Critical elements of pediatric neuroblastoma surgery.

Neuroblastoma (NB) is the most common solid extracranial malignancy of childhood with an incidence of 1 per 100,000 in the United States compromising approximately 10 % of childhood cancer. Unfortunately, patients with high-risk NG continue to have long-term survival less than 50 %. Both Children's Oncology Group and the International Society of Paediatric Oncology have demonstrated the important role of surgery in the treatment of high-risk NB. Herein, we compose the results of an extensive literature review as well as expert opinion from leaders in pediatric surgical oncology, to present the critical elements of effective surgery for high-risk neuroblastoma.

Outcomes of Wilms tumor therapy in Lilongwe, Malawi, 2016-2021: Successes and ongoing research priorities.

INTRODUCTION: Wilms tumor therapy in low- and middle-income countries (LMICs) relies on treatment protocols adapted to resource limitations, but these protocols have rarely been evaluated in real-world settings. Such evaluations are necessary to identify high-impact research priorities for clinical and implementation trials in LMICs. The purpose of this study was to identify highest priority targets for future clinical and implementation trials in sub-Saharan Africa by assessing outcomes of a resource-adapted treatment protocol in Malawi. METHODS: We conducted a retrospective cohort study of children treated for Wilms tumor with an adapted SIOP-backbone protocol in Lilongwe, Malawi between 2016 and 2021. Survival analysis assessed variables associated with poor outcome with high potential for future research and intervention. RESULTS: We identified 136 patients, most commonly with stage III (n = 35; 25.7%) or IV disease (n = 35; 25.7%). Two-year event-free survival (EFS) was 54% for stage I/II, 51% for stage III, and 13% for stage IV. A single patient with stage V disease survived to 1 year. Treatment abandonment occurred in 36 (26.5%) patients. Radiotherapy was indicated for 55 (40.4%), among whom three received it. Of these 55 patients, 2-year EFS was 31%. Of 14 patients with persistent metastatic pulmonary disease at the time of nephrectomy, none survived to 2 years. Notable variables independently associated with survival were severe acute malnutrition (hazard ratio [HR]: 1.9), increasing tumor stage (HR: 1.5), and vena cava involvement (HR: 3.1). CONCLUSION: High-impact targets for clinical and implementation trials in low-resource settings include treatment abandonment, late presentation, and approaches optimized for healthcare systems with persistently unavailable radiotherapy.

Association of Intercostal Nerve Cryoablation During Nuss Procedure With Complications and Costs.

BACKGROUND: Intercostal nerve cryoablation with the Nuss procedure has been shown to decrease opioid requirements and hospital length of stay; however, few studies have evaluated the impact on complications and hospital costs. METHODS: A retrospective cohort study was performed for all Nuss procedures at our institution from 2016 through 2020. Outcomes were compared across 4 pain modalities: cryoablation with standardized pain regimen (n = 98), patient-controlled analgesia (PCA; n = 96), epidural (n = 36), and PCA with peripheral nerve block (PNB; n = 35). Outcomes collected included length of stay, opioid use, variable direct costs, and postoperative complications. Univariate and multivariate hierarchical regression analysis was used to compare outcomes between the pain modalities. RESULTS: Cryoablation was associated with increased total hospital cost compared with PCA (cryoablation, $11 145; PCA, $8975; P < .01), but not when compared with epidural ($9678) or PCA with PNB ($10 303). The primary driver for increased costs was operating room supplies (PCA, $2741; epidural, $2767; PCA with PNB, $3157; and cryoablation, $5938; P < .01). With multivariate analysis, cryoablation was associated with decreased length of stay (-1.94; 95% CI, -2.30 to -1.57), opioid use during hospitalization (-3.54; 95% CI, -4.81 to -2.28), and urinary retention (0.13; 95% CI, 0.05-0.35). CONCLUSIONS: Cryoablation significantly reduces opioid requirements and length of stay relative to alternative modalities, but it was associated with an increase in total hospital costs relative to PCA, but not epidural or PCA with PNB. Cryoablation was not associated with allodynia or slipped bars requiring reoperation.

Comparison of subcutaneous analgesic system and epidural analgesia for postoperative pain control in open pediatric oncology operations: A randomized controlled trial.

PURPOSE: Children undergoing open oncologic surgery can have significant post-operative pain. The purpose of this trial was to compare a surgeon-placed subcutaneous analgesic system (SAS) to epidural analgesia. METHODS: Single center randomized controlled trial including children ≤18 years undergoing open tumor resection between October 2018 and April 2021. Randomization to SAS or epidural was done preoperatively and perioperative pain management was standardized. Families were blinded to the modality. Comparisons of oral morphine equivalents (OME) and pain scores for three postoperative days, clinical outcome parameters, and parental satisfaction following unblinding were completed using non-parametric analyses. RESULTS: Of 36 patients (SAS 18, Epidural 18), median age was 5 years (range <1-17). The Epidural cohort had less OME demand on postoperative day one (SAS 0.76 mg/kg, Epidural 0.11 mg/kg; p<0.01) and two (SAS 0.48 mg/kg, Epidural 0.07 mg/kg, p = 0.03). Pain scores were similar on postoperative days 1-3 (0-2 in both groups). The Epidural cohort had more device complications (SAS 11%, Epidural 50%; p = 0.03) and higher urinary catheter use (SAS 50%, Epidural 89%; p = 0.03). More than 80% of parents would use the same device in the future (SAS 100%, Epidural 84%, p = 0.23). CONCLUSION: For children undergoing open oncologic abdominal or thoracic surgery, early post-operative pain control appears to be better with epidural analgesia; however, SAS has decreased incidence of device complications and urinary catheter use. Parental satisfaction is excellent with both modalities. SAS could be considered as an alternative to epidural, especially in settings when epidural placement is not available or contraindicated. TYPE OF STUDY: Treatment study, Randomized controlled trial. LEVEL OF EVIDENCE: Level 1.

Angiosarcoma of the Pancreas in a Pediatric Patient With an Activating KDR-Internal Tandem Duplication: A Case Report and Review of the Literature.

Pancreatic angiosarcoma is an exceedingly rare malignancy accounting for <1% of pancreatic neoplasms. A very limited number of pancreatic angiosarcomas have been reported in the literature without any cases described in children. We present the case of a 17-year-old female diagnosed with angiosarcoma of the pancreas following pancreaticoduodenectomy for a pancreatic mass, initially presumed to be a solid pseudopapillary neoplasm of the pancreas. The angiosarcoma was found to have a novel activating internal tandem duplication in the KDR gene (KDR-internal tandem duplication). We discuss the current literature on this disease process. This is the first reported case of pancreatic angiosarcoma in a pediatric patient and the first with an activating KDR-internal tandem duplication.

A Novel Standard for Systematic Reporting of Neuroblastoma Surgery: The International Neuroblastoma Surgical Report Form (INSRF): A Joint Initiative by the Pediatric Oncological Cooperative Groups SIOPEN∗, COG∗∗, and GPOH∗∗∗.

OBJECTIVE: To create the first structured surgical report form for NBL with international consensus, to permit standardized documentation of all NBL-related surgical procedures and their outcomes. SUMMARY OF BACKGROUND DATA: NBL, the most common extracranial solid malignant tumor in children, covers a wide spectrum of tumors with significant differences in anatomical localization, organ or vessel involvement, and tumor biology. Complete surgical resection of the primary tumor is an important part of NBL treatment, but maybe hazardous, prone to complications and its role in high-risk disease remains debated. Various surgical guidelines exist within the protocols of the different cooperative groups, although there is no standardized operative report form to document the surgical treatment of NBL. METHODS: After analyzing the treatment protocols of the SIOP Europe International Neuroblastoma Study Group, Children's Oncology Group, and Gesellschaft fuer Paediatrische Onkologie und Haematologie - German Association of Pediatric Oncology and Haematology pediatric cooperative groups, important variables were defined to completely describe surgical biopsy and resection of NBL and their outcomes. All variables were discussed within the Surgical Committees of SIOP Europe International Neuroblastoma Study Group, Children's Oncology Group, and Gesellschaft fuer Paediatrische Onkologie und Haematologie - German Association of Pediatric Oncology and Haematology. Thereafter, joint meetings were organized to obtain intercontinental consensus. RESULTS: The "International Neuroblastoma Surgical Report Form" provides a structured reporting tool for all NBL surgery, in every anatomical region, documenting all Image Defined Risk Factors and structures involved, with obligatory reporting of intraoperative and 30 day-postoperative complications. CONCLUSION: The International Neuroblastoma Surgical Report Form is the first universal form for the structured and uniform reporting of NBL-related surgical procedures and their outcomes, aiming to facilitate the postoperative communication, treatment planning and analysis of surgical treatment of NBL.

Variations in Nuss Procedure Operative Techniques and Complications: A Retrospective Review.

INTRODUCTION: The Nuss procedure is the most common and preferred operative correction of pectus excavatum. Surgeon preference and patient factors can result in variations in Nuss procedure technique. We hypothesize that certain techniques are associated with increased risk of complications. MATERIALS AND METHODS: We performed a single-center retrospective review of Nuss operations from 2016 to 2020. Variations in intraoperative techniques included sternal elevator (SE) use, number of bars placed, and usage of bilateral stabilizing sutures. Patient demographics, intraoperative data, and postoperative outcomes were reported as median with interquartile ranges or percentages. Statistical significance (p < 0.05) was determined with Wilcoxon's rank-sum and chi-square tests. Multivariate analysis was performed to control for introduction of intercostal nerve cryoablation and surgeon volume, and reported as odds ratio with 95% confidence interval. RESULTS: Two hundred and sixty-five patients were identified. Patients repaired with two bars were older with a larger Haller index (HI). Patient demographics were not significantly different for SE or stabilizing suture use. Placement of two bars was associated with significantly increased risk of readmission. Similarly, SE use was associated with increased risk of pleural effusion and readmission. Finally, the use of bilateral stabilizing sutures resulted in less frequent slipped bars without statistical significance. CONCLUSION: Older patients with a larger HI were more likely to need two bars placed to repair pectus excavatum. Placement of multiple bars and SE use are associated with significantly higher odds of certain complications.

Lessons learned from value-based pediatric appendectomy care: A shared savings pilot model.

PURPOSE: We aim to assess the healthcare value achieved from a shared savings program for pediatric appendectomy. METHODS: All appendectomy patients covered by our health plan were included. Quality targets were 15% reduction in time to surgery, length of stay, readmission rate, and patient satisfaction. Quality targets and costs for an appendectomy episode in two 6-month performance periods (PP1, PP2) were compared to baseline. RESULTS: 640 patients were included (baseline:317, PP1:167, PP2:156). No quality targets were met in PP1. Two quality targets were met during PP2: readmission rate (-57%) and patient satisfaction. No savings were realized because the cost reduction threshold (-9%) was not met during PP1 (+1.7%) or PP2 (-0.4%). CONCLUSIONS: Payer-provider partnerships can be a platform for testing value-based reimbursement models. Setting achievable targets, identifying affectable quality metrics, considering case mix index, and allowing sufficient time for interventions to generate cost savings should be considered in future programs.

Integration of a dedicated management protocol in the care of pediatric liver cancer: From specialized providers to complication reduction.

INTRODUCTION: Up to a third of children undergoing partial hepatectomy for primary hepatic malignancies experience at least one perioperative complication, with a presumed deleterious effect on both short- and long-term outcomes. We implemented a multidisciplinary treatment protocol in the management of these patients in order to improve complication rates following partial hepatectomy. METHODS: A retrospective chart review was completed for all patients < 18 years of age who underwent liver resection at our institution between 2002 and 2019 for primary hepatic cancer. Demographic, intraoperative, postoperative, pathologic, and outcome data were analyzed for perioperative complications using the CLASSIC and Clavien-Dindo (CD) scales, event-free survival (EFS) and overall survival (OS). RESULTS: A total of 73 patients were included in the analysis with 33 prior-to and 40 after dedicated provider protocol implementation. Perioperative complication rates decreased from 52% to 20% (p = 0.005) with major complications going from 18% to 10% (p = 0.31). On multivariable logistic regression, protocol implementation was associated with a reduction in any (OR 0.29 [95% CI 0.09 - 0.89]) but not major complications. On multivariate cox models, post protocol implementation was associated with improved event free survival (EFS) (HR 0.19 (0.036 - 0.195). Among patients with a diagnosis of hepatoblastoma (n = 62), the occurrence of a major perioperative complication was associated with a worse EFS (HR=5.45, p = 0.03) on multivariate analysis, however this did not translate into an impact on overall survival. CONCLUSIONS: Our results demonstrate that, for children with primary liver malignancies, a dedication of patients to high-volume surgeons can improve rates of complications of liver resections and may improve the oncological outcome of hepatoblastoma.

Characteristics of benign neuroblastic tumors: Is surgery always necessary?

PURPOSE: Ganglioneuroma (GN) and ganglioneuroblastoma-intermixed (GNB-I) represent benign variants of neuroblastic tumors in children; however, differentiating from more aggressive histological variants of GNB including the nodular subtype (GNB-N) prior to resection can be challenging, even with biopsy. Currently, no standard treatment guidelines exist. The purpose of this study was to identify pre-operative characteristics of benign neuroblastic tumors and evaluate outcomes for patients who underwent surgical resection or observation. METHODS: Retrospective chart review of children treated at a single institution between 2009 and 2019 for non-metastatic tumor with a tissue diagnosis of GN, GNB-N or GNB-I. Demographics, imaging, labs, operative details and outcomes were recorded and analyzed. RESULTS: Of 53 patients, 45% were male. The most common tumor location was abdomen (49%), followed by thorax (34%). Forty-five percent had at least one image defined risk factor. Biopsy was performed in 32% (17/53) and upfront surgery in 68% (36/53). Three patients (3/53, 5.6%) with biopsy demonstrating GN tumors were observed due to high surgical risk. Pathology of resected specimens demonstrated GN in 52% (26/50) and GNB-I or GNB-N in 48% (24/50). The majority of GNB tumors (75% (18/24) were GNB-I and 25% (6/24) were GNB-N. Therefore, 88% of the resected tumors were benign spectrum neuroblastic tumors (GN & GNB-I). Seven (7/50, 14%) patients experienced perioperative complication (temporary paralysis, Horner's syndrome, chylothorax, vocal cord paralysis). Recurrence was noted in 1 patient with GN (1/50, 2%) and 3 with GNB-N (3/50, 6%). There were no tumor-related deaths. Patients with GN were older than those with GNB (8.8 years (IQR 6-11.25) vs 5.6 years for GN (IQR 3-7); p = 0.01). GNB tumors were also more likely to have calcifications on imaging (63% vs. 38%, p = .01) and more commonly had MIBG avidity (88% vs 66%, p = .04). There were no significant differences in tumor size or symptoms at presentation. CONCLUSIONS: In children with neuroblastic tumors, older age, CT without tumor calcifications, lack of MIBG avidity, and/or normal urine catecholamines may indicate benign GN. Close observation could be considered for asymptomatic patients meeting these criteria with biopsy-proven GN, with resection reserved for progressive growth or symptom development. However, larger, multicenter studies are needed for further validation. LEVEL OF EVIDENCE: IV.

Thoracoscopic Resection of Thoracic Inlet Neuroblastic Tumors in Young Children.

Background: Thoracic inlet (TI) tumors are rare, and can be particularly challenging to resect due to proximity to mediastinal vessels and nerves. Traditional resection is typically performed through "trapdoor" or sternoclavicular incisions. The purpose of our study was to evaluate the feasibility and effectiveness of thoracoscopic resection of this group of tumors. Methods: We performed a single-center retrospective chart review for children who presented with TI neuroblastic tumors between 2011 and 2020. Demographics, tumor characteristics, treatment, operative complications, and outcomes were collected and analyzed. Results: Eight patients were identified. The median age at diagnosis was 13 months (interquartile range [IQR] 6-32) with median tumor size at diagnosis of 4.1 cm (IQR 3.6-4.4). Neoadjuvant chemotherapy was given in 50% (4/8) with 38% (3/8) undergoing upfront surgery; 1 patient was observed without chemotherapy or surgery. Ultimately, 6 patients had thoracoscopic resection. For thoracoscopic resections, median intraoperative estimated blood loss was 15 mL (IQR 10-28), median operative room time was 199 minutes (IQR 152-259), and median hospital length of stay was 2 days (IQR 2-3). There were two complications: one recurrent laryngeal nerve injury and one new-onset Horner's syndrome. Complete gross total resection was achieved for all children and there were no recurrences or mortalities with a median follow-up of 3 years. Conclusion: Thoracoscopic resection for TI neuroblastic tumors is feasible with minimal morbidity and can lead to adequate oncological resection.

Revised Neuroblastoma Risk Classification System: A Report From the Children's Oncology Group.

PURPOSE: Treatment planning for children with neuroblastoma requires accurate assessment of prognosis. The most recent Children's Oncology Group (COG) risk classification system used tumor stage as defined by the International Neuroblastoma Staging System. Here, we validate a revised classifier using the International Neuroblastoma Risk Group Staging System (INRGSS) and incorporate segmental chromosome aberrations (SCA) as an additional genomic biomarker. METHODS: Newly diagnosed patients enrolled on the COG neuroblastoma biology study ANBL00B1 between 2007 and 2017 with known age, International Neuroblastoma Staging System, and INRGSS stage were identified (N = 4,832). Tumor MYCN status, ploidy, SCA status (1p and 11q), and International Neuroblastoma Pathology Classification histology were determined centrally. Survival analyses were performed for combinations of prognostic factors used in COG risk classification according to the prior version 1, and to validate a revised algorithm (version 2). RESULTS: Most patients with locoregional tumors had excellent outcomes except for those with image-defined risk factors (INRGSS L2) with MYCN amplification (5-year event-free survival and overall survival: 76.3% ± 5.8% and 79.9% ± 5.5%, respectively) or patients age ≥ 18 months with L2 MYCN nonamplified tumors with unfavorable International Neuroblastoma Pathology Classification histology (72.7% ± 5.4% and 82.4% ± 4.6%), which includes the majority of L2 patients with SCA. For patients with stage M (metastatic) and MS (metastatic, special) disease, genomic biomarkers affected risk group assignment for those < 12 months (MYCN) or 12-18 months (MYCN, histology, ploidy, and SCA) of age. In a retrospective analysis of patient outcome, the 5-year event-free survival and overall survival using COG version 1 were low-risk: 89.4% ± 1.1% and 97.9% ± 0.5%; intermediate-risk: 86.1% ± 1.3% and 94.9% ± 0.8%; high-risk: 50.8% ± 1.4% and 61.9% ± 1.3%; and using COG version 2 were low-risk: 90.7% ± 1.1% and 97.9% ± 0.5%; intermediate-risk: 85.1% ± 1.4% and 95.8% ± 0.8%; high-risk: 51.2% ± 1.4% and 62.5% ± 1.3%, respectively. CONCLUSION: A revised 2021 COG neuroblastoma risk classifier (version 2) that uses the INRGSS and incorporates SCAs has been adopted to prospectively define COG clinical trial eligibility and treatment assignment.

Genomic analysis and preclinical xenograft model development identify potential therapeutic targets for MYOD1-mutant soft-tissue sarcoma of childhood.

The myogenic differentiation 1 gene (MYOD1) p.L122R somatic mutation was first discovered in a subset of clinically aggressive embryonal rhabdomyosarcomas and has since been described in both pediatric and adult spindle cell/sclerosing rhabdomyosarcomas. Relatively little is known about the clinical, molecular, and histopathological features of these tumors in children. In order to further characterize the genomic and clinical features of pediatric MYOD1-mutant sarcomas, we evaluated a cohort of soft-tissue sarcoma patients treated at Texas Children's Hospital. Tumor DNA was subjected to next-generation panel sequencing and/or Sanger sequencing of the MYOD1 hotspot mutation. The MYOD1 p.L122R mutation was identified in six tumors, with a variant allele fraction greater than 0.8 in three cases, suggestive of loss of heterozygosity. One sclerosing rhabdomyosarcoma lacking the MYOD1 hotspot mutation was observed to have a MYOD1 copy number gain, also with evidence of loss of heterozygosity. Cancer gene panel sequencing revealed potentially targetable alterations in six of seven (86%) patients with MYOD1 alterations, including four patients with an alteration in the PI3K-AKT pathway: two hotspot PIK3CA mutations and deletions in PTEN and TSC2. On histopathologic review, MYOD1-altered tumors exhibited spindle and/or round cells and varying degrees of hyaline sclerosis. At last follow-up, six patients had died of disease and the seventh progressed early and was subsequently lost to follow-up. Both pre- and post-therapy patient-derived xenograft models were generated from one patient's tumor. These models were confirmed to harbor the MYOD1 and PIK3CA mutations seen in the primary tumor and were shown to be sensitive to PI3K/mTOR inhibition in vitro and in vivo. In conclusion, this study adds to recent reports describing the clinicopathologic and genomic features of MYOD1-altered soft-tissue sarcomas in children, including dismal prognosis and potential molecular targets for therapy. The novel preclinical models developed will facilitate further biological and preclinical study of this rare and aggressive tumor. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Management of Neuroblastoma in Pediatric Patients.

Surgeons caring for patients with neuroblastoma must be familiar with recent developments in assessing risk. In particular, the Children's Oncology Group, along with major international groups, uses the International Neuroblastoma Risk Group Staging System as a risk assessment tool. Accurate risk determination is essential for optimal surgical therapy. Some tumors like neonatal adrenal neuroblastomas and those in the metastatic category can be observed. Very-low-risk and low-risk neuroblastomas can be treated with surgery alone. Intermediate-risk tumors also often require systemic chemotherapy.

Personalized Graduate Medical Education and the Global Surgeon: Training for Resource-Limited Settings.

PROBLEM: The World Health Organization and the World Bank have identified improvement in access to surgical care as an urgent global health challenge and a cost-effective investment in public health. However, trainees in standard U.S. general surgery programs do not have adequate exposure to the procedures, technical skills, and foundational knowledge essential for providing surgical care in resource-limited settings. APPROACH: The Michael E. DeBakey Department of Surgery at Baylor College of Medicine (BCM) created a 7-year global surgery track within its general surgery residency in 2014. Individualized rotations equip residents with the necessary skills, knowledge, and experience to operate in regions with low surgeon density and develop sustainable surgical infrastructures. BCM provides a formal, integrated global surgery curriculum-including 2 years dedicated to global surgery-with surgical specialty rotations in domestic and international settings. Residents tailor their individual experience to the needs of their future clinical practice, region of interest, and surgical specialty. OUTCOMES: There have been 4 major outcomes of the BCM global surgery track: (1) increased exposure for trainees to a broad range of surgeries critical in resource-limited settings, (2) meaningful international partnerships, (3) contributions to global surgery scholarship, and (4) establishment of sustainable global surgery activities. NEXT STEPS: To better facilitate access to safe, timely, and affordable surgical care worldwide, global surgeons should pursue expertise in topics not currently included in U.S. general surgical curricula, such as setting-specific technical skills, capacity building, and organizational collaboration. Future evaluations of the BCM global surgery track will assess the effect of individualized education on trainees' professional identities, clinical practices, academic pursuits, global surgery leadership preparedness, and comfort with technical skills not encompassed in general surgery programs. Increasing availability of quality global surgery training programs would provide a critical next step toward contributing to the delivery of safe surgical care worldwide.

Subcutaneous analgesic system versus epidural for post-operative pain control in surgical pediatric oncology patients.

BACKGROUND/PURPOSE: Pediatric oncology patients often undergo open operations for tumor resection, and epidural catheters are commonly utilized for pain control. Our purpose was to evaluate whether a subcutaneous analgesic system (SAS) provides equivalent post-operative pain control. METHODS: An IRB approved, retrospective chart review of children age <18 undergoing open abdominal, pelvic or thoracic surgery for tumor resection between 2017 and 2019 who received either epidural or SAS for post-operative pain control was performed. Comparisons of morphine milligram equivalents (MME), pain scores, and post-operative course were made using parametric and non-parametric analyses. RESULTS: Of 101 patients, median age was 7 years (2 months-17.9 years). There were 65 epidural and 36 SAS patients. Transverse laparotomy was the most common incision (41%), followed by thoracotomy (29%). Pain scores, MME, urinary catheter days, and post-operative length of stay (LOS) were similar between the two groups. Urinary catheter use was more common in epidural patients (70% vs 30%, p = <0.001). SAS patients had faster time to ambulation and time to regular diet by 1 day (p = 0.02). Epidural patients more commonly had a complication with the pain device (20% vs 3%, p = 0.02) and were more likely to be discharged with narcotics (60% vs. 40%, p = 0.04). Charges associated with the hospital stay were similar between the two groups. CONCLUSION: In pediatric oncology patients undergoing open abdominal, pelvic, and thoracic surgery, SAS may provide similar pain control to epidural, but with faster post-operative recovery, fewer complications, and less discharge narcotic use. A prospective study is needed to validate these results. TYPE OF STUDY: Retrospective Comparative LEVEL OF EVIDENCE: Level III.

Is high-risk neuroblastoma induction chemotherapy possible without G-CSF? A pilot study of safety and treatment delays in the absence of primary prophylactic hematopoietic growth factors.

BACKGROUND/OBJECTIVES: Standard supportive care during induction therapy for high-risk neuroblastoma (HR-NBL) includes primary prophylactic granulocyte colony-stimulating factor (G-CSF) aimed at limiting duration of neutropenia, reducing infection risk, and minimizing treatment delays. Preclinical models suggest that G-CSF promotes maintenance of neuroblastoma cancer stem cells and may reduce the efficacy of chemotherapy. This study's objective was to determine the safety and feasibility of administering induction chemotherapy without routine use of prophylactic G-CSF. DESIGN/METHODS: Children with newly diagnosed HR-NBL received six-cycle induction chemotherapy regimen without prophylactic G-CSF in four cycles. G-CSF was administered for stem cell mobilization after cycle 3 and granulocyte-monocyte colony-stimulating factor after cycle 5 prior to surgical resection of primary disease. The primary outcome measure was the incidence of grade 3 or higher infection. We hypothesized that the per patient infection rate would be comparable to our institutional baseline rate of 58% in patients with HR-NBL receiving induction chemotherapy with prophylactic growth factor support. The trial used an A'Hern single-stage design. RESULTS: Twelve patients with HR-NBL received 58 cycles of chemotherapy on study. Three patients completed the entire six-cycle regimen with no infections. Nine patients experienced grade 3 infections (bacteremia four, urinary tract infection two, skin/soft tissue infection three). No patients experienced grade 4 infections or required intensive care treatment for infection. CONCLUSION: A greater than expected number of serious bacterial infections were observed during administration of induction chemotherapy for HR-NBL without primary prophylactic G-CSF. These results support continued prophylactic administration growth factor during induction chemotherapy.