Implementing a behavioral physical activity program in children and adolescent survivors of childhood cancer: a pilot randomized controlled trial.

Purpose We aimed to document the acceptability (enrollment rate) and feasibility (phone call delivery rate) of implementing a behavioral PA intervention over 12 weeks, in addition to documenting its effects on patient-reported outcomes and physical functioning. This study also describes the costs of carrying out a behavioral PA intervention. A total of 40 participants were randomized in a 1:1 ratio. The tailored behavioral PA intervention was developed based on the most recent PA guidelines in pediatric oncology and on the COM-B framework to enact PA behavior changes. The prescription (frequency, intensity, time and type (FITT)) was adjusted each week during the weekly support calls. The control group did not receive the intervention. 26 males and 14 females (13.6 years old on average and 2.9 years post-cancer treatment on average) participated in our study. The acceptability rate was 90.9% and the feasibility rate was > 85%. We found that 85% improved PA frequency, 80% improved PA intensity, 100% improved PA time, and 50.0% achieved the recommended PA guidelines. No adverse events were reported over the duration of the intervention. Physical function improved with longer 6-minute walk distances in the intervention group (465.8 ± 74.5 m) than in the control group (398.7 ± 92.9 m) (p = 0.016). PROs scores for all participants were within the limits of the normal range. The estimated cost per participant of carrying out this intervention was USD $126.57. Our 12-week behavioral PA intervention, based on the COM-B framework, was found to be acceptable, feasible and safe in childhood cancer survivors. This study is an important step in the right direction to make exercise standard practice in pediatric oncology.

Chronic pain in children and adolescents diagnosed with cancer: the challenge of mitigating the pain and the potential of integrating exercise into pain management.

BACKGROUND: Pain is one of the most common and distressing symptoms experienced by children and adolescents diagnosed with cancer. It is vital that children and adolescents receive adequate pain management early on in their cancer treatments to mitigate pain and cancer-related symptoms. Exercise training shows particular promise in the management of acute and chronic pain among children and adolescents diagnosed with cancer. METHODS: This position paper comes to outline the challenge of mitigating pain in children and adolescents diagnosed with cancer, and the potential benefits of integrating exercise training to the management of chronic pain in this population in need. RESULTS: Integrating exercise training into the care and pain management of children and adolescents diagnosed with cancer who have chronic pain would have the advantage of addressing several shortcomings of pain medication. Pain medication aims to temporarily manage or reduce pain; it does not have the potential to directly improve a patient's physical condition in the way that exercise training can. The current paucity of data available on the use of exercise training as a complementary treatment to pain medications to reduce chronic pain in children and adolescents diagnosed with cancer allows only for hypotheses on the effectiveness of this pain management modality. CONCLUSION: More research on this important topic is necessary and mitigating pain effectively while also reducing the use of opioid pain medication is an important goal shared by patients, their families, clinicians, and researchers alike. Future research in this area has great potential to inform clinical care, clinical care guidelines, and policy-making decisions for pain management in children and adolescents diagnosed with cancer who experience chronic pain.

A phase 1 trial of everolimus and bevacizumab in children with recurrent solid tumors.

BACKGROUND: The prognosis for children with recurrent solid tumors generally is poor. Targeting mammalian target of rapamycin (mTOR) and vascular endothelial growth factor A with everolimus and bevacizumab, respectively, synergistically improves progression-free survival and is well tolerated in adults with solid tumors. METHODS: In the current phase 1 study, a total of 15 children with recurrent or refractory solid tumors were treated with bevacizumab and everolimus to establish the maximum tolerated dose, toxicity, and preliminary antitumor response (ClinicalTrials.gov identifier NCT00756340). The authors also evaluated everolimus-mediated inhibition of the mTOR pathway in the peripheral blood mononuclear cells of treated patients. RESULTS: Tumors predominantly were soft tissue and/or bone sarcomas (8 cases) and brain tumors (5 cases). The first 2 patients enrolled at dose level 1 (10 mg/kg of bevacizumab and 4 mg/m2 of everolimus) experienced dose-limiting toxicities (DLTs). The next 5 patients were enrolled at dose level 0 (8 mg/kg of bevacizumab and 4 mg/m2 of everolimus), and DLTs occurred in 2 patients. The authors then modified the protocol to permit expansion of dose 0, and 8 additional patients were added, with no DLTs reported. Of all the patients, stable disease occurred in 4 patients (30.8%; median, 2 courses), and progressive disease occurred in 9 patients (69.2%). Overall survival was 0.59 years (95% CI, 0.24-1.05 years). The mTOR biomarker phospho-4EBP1 Thr/37/46 significantly decreased from baseline to day 27 in peripheral blood mononuclear cells (P = .045). Phospho-AKT levels also decreased from those at baseline. CONCLUSIONS: The maximum tolerated dose of cotreatment with bevacizumab and everolimus was 8 mg/kg of bevacizumab and 4 mg/m2 of everolimus in a 4-week cycle for children with recurrent solid tumors.

Phase I clinical trial of ifosfamide, oxaliplatin, and etoposide (IOE) in pediatric patients with refractory solid tumors.

Oxaliplatin, although related to cisplatin and carboplatin, has a more favorable toxicity profile and may offer advantages in combination regimens. We combined oxaliplatin, ifosfamide, and etoposide (IOE) and estimated the regimen's maximum tolerated dose (MTD) in children with refractory solid tumors. Dose-limiting toxicity (DLT) and MTD were assessed at 3 dose levels in a 21-day regimen: day 1, oxaliplatin 130 mg/m (consistent dose); days 1 to 3, ifosfamide 1200 mg/m/d (level 0) or 1500 mg/m/d (levels 1 and 2) and etoposide 75 mg/m/d (levels 0 and 1) or 100 mg/m/d (level 2). Course 1 filgrastim/pegfilgrastim was permitted after initial DLT determination, if neutropenia was dose limiting. Seventeen patients received 59 courses. Without filgrastim (n=9), DLT was neutropenia in 2 patients at dose level 1. No DLT was observed after adding filgrastim (n=8). There was no ototoxicity, nephrotoxicity >grade 1, or neurotoxicity >grade 2. One patient experienced a partial response and 9 had stable disease after 2 courses. In conclusion, the IOE regimen was well tolerated. Without filgrastim, neutropenia was dose limiting with MTD at ifosfamide 1200 mg/m/d and etoposide 75 mg/m/d. The MTD with filgrastim was not defined due to early study closure. Filgrastim allowed ifosfamide and etoposide dose escalation and should be included in future studies.

Subsequent malignant neoplasms in pediatric patients initially diagnosed with neuroblastoma.

BACKGROUND: Most prior studies evaluating subsequent malignant neoplasms (SMNs) in patients with neuroblastoma are restricted to long-term survivors and/or their treatment exposures. This study investigates SMNs in patients diagnosed with neuroblastoma at our institution. METHODS: Records of 646 patients treated for neuroblastoma at St Jude Children's Research Hospital between 1961 and 2005 were reviewed. Data from patients with SMNs were analyzed and the 20- and 30-year cumulative incidence of SMNs and standardized incidence ratio were calculated. RESULTS: Twenty-one patients had a SMN. The 20- and 30-year cumulative incidences of a SMN were 2.6%±0.7% and 4.6%±1.1%, respectively. The standardized incidence ratio was 8.3 (95% confidence interval, 5.0-13.0). Five patients developed a SMN within 5 years from diagnosis. The median latency for the development of acute myeloid leukemia/myelodysplastic syndrome (n=4), sarcomas (n=7), and carcinomas (n=5) were 3.6, 9, and 24.2 years, respectively. Nine patients died from their SMN, including all with acute myeloid leukemia/myelodysplastic syndrome. CONCLUSIONS: Patients with neuroblastoma have an increased risk of secondary neoplasia. Modification of risk-adapted therapies will likely alter the affected patient population and the incidence of SMNs. Future studies are necessary to link SMNs to treatment exposures and to evaluate the risk of SMNs beyond 30 years from diagnosis.

Intensity modulated radiation therapy provides excellent local control in high-risk abdominal neuroblastoma.

BACKGROUND: Locoregional failure is a significant concern in patients with high-risk abdominal neuroblastoma (NB) receiving radiotherapy. Locoregional control outcomes were studied in children with NB receiving intensity modulated radiotherapy (IMRT). PROCEDURE: Twenty children (11 females, 9 males) with NB (median age at diagnosis 3.4 years) receiving IMRT were analyzed for locoregional failure, outcomes, and toxicities. IMRT doses were 23.4 Gy (n = 12), 30 Gy (n = 1), 30.6 Gy (n = 5), and 36.0 Gy (n = 2) based on extent of resection. Five patients had tumors with MYCN amplification, and 19 had metastatic disease. All patients were treated consistently using reproducible immobilization techniques; physiological motion was assessed by 4D-CT, and target localization by cone-beam computed tomography. ICRU 62 volumetric conventions were employed based on institutional data for pediatric target volume and organ motion. RESULTS: No patient developed primary site infield or locoregional failure at a median follow-up of 2.2 years. Distant failure (median time to distant failure 1.6 years) occurred in the brain, lungs, or skeletal sites in eight patients, five of whom died. The 2-year event-free survival was 58.5 ± 13.3% and cumulative incidence of local and distant failures was 0% and 41.5 ± 11.9%, respectively. Asymptomatic loose stool during RT occurred in nearly all patients, but required no intervention. CONCLUSIONS: IMRT is feasible, safe in the short term, and yields excellent locoregional control. Despite subtotal resection in some cases, locoregional control appeared to be increased by conformal radiotherapy with ICRU 62-compliant volumes. Dose escalation beyond 30.6 Gy may be unnecessary with improved target volume coverage.

A single-arm pilot phase II study of gefitinib and irinotecan in children with newly diagnosed high-risk neuroblastoma.

BACKGROUND: Gefitinib potently inhibits neuroblastoma proliferation in vitro, and the gefitinib/irinotecan combination shows greater than additive activity against neuroblastoma xenografts. This Phase II pilot study estimated the rate of response to two courses of intravenous irinotecan plus oral gefitinib in children with untreated high-risk neuroblastoma. METHODS: Two courses of irinotecan [15 mg/m(2)/day (daily ×5)×2] were combined with 12 daily doses of gefitinib (112.5 mg/m(2)/day). Response was assessed after 6 weeks. A response rate >55% was sought. RESULTS: Of the 23 children enrolled, 19 were evaluable for response. Median age at diagnosis was 3.1 years (range, 18 days-12.7 years). Most patients were older than 24 months (n = 20; 87%), male (n = 18; 78%), white (n = 16; 70%), had INSS 4 disease (n = 19; 83%), and had adrenal primary tumors (n = 18; 78%); nine patients (39%) had amplified tumor MYCN. The toxicity of gefitinib/irinotecan was mild and reversible (nausea, 5/20; diarrhea, 8/20; vomiting, 7/20). Five patients had partial responses; 9 others had a 23%-60% decrease in primary tumor volume and/or improved MIBG scans or decreased bone or bone marrow tumor burden. Median (range) systemic irinotecan exposure (AUC) was 283 ng/ml*hr (range, 163-890 ng/ml*hr) and 28 ng/ml*hr (3.6-297 ng/ml*hr) for the active metabolite, SN-38. No relation was observed between response and tumor expression of EGFR, MRP2-4, ABCG2, and Pgp. CONCLUSIONS: Although the gefitinib/irinotecan combination was very tolerable and induced responses, it was not sufficiently active to warrant further investigation. Initial investigational studies of this type can preclude the necessity for larger, longer, and costlier trials.

Dose escalation of intravenous irinotecan using oral cefpodoxime: a phase I study in pediatric patients with refractory solid tumors.

BACKGROUND: Administration of an oral cephalosporin allowed advancement of the dosage of oral irinotecan. This study investigates whether administration of an oral cephalosporin increases the maximum tolerated dose (MTD) of intravenous irinotecan. PROCEDURE: Irinotecan was administered intravenously on Days 1-5 and Days 8-12 of a 21-day cycle with continuous oral cefpodoxime starting 2 days prior to irinotecan. Cohorts of 3-6 pediatric patients with refractory solid tumors were enrolled at 4 dosage levels, starting at the single-agent irinotecan MTD of 20 mg/m(2) /dose. RESULTS: The 17 evaluable patients received 39 courses of therapy. None of the patients treated with 20 mg/m(2) /dose experienced dose-limiting toxicity (DLT). One of six patients treated at 30 mg/m(2) /dose experienced dose-limiting neutropenia. Two of three patients treated with 45 mg/m(2) /dose and two of five treated with 40 mg/m(2) /dose experienced dose-limiting diarrhea, with associated dehydration and anorexia. Two unconfirmed partial responses were observed after one course in a patient with Ewing sarcoma and one with paraganglioma. A child with refractory neuroblastoma had disease stabilization through 12 courses of therapy. Median (range) systemic exposure to SN-38 at the MTD (30 mg/m(2) /dose) was 67 ng-h/mL (36 to 111 ng-h/mL). CONCLUSIONS: The MTD of intravenous irinotecan administered on a protracted schedule was increased by 50% from 20 to 30 mg/m(2) /dose with the addition of oral cefpodoxime. The most prominent DLT remained diarrhea. High interpatient variability in irinotecan pharmacokinetics was observed; however, SN-38 exposure at the MTD was greater than most reported exposures with the 20 mg/m(2) dosage.

A novel EWSR1-CREB3L1 fusion transcript in a case of small cell osteosarcoma.

Cellular morphology of small cell osteosarcoma, an aggressive variant of osteosarcoma, is similar to Ewing sarcoma, but its molecular pathogenesis is largely unknown. We report the case of a 12-year-old girl with multifocal small cell osteosarcoma positive for the Ewing sarcoma breakpoint region 1 (EWSR1) gene rearrangement by interphase fluorescent in situ hybridization and negative for EWSR1-FLI1, EWSR1-ERG, and EWSR1-WT1 fusion transcripts by reverse transcriptase PCR. Rapid amplification of cDNA ends revealed exon 6 of the cAMP-responsive element binding protein 3-like 1 gene (CREB3L1, also known as "OASIS," NM_52854.2) fused in-frame to the EWSR1 exon 11, consistent with the EWSR1-CREB3L1 fusion transcript expressed in tumor tissue. The corresponding chimeric gene was confirmed by amplification and subsequent sequencing of the genomic breakpoint between introns 11 and 5 of EWSR1 and CREB3L1, respectively. An ∼70 kDa product in the tumor tissue lysate reacted with the CREB3L1 carboxyterminal antibody, consistent with a 656-amino acid predicted chimeric protein. Immunohistochemistry with the same antibody showed signal translocation from the physiologic perinuclear compartment observed in glia and unrelated osteoblasts to nuclei of tumor cells, consistent with the likely function of EWSR1-CREB3L1 as a transcriptional regulator predicted by its structure. This is the first report of a fusion transcript in osteogenic sarcoma; it demonstrates a relation between molecular mechanisms of small cell osteogenic and Ewing sarcomas. The 3'-end partner and the inferred structure of EWSR1-CREB3L1, however, are different from those of Ewing sarcoma, suggesting different targets of the new oncogene.

A scoping review to map the evidence of physical activity interventions in post-treatment adolescent and young adult cancer survivors.

PURPOSE: This scoping review describes and synthesizes previously reported data to document physical activity (PA) interventions in adolescents and young adult (AYA) cancer survivors and to explore whether PA interventions tested to date improve survivors' health outcomes. METHODS: A search of the literature was conducted in PubMed, CINAHL, EMBASE, Web of Science and Cochrane Library following the PRISMA-ScR statement. We included all original studies (n = 8) investigating PA interventions in AYA cancer survivors. RESULTS: This review showed that PA interventions were feasible and acceptable in AYA cancer survivors. PA interventions were individualized and mainly aerobic in nature. Studies examining the effects of PA interventions on survivors' health evaluated physical and mental health outcomes. CONCLUSIONS: Our scoping review maps the current evidence of PA interventions and highlights the paucity of data in this area of investigation, obviating how much work remains to be done to demonstrate the potential benefits of PA on AYA cancer survivors' health outcomes.

Using social exchange theory to guide successful study recruitment and retention.

Participant attrition (withdrawal or loss after entering a study) is a major threat to the completion of valid studies. It can result in systematic error (selection bias), thus decreasing the statistical power of studies and limiting the generalisability of study findings. This paper demonstrates how key social exchange theory principles form the theoretical context for our practice, which, in turn enables us to form enduring relationships with study participants.

Attendance at National Cancer Institute and Children's Oncology Group Facilities for Children, Adolescents, and Young Adults with Cancer in Pennsylvania: A Population-Based Study.

Purpose: Adolescents and young adults (AYAs) with cancer are a vulnerable population with decreased attendance at National Cancer Institute (NCI) comprehensive cancer centers and Children's Oncology Group (COG) facilities. Decreased attendance at NCI/COG facilities has been associated with poor cancer outcomes. The objective of this study was to evaluate cancer care patterns of AYAs compared with children, within Pennsylvania, and factors associated with attending an NCI/COG facility. Methods: Data from the Pennsylvania Cancer Registry between 2010 and 2015 for patients aged 0-39 years at cancer diagnosis were used. Primary analyses focused on age at diagnosis, insurance status, race, ethnicity, gender, cancer type, stage, diagnosis year, and distance to the NCI/COG facility. The primary outcome was receipt of care at an NCI/COG facility. Odds ratios (ORs) were calculated using multivariable logistic regression models. Sensitivity analyses were conducted to test and estimate robustness. Results: A sample of 15,002 patients, ages 0-39, was obtained, including 8857 patients (59%) who attended an NCI/COG facility. Patients were significantly less likely to attend an NCI/COG facility if they were aged 31-39 years (OR 0.054, 95% confidence interval [CI] 0.04-0.07), non-White (OR 0.890, 95% CI 0.80-0.99), Hispanic (OR 0.701, 95% CI 0.59-0.83), female (OR 0.915, 95% CI 0.84-1.00), had Medicaid insurance (OR 0.836, 95% CI 0.75-0.93), and lived further from an NCI/COG facility. Sensitivity analyses largely corroborated the performed estimates. Conclusions: AYAs with cancer in Pennsylvania have disproportionate attendance at specialized NCI/COG facilities across a variety of demographic domains. Enhancing the attendance of AYAs with cancer at these specialized centers is crucial to improve cancer outcomes.

Pediatric cancers in the new millennium: dramatic progress, new challenges.

Over the past 50 years, great strides have been made in diagnosis, treatment, and survival of childhood cancer. In the 1960s the probability of survival for a child with cancer was less than 25%, whereas today it may exceed 80%. This dramatic change has occurred through significant and steady progress in our understanding of tumor biology, creation of specialized multidisciplinary care teams, incremental improvements in therapy, establishment of specialized centers with research infrastructure to conduct pivotal clinical studies, and the evolution of a cooperative group mechanism for clinical research. Most children with cancer in the United States, Europe, and Japan receive appropriate diagnosis and treatment, although access is limited in developing countries. The price of success, however, is the growing population of survivors who require medical and psychosocial follow-up and treatment for the late effects of therapy. Here we review the progress made in pediatric oncology over the past 3 decades and consider the new challenges that face us today.

First Nations people's challenge in managing coronary artery disease risk.

First Nations peoples bring a particular history and cultural perspective to healing and well-being that significantly influences their health behaviors. The authors used grounded theory methods to describe and explain how ethnocultural affiliation and gender influence the process that 22 First Nations people underwent when making lifestyle changes related to their coronary artery disease (CAD) risk. The transcribed interviews revealed a core variable, meeting the challenge. Meeting the challenge of CAD risk management was influenced by intrapersonal, interpersonal (relationships with others), extrapersonal (i.e., the community and government), sociodemographic, and gendered factors. Salient elements for the participants included their beliefs about origins of illness, the role of family, challenges to accessing information, financial and resource management, and the gendered element of body image. Health care providers need to understand the historical, social, and culturally embedded factors that influence First Nations people's appraisal of their CAD.

The telephone interview is an effective method of data collection in clinical nursing research: a discussion paper.

There are varying points of view regarding the advisability and utility of using the telephone to conduct research interviews. When undertaking the Women's Recovery from Sternotomy Study, we found the telephone was an effective mechanism for data collection. Our aim is to identify the advantages and challenges of using the telephone as a mechanism for data collection in clinical nursing research. The potential benefits associated with using telephone interviews as a mechanism of data collection include (a) using economic and human resources efficiently, (b) minimizing disadvantages associated with in-person interviewing, (c) developing positive relationships between researchers and participants, and (d) improving quality of data collection. The potential challenges to telephone interviewing include (a) maintaining participant involvement, (b) maintaining clear communication, (c) communicating with participants who offer extraneous information, (d) encountering participants with health concerns, and (e) communicating with a third party. Telephone interviewing can be an effective method of data collection when interviewers understand the potential benefits as well as challenges. We offer solutions to the identified challenges and make pragmatic recommendations to enhance researcher success based on the current literature and our research practice. Supportive training for interviewers, effective communication between interviewers and with research participants, and standardized telephone follow-up procedures are needed to ensure successful telephone data collection. We have found our 'Manual of Operations' to be an effective tool that assists research assistants to meet the requirements for successful telephone interviewing.

Repeat nephron-sparing surgery for children with bilateral Wilms tumor.

BACKGROUND: Renal insufficiency is a significant complication of Wilms tumor treatment in the 5% with bilateral disease. Nephron-sparing surgery (NSS) is recommended after neoadjuvant chemotherapy initially. However, the role of NSS in recurrent disease is unknown. We reviewed our experience to assess the feasibility and oncologic and functional outcomes of repeat NSS for children with recurrent disease. METHODS: A retrospective review was performed of all children treated at our institution for bilateral, favorable histology (FH) Wilms tumor. Patients undergoing repeat NSS for locally recurrent disease were identified. The outcomes evaluated included tumor recurrence, renal function, and patient survival. RESULTS: Since 2001, 36 children with bilateral FH Wilms tumor have been treated at our institution. Eight patients (22%) underwent repeat NSS for locally recurrent disease. Two patients had a second local recurrence and underwent a third NSS. Six patients are alive without disease (75%) with an average follow-up of 4.5years. Two patients have died, each with blastemal-predominant histology at repeat NSS. The surviving patients have normal renal function, although two patients require medical management of hypertension. CONCLUSIONS: Our experience suggests that repeat NSS for local recurrence of FH bilateral Wilms tumor is feasible and affords acceptable oncologic outcome with preservation of renal function. However, more aggressive therapy may be required for patients whose recurrence has blastemal-predominant histology, given the poor outcome for these patients in our series.

Phase I trial of a novel anti-GD2 monoclonal antibody, Hu14.18K322A, designed to decrease toxicity in children with refractory or recurrent neuroblastoma.

PURPOSE: The addition of immunotherapy, including a combination of anti-GD2 monoclonal antibody (mAb), ch14.18, and cytokines, improves outcome for patients with high-risk neuroblastoma. However, this therapy is limited by ch14.18-related toxicities that may be partially mediated by complement activation. We report the results of a phase I trial to determine the maximum-tolerated dose (MTD), safety profile, and pharmacokinetics of hu14.18K322A, a humanized anti-GD2 mAb with a single point mutation (K322A) that reduces complement-dependent lysis. PATIENTS AND METHODS: Eligible patients with refractory or recurrent neuroblastoma received escalating doses of hu14.18K322A ranging from 2 to 70 mg/m(2) per day for 4 consecutive days every 28 days (one course). RESULTS: Thirty-eight patients (23 males; median age, 7.2 years) received a median of two courses (range, one to 15). Dose-limiting grade 3 or 4 toxicities occurred in four of 36 evaluable patients and were characterized by cough, asthenia, sensory neuropathy, anorexia, serum sickness, and hypertensive encephalopathy. The most common non-dose-limiting grade 3 or 4 toxicities during course one were pain (68%) and fever (21%). Six of 31 patients evaluable for response by iodine-123 metaiodobenzylguanidine score had objective responses (four complete responses; two partial responses). The first-course pharmacokinetics of hu14.18K322A were best described by a two-compartment linear model. Median hu14.18K322A α (initial phase) and ß (terminal phase) half-lives were 1.74 and 21.1 days, respectively. CONCLUSION: The MTD, and recommended phase II dose, of hu14.18K322A is 60 mg/m(2) per day for 4 days. Adverse effects, predominately pain, were manageable and improved with subsequent courses.

Rapamycin increases neuroblastoma xenograft and host stromal derived osteoprotegerin inhibiting osteolytic bone disease in a bone metastasis model.

PURPOSE: Osteoprotegerin (OPG) is a decoy receptor for the Receptor of NF-κB (RANK) ligand that can inhibit osteoclastogenesis. Previous studies have suggested that Mammalian Target of Rapamycin (mTOR) inhibition upregulates OPG production. We tested the hypothesis that the mTOR inhibitor rapamycin could inhibit neuroblastoma bone metastases through its action on OPG. EXPERIMENTAL DESIGN: An orthotopic model of bone metastasis was established. Mice with established disease were subsequently treated with rapamycin (5mg/kg IP daily) or vehicle control (DMSO 1:1000). X-rays were obtained twice a week to detect pathologic fractures. Serum OPG levels were measured by ELISA after two weeks of treatment. RESULTS: Mice with bone disease receiving rapamycin had increased serum levels of OPG in the CHLA-20 mice compared to controls (36.89 pg/mL ± 3.90 vs 18.4 pg/mL ± 1.67, p=0.004) and NB1691 tumor-bearing groups (46.03 ± 2.67 pg/mL vs 17.96 ± 1.84pg/mL, p=0.001), and a significantly longer median time to pathologic fractures with CHLA-20 (103 days vs 74.5 days, p=0.014) and NB1691 xenografts. CONCLUSION: In a xenograft model, increased OPG expression correlated with a delay to pathologic fracture suggesting a potential role for mTOR inhibitors in the treatment of neuroblastoma bone metastases.

Margin status and tumor recurrence after nephron-sparing surgery for bilateral Wilms tumor.

PURPOSE: Nephron-sparing surgery (NSS) has been advocated for patients with bilateral Wilms tumor (BWT). We sought to determine whether margin status impacted local tumor recurrence. METHODS: A retrospective review of patients undergoing NSS for BWT from November 1999 to March 2009 at our institution in which local recurrence rates based on margin status were compared. RESULTS: Of 21 patients, five (23.8%) had positive margins. These and 2 (9.5%) with focal anaplasia received flank XRT. Seven (33%) patients developed recurrent disease, a mean of 18.0 (range 1.3-39.9) months after NSS. Recurrence rates were similar in patients with positive and negative margins (1/5 [20%] vs 6/16 [37.5%]; p = 0.47). Hypertension occurred more frequently in patients who received XRT (57.1% vs 28.6%). At a median follow-up of 28.6 months (range 5.2-142.3), 19 patients are alive, without evidence of disease; one patient (with a positive margin at initial NSS) died of metastatic anaplastic WT and another died of a brain tumor. One patient, with multiple risk factors, developed renal failure. CONCLUSIONS: In our experience, local recurrence rates after NSS were not affected by surgical margin status although all patients with positive margins received XRT. These results support the aggressive use of NSS for patients with BWT.

Establishment and characterization of the first pediatric adrenocortical carcinoma xenograft model identifies topotecan as a potential chemotherapeutic agent.

PURPOSE: Pediatric adrenocortical carcinoma (ACC) is a rare and highly aggressive malignancy. Conventional chemotherapeutic agents have shown limited utility and are largely ineffective in treating children with advanced ACC. The lack of cell lines and animal models of pediatric ACC has hampered the development of new therapies. Here we report the establishment of the first pediatric ACC xenograft model and the characterization of its sensitivity to selected chemotherapeutic agents. EXPERIMENTAL DESIGN: A tumor from an 11-year-old boy with previously untreated ACC was established as a subcutaneous xenograft in immunocompromised CB17 scid(-/-) mice. The patient harbored a germline TP53 G245C mutation, and the primary tumor showed loss of heterozygosity with retention of the mutated TP53 allele. Histopathology, DNA fingerprinting, gene expression profiling, and biochemical analyses of the xenograft were conducted and compared with the primary tumor and normal adrenal cortex. The second endpoint was to assess the preliminary antitumor activity of selected chemotherapeutic agents. RESULTS: The xenograft maintained the histopathologic and molecular features of the primary tumor. Screening the xenograft for drug responsiveness showed that cisplatin had a potent antitumor effect. However, etoposide, doxorubicin, and a panel of other common cancer drugs had little or no antitumor activity, with the exception of topotecan, which was found to significantly inhibit tumor growth. Consistent with these preclinical findings, topotecan as a single agent in a child with relapsed ACC resulted in disease stabilization. CONCLUSION: Our study established a novel TP53-associated pediatric ACC xenograft and identified topotecan as a potentially effective agent for treating children with this disease.