+PR) was 16% (9/55). Eleven (stratum 1) and 13 (stratum 2) patients had stable disease. Less than 5% of patients experienced Grade 3 or 4 diarrhea. Although 18% of patients on stratum 1 and 35% of patients on stratum 2 experienced Grade 3 or 4 neutropenia during the first 3 cycles of therapy, <10% of all patients developed evidence of infection while neutropenic. Thrombocytopenia (Grade 3 or 4) was observed in only 7% of patients on stratum 1 and 12% on stratum 2. Conclusions: The combination of IRN+TEM was well tolerated in patients with recurrent or refractory NB. There were 9 objective responses, including 3 complete responses. The minimum desired response rate was attained within stratum 2, but not stratum 1. IRN+TEM may be an appropriate backbone for further study in the relapse setting in combination with novel, targeted agents.

No significant financial relationships to disclose.

Significance of tumor biology compared to metastatic pattern (INSS 4 versus 4s) and age for prognosis of neuroblastoma less than 18 months of age

10010

Background: Neuroblastoma is a heterogeneous disease with variability in outcome among different risk groups. Historically, INSS stage 4s neuroblastoma (age less than 12 months, stage 1 or 2 primary tumor with metastases limited to liver, skin and bone marrow) has a more favorable outcome than infant stage 4 disease. The aim was to determine if metastatic pattern (4 vs 4s) predicted favorable prognosis in infants < 12 months or in toddlers aged 12–18 months when stratifying by biology. Methods: Outcome was analyzed by log rank tests and Cox models for 656 infants with stage 4s neuroblastoma and 1,019 stage 4 patients < 18 months of age in the International Neuroblastoma Risk Group database (n=8,800). Prognostic factors (tumor ploidy, histology, grade, MKI, LDH, MYCN, 11q, 1p, primary site) were tested for association with age/stage subgroups (Fisher's exact test) and in Cox models. Results: MYCNamplification, 1p aberration, diploidy, and high MKI and LDH were more frequent in infant stage 4 than infant 4s tumors. The incidence of unfavorable biology was higher in toddlers aged 12–18 months, but did not differ with stage 4 vs. 4s pattern. EFS was significantly better for infants <12 months with stage 4s than stage 4 (p=0.0004). EFS was similar for toddlers 12–18 months for stage 4 vs. 4s pattern (p=0.3893). Within the 717 patients with 4s pattern of metastases, age 12–18 months had worse EFS than <12 months (p<0.0001). After adjustment for age in 6 separate models, MYCN, 11q, 1p, MKI, and LDH were statistically significant prognostic factors. Although treatment regimens differed, EFS was similar for <12 months vs. 12–18 months for MYCN not amplified patients in both 4S pattern (p=0.8469) and stage 4 (p=0.3783). Conclusions: For patients with MYCN not amplified tumors, outcome for patients 12–18 months is similar to those <12 months regardless of the pattern of metastases. Tumor biology is more critical than metastatic pattern for prognosis of patients aged 12–18 months with stage 4 neuroblastoma. [Table: see text]

No significant financial relationships to disclose.

Consensus criteria for sensitive detection of minimal neuroblastoma cells in bone marrow, blood and stem cell preparations by immunocytology and QRT-PCR: recommendations by the International Neuroblastoma Risk Group Task Force

Disseminating disease is a predictive and prognostic indicator of poor outcome in children with neuroblastoma. Its accurate and sensitive assessment can facilitate optimal treatment decisions. The International Neuroblastoma Risk Group (INRG) Task Force has defined standardised methods for the determination of minimal disease (MD) by immunocytology (IC) and quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) using disialoganglioside G(D2) and tyrosine hydroxylase mRNA respectively. The INRG standard operating procedures (SOPs) define methods for collecting, processing and evaluating bone marrow (BM), peripheral blood (PB) and peripheral blood stem cell harvest by IC and QRT-PCR. Sampling PB and BM is recommended at diagnosis, before and after myeloablative therapy and at the end of treatment. Peripheral blood stem cell products should be analysed at the time of harvest. Performing MD detection according to INRG SOPs will enable laboratories throughout the world to compare their results and thus facilitate quality-controlled multi-centre prospective trials to assess the clinical significance of MD and minimal residual disease in heterogeneous patient groups.

Update on the development of the international neuroblastoma risk group (INRG) classification schema

9503

Background: Modern treatment strategies for neuroblastoma (NB) are tailored according to patient risk. However, it is not currently possible to compare the results of clinical studies conducted around the globe because the criteria used to define risk are not uniform. A committee of international investigators with expertise in NB have worked during the past 2 years to develop a uniform International NB Risk Group (INRG) Classification System for pre-treatment stratification. Methods: Investigators from North America and Australia (COG); Europe (SIOPEN and Germany), and Japan collated data on 8,800 children with NB diagnosed between 1990 and 2002. Survival tree regression analyses tested 13 potential prognostic factors. Tumor differentiation, MKI, and diagnostic category were evaluated individually in lieu of the International NB Pathology Classification (INPC) system to determine if these histologic features had prognostic value independent from age. To stage patients at the time of diagnosis prior to surgery, a new staging system was developed (INRGSS) based on the presence or absence of image-defined risk factors (IDRFs) and metastases. Results: Since statistical analyses demonstrated support for an optimal age cut- off between 14–19 months, 18 months was selected. In addition to age, stage, MYCN amplification, tumor differentiation, ploidy, and genetic aberrations of 11q were found to be the most highly prognostically significant factors. These clinical and biological factors were combined to define 15 INRG pre-treatment groups. Patients with low- (3 groups), intermediate- (4 groups), high- (4 groups), or ultra-high-risk NB (4 groups) had EFS of ≥85%, >70–85%, >50–70%, or <50%, respectively. Conclusion: International collaborative studies in NB will be greatly facilitated by the INRG classification system which will allow comparisons of different risk-based therapeutic approaches in homogeneous patient cohorts.

No significant financial relationships to disclose.

Age, tumor grade, and mitosis-karyorrhexis index (MKI) are independently predictive of outcome in neuroblastoma (NB)

9558

Background: NB is a rare pediatric malignancy (USA incidence 1:100,000), and treatment is tailored according to risk. NB patients (pts) in the Children's Oncology Group are stratified to low, intermediate or high risk according to age at diagnosis, stage of disease, MYCN status, histopathology, and tumor cell ploidy. The International NB Pathologic Classification (INPC) uses age at diagnosis to classify tumors as Favorable or Unfavorable histology. This results in duplication of the prognostic contribution of age when both age and INPC, with other factors, are used to assign risk groups or build multivariable models of prognostic factors. To eliminate the confounding contribution of age and INPC, and determine if tumor pathology is predictive of outcome independent of age, we performed multivariable modeling using the underlying pathologic components of INPC. Methods: Using the largest cohort of NB pts ever assembled (n=11,054; 1980–2002; international), 1,860 pts with known age, INPC, diagnosis, tumor grade of differentiation, MKI, and outcome were identified. Half were selected at random (reserving the other half for validation) for analysis. A Cox multivariable model was used to perform survival tree regression to identify factors statistically significantly (p<0.05) prognostic of event-free (relapse, progression, secondary malignancy, death) survival (EFS). Factors tested were age, diagnosis, grade, and MKI. Results: Age (<547 v. ≥547 days) was the most significant factor (p<0.0001). Within pts <547 days, no factors were significantly prognostic. Within pts ≥547 days, stroma-poor NB and nodular (composite) ganglioNB was associated with significantly lower EFS than intermixed ganglioNB and ganglioneuroma, maturing (p<0.0001). Pts were further stratified within the latter diagnoses by MKI (Low/Intermediate v. High) (p=0.0016). These results were validated in the other half of the cohort. Conclusions: Histologic features of NB tumors are predictive of outcome. To remove confounding of the prognostic contribution of age, the underlying histologic features of the tumor (diagnosis, MKI, grade) should be used instead of INPC class to assign pts to risk groups or identify prognostic factors with multivariable models.

No significant financial relationships to disclose.

Expression of the multidrug transporter genes ABCC1/MRP1, ABCC3/MRP3, and ABCC4/MRP4 are powerful predictors of clinical outcome in childhood neuroblastoma

9524

Background: We have previously shown, both retrospectively and prospectively, that high-level expression of the multidrug transporter gene ABCC1/MRP1, is strongly predictive of poor outcome in the childhood cancer neuroblastoma (NEJM, 334:231–8, 1996; JCO, 24:1546–53, 2006), and that ABCC1/MRP1 can be regulated by the MYCN oncogene. The contribution of other ABCC family genes to clinical outcome in this disease has now been examined. Methods: Real-time quantitative PCR was used to determine ABCC gene expression in a large prospectively accrued cohort (n=209) of primary untreated neuroblastomas from patients enrolled on POG biology protocol 9047. Results: Older age, advanced stage, and MYCN amplification were all predictive of poor outcome in the cohort. Amongst the ABCC family, high levels of ABCC1 and ABCC4, but low levels of ABCC3, were strongly associated with reduced survival and event-free survival (P<0.005) in the overall study population, and also in subgroups of patients lacking MYCN amplification. Following adjustment for the effect of MYCN gene amplification and other prognostic indicators by multivariate analysis, expression of ABCC1 (HR=2.3; p=0.03), ABCC3 (HR=2.7; p=0.0141), ABCC4 (HR=3.4; p=0.002) retained significant prognostic value for outcome, whereas age and MYCN amplification lost all prognostic significance. By combining the expression of these three transporter genes, patients could be stratified into groups having excellent, intermediate or poor outcome (EFS=84%, 59%, 17%, respectively). Conclusions: These data, suggest that ABCC1, 3 and 4 are amongst the most powerful prognostic markers yet identified for childhood neuroblastoma and as such represent important targets for potential therapeutic intervention.

No significant financial relationships to disclose.

Response and toxicity to a dose-intensive multi-agent chemotherapy induction regimen for high risk neuroblastoma (HR-NB): A Children's Oncology Group (COG A3973) study

9505

Background: Myeloablative consolidation improves outcome for HR-NB pts, especially for pts in CR prior to consolidation. We assessed the toxicity and CR+VGPR rate of a dose-intensive multi-agent chemotherapy induction based upon the N7 regimen (JCO 22:4888, 2004) prior to myeloablative consolidation and peripheral blood autologous stem cell transplant (ASCT). Methods: Between 2/2001 and 3/2006, 489 eligible newly diagnosed HR- NB pts received the following induction consisting of 6 cycles of chemotherapy q 21 days. Cycles 1, 2, 4 & 6: cyclophosphamide 4.2 g/m2, doxorubicin 75 mg/m2, and vincristine 2 mg/m2 and Cycles 3 &5: cisplatin 200 mg/m2 and etoposide 600 mg/m2. Surgical resection of primary occurred after cycle 5. Following induction pts received purged or unpurged ASCT (as randomized), radiation, and then 13-cis-retinoic acid (13-cis-RA). Response was assessed after cycles 2 & 6 using the International Neuroblastoma Response Criteria and analyzed as intent-to-treat. Results: Median age was 3.1 yrs, 44% of 392 tumors tested had MYCN amplification. Fourteen pts (3%) died during induction (5 infection, 4 bleed into tumor, 4 compromised organ function from tumor, 1 unrelated to tumor/therapy). Patients experienced the following grade 3 & 4 toxicities at least once during induction: neutropenia 70%, thrombocytopenia 71%, hearing loss 6%, cardiac function 2% and renal function 3%. Documented infection occurred in 24% of cycles (90% bacterial, 3% viral, 7% fungal). Responses among the 489 pts at end of induction were CR 24%, VGPR 28%, PR 26%, SD 7%, and PD15%, with morphologically detectable bone marrow (BM) disease cleared in 87% and no disease remaining by MIBG scan in 55% of pts MIBG positive at baseline. Conclusions: Despite increased dose intensity of this regimen, toxicity was not excessive compared to prior HR-NB regimens. In a multi-center setting, the A3973 induction chemotherapy achieved morphologic BM clearance in 87% of pts prior to consolidation. The CR/VGPR rate of 52% is similar to that of prior less intensive regimens. The impact of this induction response on survival within the context of ASCT and 13-cis-RA on COG A3973 will be determined with longer follow-up.

No significant financial relationships to disclose.

The pharmacokinetics (PK) and pharmacodynamics (PD) of ABT-751 in children with recurrent neuroblastoma or other solid tumors

9557

Background: ABT-751 is an orally administered agent that binds to the colchicine site on β-tubulin and blocks microtubule formation. We studied the PK and PD of ABT-751 and its sulfate and glucuronide conjugates in children enrolled on a phase 1 trial in solid tumors and a pilot study in neuroblastoma. Methods: Seventy-two children (2–18 yrs) received ABT-751 on a once, daily × 7d or daily × 21d schedule. Sixty had PK plasma sampling (53 sets analyzed), and 41 had a 24h urine collection after the first dose. Drug concentrations were quantified with a LC/MS/MS assay. Results: Median (range) plasma PK parameters are shown in the table . ABT-751 was rapidly absorbed (Tmax , 2h), and the Cmax and AUC0-8 increased in proportion to dose. The median molar ratio of the sulfate plasma AUC0-8 to glucuronide plasma AUC0-8 was 1.5. The median (range) percent of the administered dose excreted in urine as ABT-751, glucuronide, or sulfate conjugates was 0.09 (0–0.4)%, 10.2 (1.0–38.5)%, and 12.6 (2.3–50.9)%, respectively. The median ABT-751 AUC0-8 was higher in patients with dose-limiting toxicity (DLT) compared to those without DLT on the 7d (118 vs. 74.5 μg·h/mL; P=0.014) and 21d (73.8 vs 49.3 μg·h/mL; P=0.049) schedules. In 28 patients with neuroblastoma, the AUC0-8 did not correlate with time to progression. Apparent clearance (CL/F) did not correlate with age or gender. Conclusions: PK samples were obtained from 83% (60/72) of children enrolled. The ABT-751 AUC0-8 was dose proportional; inter- and intra-patient variability was low. Patients who experienced DLT had higher ABT-751 AUC0-8. The mean CL/F of ABT-751 was similar to that observed in adults (40 mL/min/m2) but did not correlate with age or gender. The sulfate conjugate was the primary metabolite in plasma and urine. Urinary excretion was not a major route of elimination of the parent drug.

[Table: see text]

No significant financial relationships to disclose.

Prominent vascular endothelial proliferation in clinically aggressive neuroblastoma

10611

Background: Tumor blood vessels are disorganized and vascular endothelial cell proliferation (VEP) has been identified as a poor prognosticator in many adult cancers. To determine the clinical significance of VEP in neuroblastoma (NB), we evaluated blood vessel architecture in tumor sections from 51 children diagnosed at Children's Memorial Hospital, Chicago (CMH) and in 154 NB tumors on a Tissue Microarray (TMA) constructed at Children's Hospital of Philadelphia (CHOP). Methods: H&E-stained tumor sections were examined for the presence of structurally abnormal vessels and further characterized by immunostaining with anti-CD31 and von Willebrand factor (vWF) antibody to highlight endothelial cells. Tumors that contained vessels with disorganized walls and more than one endothelial cell layer were classified as VEP positive. Tumor sections that contained only thin walled vessels with no more than one layer of endothelial cells were classified as VEP negative. Associations between VEP and established clinico-pathologic features and outcome were assessed. Results: In the CHOP series, VEP was associated with high-risk group classification and MYCN amplification (p<0.001 and p=0.006). In the CMH series only 5 of the 10 children with MYCN amplification had VEP but 4 of these 5 patients have died, while there were no deaths in the subset of patients with MYCN amplified tumors that lacked VEP (n=5). In both study groups, VEP was significantly associated with Schwannian stroma-poor histology (CMH series: p=0.008; CHOP series: p<0.001) and decreased survival probability (CMH series: p=0.017; CHOP series: p= 0.014). Conclusions: The association between structurally abnormal vessels and poor outcome provides further support for the concept that angiogenesis plays an important role in determining the biologic behavior of NB tumors. Our results also indicate that angiogenesis is regulated differently in Schwannian stroma-rich versus stroma-poor NB tumors. Further studies investigating the activity of angiogenic inhibitors in children with clinically aggressive stroma-poor NB are warranted.

No significant financial relationships to disclose.

SPARC enhances tumor stroma formation and prevents fibroblast activation

Tumor growth is influenced by interactions between malignant cells and the tumor stroma. Although the normal host microenvironment is nonpermissive for neoplastic progression, tumor-reactive stroma, characterized by the presence of activated fibroblasts, promotes neoplastic growth and metastasis. Secreted protein, acidic and rich in cysteine (SPARC) is a matricellular glycoprotein that is capable of inhibiting the growth of several different types of cancer. Recently, we reported that SPARC also impairs the growth of xenografts comprised of 293 cells. In this study, we show that in addition to enhancing stroma formation, SPARC prevents fibroblast activation in 293 xenografts, suggesting that the anti-cancer effects of SPARC may be due, at least in part, to the formation of tumor stroma that is not supportive of tumor growth. In vitro, 3T3 fibroblasts cocultured with SPARC-transfected 293 cells remain negative for alpha-smooth muscle actin, whereas wild-type 293 cells induce fibroblast activation. Moreover, activation of 3T3 cells and primary fibroblasts by transforming growth factor beta is blocked by SPARC treatment. We also demonstrate that SPARC significantly increases basic fibroblast growth factor-induced fibroblast migration in vitro, indicating that it may recruit host fibroblasts to the tumor stroma. Taken together, our results suggest that in addition to blocking angiogenesis, SPARC may inhibit tumor growth by promoting the assembly of stroma that is non-permissive for tumor progression.

A topotecan-containing induction regimen for treatment of high risk neuroblastoma

9013

Background: We assessed the toxicity and feasibility of adding dose-intensive topotecan and cyclophosphamide to a multi-agent chemotherapy induction regimen for treatment of newly diagnosed high-risk neuroblastoma. Methods: Patients received 2 cycles of topotecan (starting dose 1.2 mg/m2/day for 5 days) and cyclophosphamide (400 mg/m2/day for 5 days) (T/C) followed by an additional 4 cycles of chemotherapy; cisplatin, etoposide alternating with vincristine, doxorubicin, cyclophosphamide. Pharmacokinetically guided topotecan dosing (target systemic exposure of AUC 50 - 70 ng/ml*hr determined by single day topotecan lactone levels) was performed. Chemotherapy cycles were scheduled every 21 days, PBSC harvest occurred after T/C cycles and surgical resection of residual primary tumor after cycle 5. Results: Thirty-one patients, 3 with INSS Stage 3 and 28 with Stage 4, were enrolled between April 2004 and November 2005. Median age at diagnosis was 2.5 years (range 0.9 - 9.35 years). Ten of 25 patients had tumor cell MYCN amplification and 21 of 22 tumors were classified as unfavorable Shimada histology by central review. Targeted topotecan systemic exposure was achieved in 87% (27/31) of patients during T/C cycle 1 and in 85% (23/27) of patients during T/C cycle 2. PBSC collections occurred as intended in 95% of patients (21/22 patients), median harvest 30.8 × 106 CD34+cells cell/kg (range 2.24 - 542). No dose limiting toxicities occurred. All patients experienced Grade 3 or 4 hematopoietic toxicity. Febrile neutropenia occurred in 79% (19/24) of patients during T/C cycles and 78% (18/23) of patients during subsequent cycles of induction therapy. Documented infection occurred in 12.5% (3/24) patients during T/C cycles and 26% (6/23) during subsequent induction cycles. Dose intensity of all chemotherapy agents was maintained in 95.8% (23/24) of patients. Conclusions: This pilot induction regimen was well tolerated with expected and reversible toxicities. Dose intensity of standard induction chemotherapy agents was not limited by the addition of dose-intensive topotecan. These data support investigation of efficacy in a Phase III clinical trial for newly diagnosed high-risk neuroblastoma.

[Table: see text]

The role of the multidrug resistance-associated protein 1 gene in neuroblastoma biology and clinical outcome

Multidrug resistance is a major obstacle to cancer treatment and leads to poor prognosis for the patient. Multidrug resistance-associated protein 1 (MRP1) can confer drug resistance in vitro and MRP1 may play a role in the development of drug resistance in several cancers including acute myeloid leukaemia, small cell lung cancer, T-cell leukaemia and neuroblastoma. The majority of patients with neuroblastoma present with widely disseminated disease at diagnosis and despite intensive treatment, the prognosis for such patients is dismal. There is increasing evidence for the involvement of the MYCN oncogene, and its down-stream target, MRP1, in the development of multidrug resistance in neuroblastoma. Given the importance of MRP1 overexpression in neuroblastoma, MRP1 inhibition may be a clinically relevant approach to improving patient outcome in this disease.

Evidence for an age cutoff greater than 365 days for neuroblastoma risk group stratification in the Children's Oncology Group

PURPOSE

In the Children's Oncology Group, risk group assignment for neuroblastoma is critical for therapeutic decisions, and patients are stratified by International Neuroblastoma Staging System stage, MYCN status, ploidy, Shimada histopathology, and diagnosis age. Age less than 365 days has been associated with favorable outcome, but recent studies suggest that older age cutoff may improve prognostic precision.

METHODS

To identify the optimal age cutoff, we retrospectively analyzed data from the Pediatric Oncology Group biology study 9047 and Children's Cancer Group studies 321p1-p4, 3881, 3891, and B973 on 3,666 patients (1986 to 2001) with documented ages and follow-up data. Twenty-seven separate analyses, one for each different age cutoff (adjusting for MYCN and stage), tested age influence on outcome. The cutoff that maximized outcome difference between younger and older patients was selected.

RESULTS

Thirty-seven percent of patients were younger than 365 days, and 64% were > or = 365 days old (4-year event-free survival [EFS] rate +/- SE: 83% +/- 1% [n = 1,339] and 45% +/- 1% [n = 2,327], respectively; P < .0001). Graphical analyses revealed the continuous nature of the prognostic contribution of age to outcome. The optimal 460-day cutoff we selected maximized the outcome difference between younger and older patients. Forty-three percent were younger than 460 days, and 57% were > or = 460 days old (4-year EFS rate +/- SE: 82% +/- 1% [n = 1,589] and 42% +/- 1% [n = 2,077], respectively; P < .0001). Using a 460-day cutoff (assuming stage 4, MYCN-amplified patients remain high-risk), 5% of patients (365 to 460 days: 4-year EFS 92% +/- 3%; n = 135) fell into a lower risk group.

CONCLUSION

The prognostic contribution of age to outcome is continuous in nature. Within clinically relevant risk stratification, statistical support exists for an age cutoff of 460 days.

p16/p14(ARF) cell cycle regulatory pathways in primary neuroblastoma: p16 expression is associated with advanced stage disease

p16 regulates the G(1)-S cell cycle transition by inhibiting the cyclin D-cyclin-dependent kinase (CDK)4/CDK6-mediated phosphorylation of retinoblastoma protein (pRb). We examined the possible derangement of the p16-CDK/cyclin D-pRb pathway in 40 primary neuroblastomas including 18 samples in the unfavorable stages (C and D) and 22 in the favorable stages (A, B, and Ds) by PCR, reverse transcription-PCR, Western blot, and immunohistochemistry and correlated the results with clinical outcome. No samples harbored alterations of the p16 gene. Interestingly, the samples in the unfavorable stages exhibited expression of p16 mRNA and protein more frequently than those in the favorable stages [mRNA, 9 of 18 (50%) versus 2 of 22 (9%), P = 0.006; protein, 5 of 16 (31%) versus 0 of 18 (0%), P = 0.013]. Alterations of the downstream components of the pathway were infrequent. pRb was deregulated in the majority of samples investigated [27 of 33 (82%), 24 with hyperphosphorylated pRb and 3 with no pRb protein]. The phosphorylation status of pRb did not correlate with p16 protein expression, suggesting that the elevated p16 protein may not be functioning properly to regulate the pathway. Among patients of all stages, p16 expression was significantly associated with a lower overall survival. There was no overexpression of MDM2, and loss of p14(ARF) expression and p53 mutation were infrequent events. Taken together, these findings suggest that up-regulated p16 expression may represent a unique feature of aggressive neuroblastoma.

Antiangiogenic therapy inhibits human neuroblastoma growth

BACKGROUND

Angiogenesis plays a crucial role in the progression and metastasis of malignant solid tumors. In many types of cancer, including neuroblastoma, high tumor vascularity correlates with poor outcome. Recently, a number of angiogenic inhibitors have been identified that had antitumor activity in preclinical studies.

PROCEDURE

To investigate the effect of the antiangiogenic agent TNP-470 on neuroblastoma tumor growth, we treated nude mice with TNP-470 after they were inoculated subcutaneously with 5 x 10(6) cells from the MYCN-amplified, human neuroblastoma cell line NBL-W-N.

RESULTS

TNP-470 did not significantly affect tumor growth when it was administered to mice with large tumors (>600 mm3). However, when TNP-470 was administered in the setting of microscopic disease 12 hr following tumor cell inoculation, treated mice had a significantly improved tumor-free survival at 12 weeks (P < 0.001), and overall survival at 45 weeks (P < 0.001), compared to control animals.

CONCLUSIONS

Our studies suggest that TNP-470 treatment may be most effective if it is administered in the setting of microscopic disease. We speculate that TNP-470 may inhibit neuroblastoma growth in children if treatment is initiated following intensive multimodality therapy, when residual disease is minimal.

Natural killer cell lymphoma: report of two pediatric cases, therapeutic options, and review of the literature

BACKGROUND

Natural killer (NK) cell lymphomas are rapidly fatal malignancies that to the authors' knowledge are rare in children. In the current study, the authors report the cases of two boys with NK cell lymphomas with refractory disease who both were salvaged with high dose chemotherapy and stem cell transplantation and compare these patients with those in the published experience.

METHODS

A comprehensive literature review was performed to identify other cases of pediatric patients with NK cell lymphomas, their treatment, and outcome.

RESULTS

One of the patients in the current study developed two recurrences and the other patient experienced early disease progression during front-line treatment. Both then were treated with high dose chemotherapy followed by stem cell rescue. At last follow-up, the patients remained free of disease at 15 months and 16 months, respectively, after transplantation (48 months and 22 months, respectively, from the time of diagnosis). In addition to the 2 patients in the current study, the authors found 13 pediatric patients reported in the literature to date. Of the 7 patients with localized (Stage I-II) disease, 5 patients (71%) were reported to be alive 1-107 months after diagnosis. Of the 6 patients with Stage IV disease, only the 2 patients who received high dose chemotherapy and stem cell rescue (33%) were alive at the time of last follow-up (at 30 months and 12 months, respectively). Including the patients reported in the current study, 9 of 15 children with NK cell lymphoma (all stages) (60%) were reported to be alive at the time of last follow-up.

CONCLUSIONS

Although pediatric NK cell lymphomas rapidly can become fatal, it appears that high dose chemotherapy followed by stem cell transplantation is effective therapy, especially in patients with advanced or resistant disease. Further follow-up is needed to determine whether this treatment approach will be curative.

Detection of MYCN gene amplification in neuroblastoma by fluorescence in situ hybridization: a pediatric oncology group study

To assess the utility of fluorescence in situ hybridization (FISH) for analysis of MYCN gene amplification in neuroblastoma, we compared this assay with Southern blot analysis using tumor specimens collected from 232 patients with presenting characteristics typical of this disease. The FISH technique identified MYCN amplification in 47 cases, compared with 39 by Southern blotting, thus increasing the total number of positive cases by 21%. The major cause of discordancy was a low fraction of tumor cells (< or =30% replacement) in clinical specimens, which prevented an accurate estimate of MYCN copy number by Southern blotting. With FISH, by contrast, it was possible to analyze multiple interphase nuclei of tumor cells, regardless of the proportion of normal peripheral blood, bone marrow, or stromal cells in clinical samples. Thus, FISH could be performed accurately with very small numbers of tumor cells from touch preparations of needle biopsies. Moreover, this procedure allowed us to discern the heterogeneous pattern of MYCN amplification that is characteristic of neuroblastoma. We conclude that FISH improves the detection of MYCN gene amplification in childhood neuroblastomas in a clinical setting, thus facilitating therapeutic decisions based on the presence or absence of this prognostically important biologic marker.

Treatment and outcome of 83 children with intraspinal neuroblastoma: the Pediatric Oncology Group experience

PURPOSE

To investigate whether the rate of neurologic recovery or the incidence of long-term sequelae differed for children with neuroblastoma (NB) initially treated with chemotherapy versus surgical decompression with laminectomy, we reviewed the Pediatric Oncology Group (POG) experience.

PATIENTS AND METHODS

A retrospective review of children diagnosed with intraspinal NB registered on POG NB Biology Protocol 9047 was performed. Survival, neurologic outcome, and orthopedic sequelae were evaluated according to age of the patient at diagnosis, stage of disease, duration and severity of neurologic symptoms, and therapeutic intervention.

RESULTS

Between May 1990 and January 1998, 83 children with intraspinal NB were entered onto the study. Five-year survival for this cohort of patients was 71% +/- 9%. Forty-three (52%) of the patients had neurologic symptoms at diagnosis. After treatment, six of 15 severely affected patients, who presented with paralysis, completely recovered neurologic function. Two of five patients with moderate deficits, consisting of paresis and bowel/bladder dysfunction, completely recovered neurologic function. Seventeen of 22 assessable children, who had mild symptoms comprised of paresis alone, fully recovered. Seven of 24 assessable patients who had undergone laminectomy developed scoliosis, whereas spinal deformities were only detected in one of 49 assessable patients managed without laminectomy (P =.001).

CONCLUSION

The frequency of complete neurologic recovery in children with intraspinal NB inversely correlated with the severity of the presenting neurologic deficits. The rate of neurologic recovery was similar for patients treated with chemotherapy compared to those managed with laminectomy. Fewer orthopedic sequelae were observed in the children managed with chemotherapy than were seen in children managed with laminectomy.

Natural killer cell lymphoma: report of two pediatric cases, therapeutic options, and review of the literature

BACKGROUND

Natural killer (NK) cell lymphomas are rapidly fatal malignancies that to the authors' knowledge are rare in children. In the current study, the authors report the cases of two boys with NK cell lymphomas with refractory disease who both were salvaged with high dose chemotherapy and stem cell transplantation and compare these patients with those in the published experience.

METHODS

A comprehensive literature review was performed to identify other cases of pediatric patients with NK cell lymphomas, their treatment, and outcome.

RESULTS

One of the patients in the current study developed two recurrences and the other patient experienced early disease progression during front-line treatment. Both then were treated with high dose chemotherapy followed by stem cell rescue. At last follow-up, the patients remained free of disease at 15 months and 16 months, respectively, after transplantation (48 months and 22 months, respectively, from the time of diagnosis). In addition to the 2 patients in the current study, the authors found 13 pediatric patients reported in the literature to date. Of the 7 patients with localized (Stage I-II) disease, 5 patients (71%) were reported to be alive 1-107 months after diagnosis. Of the 6 patients with Stage IV disease, only the 2 patients who received high dose chemotherapy and stem cell rescue (33%) were alive at the time of last follow-up (at 30 months and 12 months, respectively). Including the patients reported in the current study, 9 of 15 children with NK cell lymphoma (all stages) (60%) were reported to be alive at the time of last follow-up.

CONCLUSIONS

Although pediatric NK cell lymphomas rapidly can become fatal, it appears that high dose chemotherapy followed by stem cell transplantation is effective therapy, especially in patients with advanced or resistant disease. Further follow-up is needed to determine whether this treatment approach will be curative.

Expression of the putative tumour suppressor gene, p73, in neuroblastoma and other childhood tumours

BACKGROUND

The recently characterised p53 homologue, p73, has been mapped to chromosome 1p36, a region often found deleted in neuroblastoma. Although p73 has been implicated as a candidate tumour suppressor for neuroblastoma, mutations in the gene appear to be rare, thus suggesting other mechanisms for its aberrant behaviour.

PROCEDURE

We analysed p73 gene expression in a panel of primary neuroblastoma tumours and cell lines, as well as other tumours of childhood, using a reverse transcriptase-polymerase chain reaction assay.

RESULTS

Although low-level p73 expression was detected in 44/45 primary neuroblastoma tumours, no association with prognostic markers could be discerned. In no case was the level of p73 expression in the primary tumours as high as that observed in p73-expressing neuroblastoma cell lines. Expression of the p73 gene was also detected in 24/34 other childhood tumours.

CONCLUSION

Collectively, the data raise doubts over the role of this gene as a tumour suppressor in neuroblastoma.

Antiangiogenic therapy inhibits human neuroblastoma growth

BACKGROUND

Angiogenesis plays a crucial role in the progression and metastasis of malignant solid tumors. In many types of cancer, including neuroblastoma, high tumor vascularity correlates with poor outcome. Recently, a number of angiogenic inhibitors have been identified that had antitumor activity in preclinical studies.

PROCEDURE

To investigate the effect of the antiangiogenic agent TNP-470 on neuroblastoma tumor growth, we treated nude mice with TNP-470 after they were inoculated subcutaneously with 5 x 10(6) cells from the MYCN-amplified, human neuroblastoma cell line NBL-W-N.

RESULTS

TNP-470 did not significantly affect tumor growth when it was administered to mice with large tumors (>600 mm3). However, when TNP-470 was administered in the setting of microscopic disease 12 hr following tumor cell inoculation, treated mice had a significantly improved tumor-free survival at 12 weeks (P < 0.001), and overall survival at 45 weeks (P < 0.001), compared to control animals.

CONCLUSIONS

Our studies suggest that TNP-470 treatment may be most effective if it is administered in the setting of microscopic disease. We speculate that TNP-470 may inhibit neuroblastoma growth in children if treatment is initiated following intensive multimodality therapy, when residual disease is minimal.

Residential pesticide exposure and neuroblastoma

Neuroblastoma is the most common neoplasm in children under 1 year of age. We examined the relation between residential exposure to pesticides and neuroblastoma, using data from a case-control study of risk factors for neuroblastoma. Incident cases of neuroblastoma (N = 538) were identified through the Pediatric Oncology Group and the Children's Cancer Group. One age-matched control was identified for each case by random digit dialing. Telephone interviews with each parent collected information on residential exposure to pesticides. Pesticide use in both the home and garden were modestly associated with neuroblastoma [odds ratio (OR) = 1.6 (95% confidence interval [95% CI] = 1.0-2.3, and OR = 1.7 (95% CI = 0.9-2.1), respectively]. Compared with infants [OR = 1.0 (95% CI = 0.6-2.0)], stronger associations were found for garden pesticides in children diagnosed after 1 year of age [OR = 2.2 (95% CI = 1.3-3.6)], which suggests that pesticides may act through a mechanism more common for neuroblastomas in older children. There was no evidence of differential pesticide effects in subgroups of neuroblastoma defined by MYCN oncogene amplification or tumor stage.

Prognostic significance of EPHB6, EFNB2, and EFNB3 expressions in neuroblastoma

BACKGROUND

EPH family receptor tyrosine kinases and their ligand ephrins play pivotal roles in development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6), its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is predictive of favorable disease outcome of neuroblastoma (NB). When combined with TrkA expression, the expression of EPHB6, EFNB2, or EFNB3 predicts more accurately the disease outcome than each of the four variables alone.

PROCEDURE

Cox regression and Kaplan-Meier analyses were used to assess the prognostic significance of EPHB6, EFNB2, EFNB3, and TrkA expressions in NB without MYCN amplification.

RESULTS

High-level expression of EFNB3 or TrkA predicted favorable NB outcome of NB without MYCN amplification (p < 0.03). As found in the general NB population, EPHB6, EFNB2, or EFNB3 expression in combination with TrkA expression was significantly predictive of the disease outcome of normal MYCN NB (p < 0.01).

CONCLUSIONS

EPHB6, EFNB2, and EFNB3 expressions may permit further refinement of the prognostic stratification of NB into favorable and unfavorable groups.

Schwann cell-conditioned medium inhibits angiogenesis in vitro and in vivo

BACKGROUND

Neuroblastomas are biologically heterogeneous tumors that consist of two main cell populations: neuroblastic/ganglionic cells and Schwann cells. The amount of Schwannian stroma strongly impacts prognosis. Low tumor vascularity, localized stage, and favorable outcome are associated with tumors that are Schwannian stroma-rich/stroma-dominant.

PROCEDURE

To investigate if Schwann cells play a role in inhibiting angiogenesis in neuroblastoma tumors, we examined the ability of human Schwann cell-conditioned medium to affect bFGF- and VEGF-induced endothelial cell proliferation and migration, and in vivo angiogenesis.

RESULTS

Schwann cell-conditioned medium significantly inhibited bFGF- and VEGF-induced endothelial cell proliferation and migration. This effect appears to be specific for endothelial cells as smooth muscle cell and fibroblast proliferation were not inhibited by this medium. Schwann cell-conditioned medium also inhibited in vivo angiogenesis in rat corneal assays.

CONCLUSIONS

Schwann cells produce a potent inhibitor(s) of angiogenesis that may be responsible for the low level of vascularity and more benign clinical behavior of Schwannian stroma-rich/stroma-dominant neuroblastoma tumors. Studies to identify the inhibitor(s) are ongoing.

MYCN expression is not prognostic of adverse outcome in advanced-stage neuroblastoma with nonamplified MYCN

PURPOSE

The clinical significance of MYCN expression in children with neuroblastoma (NB) remains controversial. To determine the prognostic significance of MYCN expression in the absence of MYCN amplification, we analyzed MYCN mRNA and protein expression in tumors from 69 patients.

PATIENTS AND METHODS

Sixty-nine NB tumor samples with nonamplified MYCN from patients with stage C or D disease were obtained from the Pediatric Oncology Group Neuroblastoma Tumor Bank. MYCN mRNA was analyzed using a real-time reverse transcriptase polymerase chain reaction assay, and MYCN protein was examined by Western blot analyses.

RESULTS

The estimated 5-year event-free survival (EFS) and survival (S) rates plus SE for the cohort were 57% +/- 17% and 60% +/- 16%, respectively. Infants younger than 1 year had significantly higher rates of EFS and S than children >/= 1 year of age (P =.003 and P <.001, respectively); patients with stage C disease had better outcome than those with stage D NB (P <.001); and patients with hyperdiploid tumors had better outcome than those with diploid NB (P <.001). Surprisingly, outcome was slightly better for patients with high versus low levels of MYCN mRNA expression (4-year S, 70% +/- 13% v 50% +/- 16%; P =.290), and for patients with tumors that expressed MYCN protein (4-year S, 73% +/- 19% v 53% +/- 15%, respectively; P =.171).

CONCLUSION

High levels of MYCN expression are not prognostic of adverse outcome in patients with advanced-stage NB with nonamplified MYCN. A trend associating high levels of MYCN expression with improved outcome was observed.

Schwann cell-conditioned medium inhibits angiogenesis

Neuroblastomas are biologically heterogeneous tumors that consist of two main cell populations: neuroblastic/ganglionic cells and Schwann cells. The amount of Schwannian stroma strongly impacts prognosis, and favorable outcome is associated with tumors that are Schwannian stroma rich/stroma dominant. At the present time, there is controversy regarding the origin of Schwann cells in neuroblastoma tumors. However, recent studies have suggested that the Schwann cells in mature neuroblastoma tumors may be normal cells that produce soluble substances that enhance the survival and differentiation of neuroblastoma cell lines. Previously, we reported that in neuroblastoma, high vascular index correlated with clinically aggressive disease. In contrast, tumors with favorable histology and abundant Schwannian stroma had low tumor vascularity. As a first step toward investigating whether Schwann cells also play a role in inhibiting angiogenesis in neuroblastoma tumors, we examined the ability of conditioned medium collected from normal human Schwann cells to affect basic fibroblast growth factor- and vascular endothelial growth factor-induced endothelial cell proliferation and migration and in vivo angiogenesis. In vitro angiogenesis assays were also performed with conditioned medium collected from Schwann cells derived from a Schwannian stroma-dominant neuroblastoma tumor. Our results indicate that Schwann cells derived from either adult nerve or tumor tissue produce a potent inhibitor(s) of angiogenesis. Expression studies revealed tissue inhibitor of metalloproteinase (TIMP)-2 in conditioned medium collected from both normal and tumor-derived Schwann cells. In addition, TIMP-2 was detected in the cytoplasm of Schwann cells and ganglion cells in stroma-rich/stroma-dominant neuroblastoma tumors by immunohistochemistry studies. We postulate that the low level of vascularity and more benign clinical behavior of Schwannian stroma-rich/stroma-dominant neuroblastoma tumors result from the Schwann cell production of TIMP-2 and/or other inhibitors of angiogenesis.

Synergy between 5' and 3' flanking regions of the human tyrosine hydroxylase gene ensures specific, high-level expression in neuroblastoma cells

Factors regulating tyrosine hydroxylase (TH) gene transcription are of major importance in the studies of malignant and degenerative diseases of catecholamine-synthesizing tissues. In this study, we used transient transfection of a reporter gene to show that high-level, tissue-specific TH expression was only achieved when the reporter gene was cloned between a 5' TH promoter sequence (-513-+1), and, a 3' TH gene flanking sequence (end of exon 14-+976). We also show that TH mRNA expression level is closely linked to the expression level of the proto-oncogene, MYCN in neuroblastoma tumor cell lines. Taken together our data indicate that MYCN may regulate TH expression in neuroblastoma cells, but not through binding to the 5' or 3' TH gene flanking sequences used in our experiments.

Implications of EPHB6, EFNB2, and EFNB3 expressions in human neuroblastoma

Neuroblastoma (NB) is a common pediatric tumor that exhibits a wide range of biological and clinical heterogeneity. EPH (erythropoietin-producing hepatoma amplified sequence) family receptor tyrosine kinases and ligand ephrins play pivotal roles in neural and cardiovascular development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6) and its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is associated with low-stage NB (stages 1, 2, and 4S) and high TrkA expression. In this study, we showed that EFNB2 and TrkA expressions were associated with both tumor stage and age, whereas EPHB6 and EFNB3 expressions were solely associated with tumor stage, suggesting that these genes were expressed in distinct subsets of NB. Kaplan-Meier and Cox regression analyses revealed that high-level expression of EPHB6, EFNB2, and EFNB3 predicted favorable NB outcome (P<0.005), and their expression combined with TrkA expression predicted the disease outcome more accurately than each variable alone (P<0.00005). Interestingly, if any one of the four genes (EPHB6, EFNB2, EFNB3, or TrkA) was expressed at high levels in NB, the patient survival was excellent (>90%). To address whether a good disease outcome of NB was a consequence of high-level expression of a "favorable NB gene," we examined the effect of EPHB6 on NB cell lines. Transfection of EPHB6 cDNA into IMR5 and SY5Y expressing little endogenous EPHB6 resulted in inhibition of their clonogenicity in culture. Furthermore, transfection of EPHB6 suppressed the tumorigenicity of SY5Y in a mouse xenograft model, demonstrating that high-level expressions of favorable NB genes, such as EPHB6, can in fact suppress malignant phenotype of unfavorable NB.

Parental smoking and alcohol consumption and risk of neuroblastoma

Previous studies and animal evidence have suggested a relationship between parental tobacco or alcohol use and the risk of some childhood cancers, including neuroblastoma. A case-control study was conducted to investigate the relationship between parental tobacco smoking, alcohol consumption, and risk of neuroblastoma. Cases were children diagnosed with neuroblastoma over the period 1992-1994 at Children's Cancer Group and Pediatric Oncology Group institutions throughout the United States and Canada. One matched control was selected using random-digit dialing. Information on parental smoking and drinking history was obtained from 504 case and 504 control parents by telephone interview. Overall, there was no consistent pattern of association with parental smoking and alcohol consumption. For example, both maternal smoking and drinking during the period from 1 month before pregnancy through breastfeeding had adjusted odds ratios (ORs) of 1.1 [95% confidence interval (CI), 0.8-1.4]. There was no association with paternal smoking (OR, 1.2; 95% CI, 0.8-1.6) or paternal drinking 1 month before conception (OR, 1.0; 95% CI, 0.7-1.4). There was no consistent increase in risk by the amount of smoking or drinking during any time period relative to pregnancy. There was no suggestion of an increased risk when only one parent smoked. Smoking or drinking among both parents did not jointly increase the risk of neuroblastoma in their offspring. The child's age at diagnosis, stage, or MYCN oncogene amplification status did not materially alter the OR estimates. It is concluded that the results from this study do not indicate any evidence for a relationship between neuroblastoma and parental tobacco or alcohol use.

Natural history and biology of stage A neuroblastoma: a Pediatric Oncology Group Study

PURPOSE

To prospectively analyze the outcome of patients with Stage A neuroblastoma (NB) treated with surgery alone, especially with regard to the prognostic significance of age, tumor site, MYCN copy number, tumor cell ploidy, and histology.

PATIENTS AND METHODS

The clinical course of 329 patients with Stage A disease registered on the POG NB Biology Study #9047 between February, 1990 and October, 1997 were evaluated. Age, tumor site, MYCN copy number, tumor cell ploidy, and histology were analyzed for their impact on event-free survival (EFS) and survival (S).

RESULTS

The 5-year estimated EFS and S rates for the 329 patients were 91% (+/-3%) and 96% (+/-2%), respectively. The EFS rate was similar for infants younger than 12 months and children age 12 months or older, but age older than 12 months was predictive of lower S rates (P = 0.044). Patients with adrenal, abdominal non-adrenal, thoracic, and cervical tumors had similar S rates. The majority of patients had tumors with favorable biologic features, and only 3% had MYCN amplification. For infants with diploid tumors, the EFS rate was 82% (+/-16%), but effective therapy yielded an S rate of 100%. Rate of S was 80% (+/-26%) and 64% (+/-27%) for patients with unfavorable tumor histology and MYCN-amplified tumors, respectively.

CONCLUSION

The outcome for patients with Stage A NB treated with surgery alone is excellent. Although EFS and S rates were significantly worse for patients with MYCN-amplified tumors, a subset achieved long-term remission after surgery alone. For patients with Stage A and MYCN amplification, additional factors are needed to distinguish the patients who will achieve long-term remission with surgery alone from those who will develop recurrent disease.

Effectiveness of the angiogenesis inhibitor TNP-470 in reducing the growth of human neuroblastoma in nude mice inversely correlates with tumor burden

Angiogenesis plays an important role in the growth and metastasis of malignant tumors. We have previously reported that in children with neuroblastoma (NB), tumor vascularity directly correlates with metastatic disease, MYCN amplification, and poor outcome. The angiogenesis inhibitor TNP-470 has been shown to reduce the rate of NB growth in rodents with macroscopic tumors without ultimately impacting survival. To investigate whether TNP-470 could more effectively inhibit NB growth in animals with a low tumor burden, we treated 30 nude mice with minimal disease with this angiogenesis inhibitor (supplied by TAP Pharmaceuticals, Inc.). Therapy was initiated before tumors were clinically evident after s.c. inoculation of 5 x 10(6) cells from the MYCN-amplified NB cell line NBL-W-N. TNP-470 was administered 3 days/week, and after 12 weeks of treatment, 53% of the treated mice remained tumor free, whereas 100% of the control mice developed tumors (P < 0.0001). To further assess the relationship between the efficacy of TNP-470 treatment and tumor burden, TNP-470 was also administered s.c., 3 days/week, to mice with clinically evident small (<400 mm3; n = 15) and large (>400 mm3; n = 11) tumors. For animals with small tumors, the mean rate of growth was significantly decreased in the treated mice compared to the controls (P = 0.02). In contrast, there was no difference in the mean rate of tumor growth between animals with large tumors treated with TNP-470 and controls (P = 0.64). Our studies demonstrate that the effectiveness of TNP-470 inversely correlates with tumor burden. We speculate that TNP-470 may most effectively inhibit NB tumor growth in children with a low tumor burden.

Hormone and fertility drug use and the risk of neuroblastoma: a report from the Children's Cancer Group and the Pediatric Oncology Group

Previous epidemiologic studies have suggested an association between maternal sex hormone use during pregnancy, including infertility medication, and an increased risk of neuroblastoma in the offspring. The authors conducted a case-control interview study from 1992 to 1996 that included 504 children less than 19 years of age whose newly diagnosed neuroblastoma was identified by two national collaborative clinical trials groups in the United States and Canada, the Children's Cancer Group and the Pediatric Oncology Group. Controls, matched to cases on age, were identified by random digit dialing. No association was found for use of oral contraceptives before or during pregnancy (first trimester odds ratio (OR) = 1.0, 95% confidence interval (CI): 0.5, 2.1). The odds ratio was slightly elevated for history of infertility (OR = 1.4, 95% CI: 0.9, 2.1) and ever use of any infertility medication (OR = 1.2, 95% CI: 0.7, 2.2). Specifically, ever use of clomiphene was associated with a 1.6-fold increased risk (95% CI: 0.8, 3.0) but not periconceptionally or during the index pregnancy. A suggestive pattern was found for gender of the offspring, with an increased risk for males but not for females after exposure to oral contraceptives or clomiphene. This study did not find consistent and large increased risks for maternal use of hormones, but the suggestion of an association for male offspring requires further consideration.

Simplified single patch technique for the repair of atrioventricular septal defect

OBJECTIVE

Because of the complexity of traditional 1- and 2-patch techniques for the repair of complete atrioventricular septal defect, we modified our repair technique to avoid the use of any ventricular septal patch material. We report our prospective experience with this simplified 1-patch technique.

METHOD

Forty-seven consecutive patients between May 1995 and August 1998 underwent repair with the use of this technique without modification. Repair was done in all patients by direct suturing of the common atrioventricular valve leaflets to the crest of the ventricular septum. No division of valve leaflets was necessary. A single pericardial patch was used to close the defect in the atrial septal component. Follow-up included electrocardiography and echocardiographic assessment of ventricular function, atrioventricular valve function, and adequacy of the left ventricular outflow tract.

RESULTS

There were 2 deaths (4%), only 1 cardiac related, in the series. There were 17 male patients and 30 female patients. Mean age at repair was 5.6 months (median, 3.4 months). Associated lesions were repaired in 19 patients (40%). Mean follow-up was 1.85 years (median, 1.9 years). There was no heart block. There were no significant residual ventricular septal defects detected and no left ventricular outflow tract obstruction seen on echocardiography in any patient to date. Mitral valve status after operation was assessed as no incompetence in 13 patients (28%), minimal in 19 patients (40%), mild in 12 patients (26%), and moderate in 3 patients (6%).

CONCLUSION

The repair of complete atrioventricular septal defect by direct suturing of the atrioventricular valve leaflets to the crest of the ventricular septum with a single-patch technique greatly simplifies the repair and does not lead to left ventricular outflow tract obstruction nor interfere with valve function.

High-level expression of EPHB6, EFNB2, and EFNB3 is associated with low tumor stage and high TrkA expression in human neuroblastomas

Neuroblastoma (NB) is a common pediatric tumor of neural crest origin that is biologically and clinically heterogeneous. EPH family receptor tyrosine kinases and ephrin ligands play fundamental roles in neurodevelopmental processes. Recently, we found that NB cell lines expressed several EPHB and EFNB transcripts, which encode EPHB subgroup receptors and ephrin-B subgroup ligands, respectively. To explore the role of EPHB receptors and ephrin-B ligands in the biology of NB, we examined the expression of EPHB and EFNB transcripts in 47 primary NB specimens. Multiple EPHB and EFNB transcripts were expressed in all of the NB tumors examined, suggesting the involvement of these transcripts in modulating the biological behavior of NB. Higher levels of EPHB6, EFNB2, and EFNB3 expression were found in low-stage tumors (stage 1, 2, and 4S) than in advanced-stage tumors (stage 3 and 4; P = 0.0013, P = 0.0048, and P = 0.027, respectively). Expression of TrkA, a well-established prognostic marker of favorable NB, was positively correlated with EPHB6, EFNB2, and EFNB3 expression (P < 0.0001, P = 0.0019, and P = 0.0001, respectively). MYCN-amplified tumors expressed lower levels of EPHB6, EFNB2, EFNB3, and TrkA transcripts compared to nonamplified tumors (P = 0.0006, P = 0.0023, P = 0.0048, and P = 0.0001, respectively). These data suggest that high-level expression of EPHB6, EFNB2, and EFNB3 is associated with favorable NB and that low-level expression of EPHB6, EFNB2, and EFNB3 correlates with aggressive MYCN-amplified NB. Thus, EPHB6, EFNB2, and EFNB3 may have biological relevance in NB. Further investigation on the biology of these genes may help provide insight into the treatment of NB.

Long-term outcome of patients with intraspinal neuroblastoma

BACKGROUND

Chemotherapy, radiotherapy, and surgical decompression with laminectomy are effective therapeutic options in the treatment of cord compression from neuroblastoma (NB). We report the long-term outcome of patients with intraspinal NB treated with or without laminectomy at two large pediatric oncology centers.

PROCEDURE

We reviewed the medical records and radiographs of 26 children with intraspinal NB treated at Children's Memorial Hospital in Chicago, Illinois, between 1985 and 1994 or at St. Jude Children's Research Hospital in Memphis, Tennessee, between 1967 and 1992.

RESULTS

Twenty-four of the 26 patients are alive and disease-free (follow-up of 2-29 years; median, 10 years 2 months). Fifteen of the 23 patients with neurologic impairment underwent initial laminectomy. Nine of these 15 patients recovered neurologic function, including 3 patients who presented with paraplegia. Eleven of the 15 patients who underwent laminectomy have developed mild to severe spinal deformities. Eight patients with neurologic symptoms consequent to cord compression were treated with initial chemotherapy and/or surgery, but did not undergo laminectomy. Three patients with mild to moderate deficits recovered neurologic function. Four of 11 patients with intraspinal NB who did not undergo laminectomy have mild to severe scoliosis.

CONCLUSIONS

A low incidence of neurologic recovery was seen in patients with long-standing severe cord compression regardless of treatment modality. For patients with partial neurologic deficits, recovery was seen in most patients following chemotherapy or surgical decompression with laminectomy. A higher incidence of spinal deformities was seen in the patients treated with initial laminectomy.