Eighteen-year survival after GD2-directed Chimeric Antigen Receptor-Modified Immune Effector Cell Treatment for Neuroblastoma.

We report long-term outcomes up to 18 years of a clinical trial treating children with neuroblastoma with EBV-specific T lymphocytes and CD3-activated T cells - each expressing a first-generation chimeric antigen receptor targeting GD2 with barcoded transgenes to allow tracking of each population. Of 11 patients with active disease at infusion, three patients achieved a complete response that was sustained in 2, one for 8 years until lost to follow up and one for 18+ years. Of eight patients with a history of relapse or at high risk of recurrence, five are disease-free at their last follow-up between 10-14 years post-infusion. Intermittent low levels of transgene were detected during the follow up period with significantly greater persistence in those who were long-term survivors. In conclusion, patients with relapsed/refractory neuroblastoma achieved long-term disease control after receiving GD2 CAR-T cell therapy including one patient now in remission of relapsed disease for >18 years.

Strategic infection prevention after genetically modified hematopoietic stem cell therapies: recommendations from the International Society for Cell & Gene Therapy Stem Cell Engineering Committee.

There is lack of guidance for immune monitoring and infection prevention after administration of ex vivo genetically modified hematopoietic stem cell therapies (GMHSCT). We reviewed current infection prevention practices as reported by providers experienced with GMHSCTs across North America and Europe, and assessed potential immunologic compromise associated with the therapeutic process of GMHSCTs described to date. Based on these assessments, and with consensus from members of the International Society for Cell & Gene Therapy (ISCT) Stem Cell Engineering Committee, we propose risk-adapted recommendations for immune monitoring, infection surveillance and prophylaxis, and revaccination after receipt of GMHSCTs. Disease-specific and GMHSCT-specific considerations should guide decision making for each therapy.

Transplantation Referral Patterns for Patients with Newly Diagnosed Higher-Risk Myelodysplastic Syndromes and Acute Myeloid Leukemia at Academic and Community Sites in the Connect® Myeloid Disease Registry: Potential Barriers to Care.

Hematopoietic stem cell transplantation (HCT) is indicated for patients with higher-risk (HR) myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Age, performance status, patient frailty, comorbidities, and nonclinical factors (eg, cost, distance to site) are all recognized as important clinical factors that can influence HCT referral patterns and patient outcomes; however, the proportion of eligible patients referred for HCT in routine clinical practice is largely unknown. This study aimed to assess patterns of consideration for HCT among patients with HR-MDS and AML enrolled in the Connect® Myeloid Disease Registry at community/government (CO/GOV)- or academic (AC)-based sites, as well as to identify factors associated with rates of transplantation referral. We assessed patterns of consideration for and completion of HCT in patients with HR-MDS and AML enrolled between December 12, 2013, and March 6, 2020, in the Connect Myeloid Disease Registry at 164 CO/GOV and AC sites. Registry sites recorded whether patients were considered for transplantation at baseline and at each follow-up visit. The following answers were possible: "considered potentially eligible," "not considered potentially eligible," or "not assessed." Sites also recorded whether patients subsequently underwent HCT at each follow-up visit. Rates of consideration for HCT between CO/GOV and AC sites were compared using multivariable logistic regression analysis with covariates for age and comorbidity. Among the 778 patients with HR-MDS or AML enrolled in the Connect Myeloid Disease Registry, patients at CO/GOV sites were less likely to be considered potentially eligible for HCT than patients at AC sites (27.9% versus 43.9%; P < .0001). Multivariable logistic regression analysis with factors for age (<65 versus ≥65 years) and ACE-27 comorbidity grade (<2 versus ≥2) showed that patients at CO/GOV sites were significantly less likely than those at AC sites to be considered potentially eligible for HCT (odds ratio, 1.6, 95% confidence interval, 1.1 to 2.4; P = .0155). Among patients considered eligible for HCT, 45.1% (65 of 144) of those at CO/GOV sites and 35.7% (41 of 115) of those at AC sites underwent transplantation (P = .12). Approximately one-half of all patients at CO/GOV (50.1%) and AC (45.4%) sites were not considered potentially eligible for HCT; the most common reasons were age at CO/GOV sites (71.5%) and comorbidities at AC sites (52.1%). Across all sites, 17.4% of patients were reported as not assessed (and thus not considered) for HCT by their treating physician (20.7% at CO/GOV sites and 10.7% at AC sites; P = .0005). These findings suggest that many patients with HR-MDS and AML who may be candidates for HCT are not receiving assessment or consideration for transplantation in clinical practice. In addition, treatment at CO/GOV sites and age remain significant barriers to ensuring that all potentially eligible patients are assessed for HCT.

International Society for Cell & Gene Therapy Stem Cell Engineering Committee: Cellular therapies for the treatment of graft-versus-host-disease after hematopoietic stem cell transplant.

BACKGROUND AIMS: Allogeneic hematopoietic stem cell transplant is a curative approach for many malignant and non-malignant hematologic conditions. Despite advances in its prevention and treatment, the morbidity and mortality related to graft-versus-host disease (GVHD) remains. The mechanisms by which currently used pharmacologic agents impair the activation and proliferation of potentially alloreactive T cells reveal pathways essential for the detrimental activities of these cell populations. Importantly, these same pathways can be important in mediating the graft-versus-leukemia effect in recipients transplanted for malignant disease. This knowledge informs potential roles for cellular therapies such as mesenchymal stromal cells and regulatory T cells in preventing or treating GVHD. This article reviews the current state of adoptive cellular therapies focused on GVHD treatment. METHODS: We conducted a search for scientific literature in PubMed® and ongoing clinical trials in clinicaltrial.gov with the keywords "Graft-versus-Host Disease (GVHD)," "Cellular Therapies," "Regulatory T cells (Tregs)," "Mesenchymal Stromal (Stem) Cells (MSCs)," "Natural Killer (NK) Cells," "Myeloid-derived suppressor cells (MDSCs)," and "Regulatory B-Cells (B-regs)." All the published and available clinical studies were included. RESULTS: Although most of the existing clinical data focus on cellular therapies for GVHD prevention, there are observational and interventional clinical studies that explore the potential for cellular therapies to be safe modalities for GVHD treatment while maintaining the graft-versus-leukemia effect in the context of malignant diseases. However, there are multiple challenges that limit the broader use of these approaches in the clinical scenario. CONCLUSIONS: There are many ongoing clinical trials to date with the promise to expand our actual knowledge on the role of cellular therapies for GVHD treatment in an attempt to improve GVHD-related outcomes in the near future.

Analysis of the Role of Plasma 25-Hydroxyvitamin D Levels in Survival Outcomes in Patients from the Phase III MPACT Trial of Metastatic Pancreatic Cancer.

BACKGROUND: We examined overall survival (OS) outcomes based on plasma 25-hydroxyvitamin D [25(OH)D] levels in this post hoc analysis of the phase III MPACT trial of metastatic pancreatic cancer. MATERIALS AND METHODS: Patients were subdivided based on 25(OH)D level: sufficient (≥30 ng/mL), relatively insufficient (20-<30 ng/mL), or insufficient (<20 ng/mL). RESULTS: Of 861 patients randomized in MPACT, 422 were included in this analysis. In the all-patients group, the median OS among those with insufficient, relatively insufficient, and sufficient 25(OH)D levels was 7.9, 9.4, and 7.8 months, respectively. No statistically significant OS difference was observed with relatively insufficient (p = .227) or sufficient (p = .740) versus insufficient 25(OH)D levels or with sufficient vs relatively insufficient (p = .301) 25(OH)D levels. CONCLUSION: No association was observed between plasma 25(OH)D levels and survival. Further investigations are needed to understand any role of vitamin D in pancreatic cancer. Clinical trial identification number. NCT00844649.

Real-world diagnostic testing patterns for assessment of ring sideroblasts and SF3B1 mutations in patients with newly diagnosed lower-risk myelodysplastic syndromes.

INTRODUCTION: The presence of ring sideroblasts (RS) and mutation of the SF3B1 gene are diagnostic of lower-risk (LR) myelodysplastic syndromes (MDS) and are correlated with favorable outcomes. However, information on testing and reporting in community-based clinical settings is scarce. This study from the Connect® MDS/AML Disease Registry aimed to compare the frequency of RS and SF3B1 reporting for patients with LR-MDS, before and after publication of the 2016 World Health Organization (WHO) MDS classification criteria. METHODS: Ring sideroblasts assessment and molecular testing data were collected from patients with LR-MDS at enrollment in the Registry. Patients enrolled between December 2013 and the data cutoff of March 2020 were included in this analysis. RESULTS: Among 489 patients with LR-MDS, 434 (88.8%) underwent RS assessment; 190 were assessed prior to the 2016 WHO guidelines (Cohort A), and 244 after (Cohort B). In Cohort A, 87 (45.8%) patients had RS identified; 29 (33.3%) patients had RS < 15%, none of whom underwent molecular testing for SF3B1. In Cohort B, 96 (39.3%) patients had RS identified; 31 (32.3%) patients had < 15% RS, with 13 undergoing molecular testing of which 10 were assessed for SF3B1. CONCLUSIONS: In the Connect® MDS/AML Registry, only 32% of patients with <15% RS underwent SF3B1 testing after the publication of the WHO 2016 classification criteria. There was no change in RS assessment frequency before and after publication, despite the potential impact on diagnostic subtyping and therapy selection, suggesting an unmet need for education to increase testing rates for SF3B1 mutations.

Open-label, Phase I Study of Nivolumab Combined with nab-Paclitaxel Plus Gemcitabine in Advanced Pancreatic Cancer.

PURPOSE: Assess safety and efficacy of nivolumab plus nab-paclitaxel and gemcitabine in patients with locally advanced/metastatic pancreatic cancer in a two-part, open-label, phase I trial. PATIENTS AND METHODS: Fifty chemotherapy-naive patients received nab-paclitaxel 125 mg/m2 plus gemcitabine 1,000 mg/m2 (days 1, 8, and 15) and nivolumab 3 mg/kg (days 1 and 15) in 28-day cycles. The primary endpoints were dose-limiting toxicities (DLTs; part 1) and grade 3/4 treatment-emergent adverse events (TEAEs) or treatment discontinuation due to TEAEs (parts 1/2). Secondary efficacy endpoints were progression-free survival (PFS), overall survival (OS), and response. Assessment of programmed cell death-ligand 1 (PD-L1) expression was an exploratory endpoint; additional biomarkers were assessed post hoc. RESULTS: One DLT (hepatitis) was reported in part 1 among six DLT-evaluable patients; 48 of 50 patients experienced grade 3/4 TEAEs and 18 discontinued treatment due to TEAEs. One grade 5 TEAE (respiratory failure) was reported. Median [95% confidence interval (CI)] PFS/OS was 5.5 (3.25-7.20 months)/9.9 (6.74-12.16 months) months, respectively [median follow-up for OS, 13.6 months (95% CI, 12.06-23.49 months)]. Overall response rate (95% CI) was 18% (8.6%-31.4%). Median PFS/OS was 5.5/9.7 months (PD-L1 <5%) and 6.8/11.6 months (PD-L1 ≥5%), respectively. Proportion of peripheral Ki67+ CD8+/CD4+ cells increased significantly from baseline to cycle 3; median peak on-treatment Ki67+ CD8+ T-cell values were higher in responders than in nonresponders. CONCLUSIONS: The safety profile of nivolumab plus nab-paclitaxel and gemcitabine at standard doses in advanced pancreatic cancer was manageable, with no unexpected safety signals. Overall, the clinical results of this study do not support further investigation.

Nomogram for Estimating Overall Survival in Patients With Metastatic Pancreatic Cancer.

OBJECTIVES: This analysis investigated nomogram use to evaluate metastatic pancreatic cancer prognosis. METHODS: Thirty-four baseline factors were examined in the Metastatic Pancreatic Adenocarcinoma Clinical Trial (MPACT) (nab-paclitaxel plus gemcitabine vs gemcitabine) data set. Factors significantly (P < 0.1) associated with overall survival (OS) in a univariable model or with known clinical relevance were tested further. In a multivariable model, factors associated with OS (P < 0.1) were selected to generate the primary nomogram, which was internally validated using bootstrapping, a concordance index, and calibration plots. RESULTS: Using data from 861 patients, 6 factors were retained (multivariable analysis): neutrophil-lymphocyte ratio, albumin level, Karnofsky performance status, sum of longest diameter of target lesions, presence of liver metastases, and previous Whipple procedure. The nomogram distinguished low-, medium-, and high-risk groups (concordance index, 0.67; 95% confidence interval, 0.65-0.69; median OS, 11.7, 8.0, and 3.3 months, respectively). CONCLUSIONS: This nomogram may guide estimates of the range of OS outcomes and contribute to patient stratification in future prospective metastatic pancreatic cancer trials; however, external validation is required to improve estimate reliability and applicability to a general patient population. Caution should be exercised in interpreting these results for treatment decisions: patient characteristics could differ from those included in the nomogram development.

Diagnostic and molecular testing patterns in patients with newly diagnosed acute myeloid leukemia in the Connect® MDS/AML Disease Registry.

Diagnostic and molecular genetic testing are key in advancing the treatment of acute myeloid leukemia (AML), yet little is known about testing patterns outside of clinical trials, especially in older patients. We analyzed diagnostic and molecular testing patterns over time in 565 patients aged ≥ 55 years with newly diagnosed AML enrolled in the Connect® MDS/AML Disease Registry (NCT01688011) in the United States. Diagnostic data were recorded at enrolment and compared with published guidelines. The percentage of bone marrow blasts was reported for 82.1% of patients, and cellularity was the most commonly reported bone marrow morphological feature. Flow cytometry, karyotyping, molecular testing, and fluorescence in situ hybridization were performed in 98.8%, 95.4%, 75.9%, and 75.7% of patients, respectively. Molecular testing was done more frequently at academic than community/government sites (84.3% vs 70.2%; P < .001). Enrolment to the Registry after 2016 was significantly associated with molecular testing at academic sites (odds ratio [OR] 2.59; P = .023) and at community/government sites (OR 4.85; P < .001) in logistic regression analyses. Better understanding of practice patterns may identify unmet needs and inform institutional protocols regarding the diagnosis of patients with AML.

Safety and Efficacy Results of a Phase I, Open-Label Study of Concurrent and Delayed Nivolumab in Combination With nab-Paclitaxel and Carboplatin in Advanced Non-small Cell Lung Cancer.

Introduction: Multicenter, phase I study of concurrent and delayed nivolumab plus nab-paclitaxel/carboplatin in advanced non-small cell lung cancer (NSCLC). Methods: Chemotherapy-naive patients with advanced NSCLC (ineligible for potentially curative radiation or surgery) received nab-paclitaxel 100 mg/m2 (days 1, 8, 15) and carboplatin area under the curve 6 (day 1) intravenously every 21 days (first 4 cycles); nivolumab 5 mg/kg was administered intravenously (day 15) beginning in cycle 1 (concurrent) or cycle 3 (delayed) in separate cohorts and continued beyond the 4 chemotherapy cycles. The primary objective was to assess safety. Secondary objectives were to assess tolerability and explore antitumor activity. Results: All 32 patients received chemotherapy; 20 of 22 and 6 of 10 patients also received concurrent or delayed nivolumab, respectively. No dose-limiting toxicities were reported in the concurrent cohort; 1 dose-limiting toxicity was reported in the delayed cohort. In the concurrent cohort, 20 patients (91%) had ≥1 grade 3/4 treatment-emergent adverse event (TEAE), and 7 (32%) discontinued treatment due to TEAEs. In the delayed cohort, all patients had ≥1 grade 3/4 TEAE, and 2 (20%) discontinued due to TEAEs. The median progression-free and overall survival, respectively, were 10.5 and 29.3 months in the concurrent cohort and 4.1 and 8.2 months in the delayed cohort. Conclusions: The safety profile of the combination was consistent with that of individual agents and generally similar in the 2 cohorts. Efficacy outcomes in the concurrent cohort, but not in the delayed cohort, were encouraging and support the rationale for concurrent administration of nivolumab with nab-paclitaxel/carboplatin for the treatment of advanced NSCLC. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02309177.

Dual targeting of IGF-1R and ErbB3 as a potential therapeutic regimen for ovarian cancer.

Therapeutically targeting receptor tyrosine kinases has proven to be paramount to overcoming chemotherapy resistance in several cancer indications, improving patient outcomes. Insulin-Like Growth Factor Receptor 1 (IGF-1R) and Epidermal Growth Factor Receptor 3 (ErbB3) have been implicated as two such drivers of resistance, however their simultaneous role in ovarian cancer chemotherapy resistance remains poorly elucidated. The aim of this work is to determine the effects of dual IGF-1R/ErbB3 inhibition on ovarian cancer cell signaling, growth, and in vivo efficacy. Assessment of in vitro chemotherapy response across a panel of ovarian cancer cell lines revealed that increased IGF-1R cell surface expression correlates with decreased sensitivity to chemotherapy, and that growth induced by IGF-1R and ErbB3 ligands is blocked by the tetravalent bispecific antibody targeting IGF-1R and ErbB3, istiratumab. In vitro chemotherapy treatment increased ovarian cancer cell line capacity to activate prosurvival PI3K signaling in response to ligand, which could be prevented with istiratumab treatment. Furthermore, in vivo efficacy of standard of care chemotherapies using a xenograft model of ovarian cancer was potentiated with istiratumab. Our results suggest a role for IGF-1R and ErbB3 in driving chemotherapy resistance of ovarian cancer.

A Phase I/II Open-Label Multicenter Single-Arm Study of FABLOx (Metronomic 5-Fluorouracil Plus nab-Paclitaxel, Bevacizumab, Leucovorin, and Oxaliplatin) in Patients with Metastatic Pancreatic Cancer.

Purpose: To evaluate safety and preliminary efficacy of metronomic 5-fluorouracil plus nab-paclitaxel, bevacizumab, leucovorin, and oxaliplatin (FABLOx) in patients with newly diagnosed metastatic pancreatic cancer (MPC). Methods: A total of 12 treatment-naive patients (aged 18-65 years, Eastern Cooperative Oncology Group performance status [ECOG PS] ≤1) with MPC received 5-fluorouracil 180 mg/m2 per day (days 1-14 continuous infusion); nab-paclitaxel 75 mg/m2, leucovorin 20 mg/m2, and oxaliplatin 40 mg/m2 (days 1, 8, and 15); and bevacizumab 5 mg/kg (days 1 and 15) administered intravenously in each 28-day cycle. The primary end-point was incidence of dose-limiting toxicities (DLTs) in cycle 1. Safety was further evaluated as a secondary end-point; preliminary efficacy was also examined. Results: Two DLTs (grade 3 anemia requiring transfusion and grade 3 mucositis unresponsive to treatment within 4 days of onset) were observed in one of six patients enrolled in dose cohort 1. Cohort 1 was expanded from 6 to 12 patients to further evaluate safety, per the investigators' recommendation. All patients discontinued treatment. The most common grade ≥3 adverse events were abdominal pain, fatigue, mucositis, and decreased neutrophil count. Objective response rate was 33% (four partial responses). Median progression-free survival (PFS) and overall survival (OS) were 5.6 (95% confidence interval [CI], 1.7-11.3) and 9.9 (95% CI, 4.4-13.2) months, respectively; 1-year PFS and OS rates were 12.2% (95% CI, 0.7-40.8) and 38.9% (95% CI, 12.6-65.0). Conclusion: FABLOx is feasible and tolerable in patients newly diagnosed with MPC. However, preliminary efficacy data are inconclusive for continued investigation in a phase II trial.

Epstein-Barr Virus (EBV)-derived BARF1 encodes CD4- and CD8-restricted epitopes as targets for T-cell immunotherapy.

BACKGROUND AIMS: EBV type II latency tumors, such as Hodgkin lymphoma (HL), Non-Hodgkin lymphoma (NHL) and nasopharyngeal carcinoma, express a limited array of EBV antigens including Epstein-Barr nuclear antigen (EBNA)1, latent membrane protein (LMP)1, LMP2, and BamH1-A right frame 1 (BARF1). Adoptive immunotherapy for these malignancies have focused on EBNA1, LMP1 and LMP2 because little is known about the cellular immune response to BARF1. METHODS: To investigate whether BARF1 is a potential T-cell immunotherapy target, we determined the frequency of BARF1-specific T-cell responses in the peripheral blood of EBV-seropositive healthy donor and patients with EBV-positive malignancies, mapped epitopes and evaluated the effector function of ex vivo-generated BARF1-specific T-cell lines. RESULTS: BARF1-specific T cells were present in the peripheral blood of 12/16 (75%) EBV-positive healthy donors and 13/20 (65%) patients with EBV-positive malignancies. Ex vivo expanded BARF1-specific T-cell lines contained CD4- and CD8-positive T-cell subpopulations, and we identified 23 BARF1 peptides, which encoded major histocompatibility complex class I- and/or II-restricted epitopes. Epitope mapping identified one human leukocyte antigen (HLA)-A*02-restricted epitope that was recognized by 50% of HLA-A*02, EBV-seropositive donors and one HLA-B*15(62)-restricted epitope. Exvivo expanded BARF1-specific T cells recognized and killed autologous, EBV-transformed lymphoblastoid cell lines and partially HLA-matched EBV-positive lymphoma cell lines. DISCUSSION: BARF1 should be considered as an immunotherapy target for EBV type II (and III) latency. Targeting BARF1, in addition to EBNA1, LMP1 and LMP2, has the potential to improve the efficacy of current T-cell immunotherapy approaches for these malignancies.

Dual Inhibition of IGF-1R and ErbB3 Enhances the Activity of Gemcitabine and Nab-Paclitaxel in Preclinical Models of Pancreatic Cancer.

Purpose: Insulin-like growth factor receptor 1 (IGF-1R) is critically involved in pancreatic cancer pathophysiology, promoting cancer cell survival and therapeutic resistance. Assessment of IGF-1R inhibitors in combination with standard-of-care chemotherapy, however, failed to demonstrate significant clinical benefit. The aim of this work is to unravel mechanisms of resistance to IGF-1R inhibition in pancreatic cancer and develop novel strategies to improve the activity of standard-of-care therapies.Experimental Design: Growth factor screening in pancreatic cancer cell lines was performed to identify activators of prosurvival PI3K/AKT signaling. The prevalence of activating growth factors and their receptors was assessed in pancreatic cancer patient samples. Effects of a bispecific IGF-1R and ErbB3 targeting antibody on receptor expression, signaling, cancer cell viability and apoptosis, spheroid growth, and in vivo chemotherapy activity in pancreatic cancer xenograft models were determined.Results: Growth factor screening in pancreatic cancer cells revealed insulin-like growth factor 1 (IGF-1) and heregulin (HRG) as the most potent AKT activators. Both growth factors reduced pancreatic cancer cell sensitivity to gemcitabine or paclitaxel in spheroid growth assays. Istiratumab (MM-141), a novel bispecific antibody that blocks IGF-1R and ErbB3, restored the activity of paclitaxel and gemcitabine in the presence of IGF-1 and HRG in vitro Dual IGF-1R/ErbB3 blocking enhanced chemosensitivity through inhibition of AKT phosphorylation and promotion of IGF-1R and ErbB3 degradation. Addition of istiratumab to gemcitabine and nab-paclitaxel improved chemotherapy activity in vivoConclusions: Our findings suggest a critical role for the HRG/ErbB3 axis and support the clinical exploration of dual IGF-1R/ErbB3 blocking in pancreatic cancer. Clin Cancer Res; 24(12); 2873-85. ©2018 AACR.

CAR T Cells Administered in Combination with Lymphodepletion and PD-1 Inhibition to Patients with Neuroblastoma.

Targeting disialoganglioside (GD2) on neuroblastoma (NB) with T cells expressing a first-generation chimeric antigen receptor (CAR) was safe, but the cells had poor expansion and long-term persistence. We developed a third-generation GD2-CAR (GD2-CAR3) and hypothesized that GD2-CAR3 T cells (CARTs) would be safe and effective. This phase 1 study enrolled relapsed or refractory NB patients in three cohorts. Cohort 1 received CART alone, cohort 2 received CARTs plus cyclophosphamide and fludarabine (Cy/Flu), and cohort 3 was treated with CARTs, Cy/Flu, and a programmed death-1 (PD-1) inhibitor. Eleven patients were treated with CARTs. The infusions were safe, and no dose-limiting toxicities occurred. CARTs were detectable in cohort 1, but the lymphodepletion induced by Cy/Flu increased circulating levels of the homeostatic cytokine interleukin (IL)-15 (p = 0.003) and increased CART expansion by up to 3 logs (p = 0.03). PD-1 inhibition did not further enhance expansion or persistence. Antitumor responses at 6 weeks were modest. We observed a striking expansion of CD45/CD33/CD11b/CD163+ myeloid cells (change from baseline, p = 0.0126) in all patients, which may have contributed to the modest early antitumor responses; the effect of these cells merits further study. Thus, CARTs are safe, and Cy/Flu can further increase their expansion.

The optimal timing of surgical resection in high-risk neuroblastoma.

BACKGROUND: While most high-risk neuroblastoma (HRNB) patients are enrolled in cooperative group or institutional protocols, variability exists within these protocols as to when surgical resection of the primary tumor should be performed after neoadjuvant induction chemotherapy. We sought to determine if the number of chemotherapy cycles prior to surgery affects surgical or survival outcomes in HRNB patients. METHODS: We performed a retrospective review of all HRNB patients <18years of age from 2000 to 2010, at Texas Children's Hospital. Patients were stratified based on the number of neoadjuvant induction chemotherapy cycles prior to surgical resection. Pre and post- chemotherapy tumor size, MYCN status, iodine-131-metaiodobenzylguanidine (MIBG) score at diagnosis, extent of surgical resection, estimated surgical blood loss, post-operative outcomes, and event free (EFS) and overall survival (OS) were evaluated. Data were analyzed using Wilcoxon rank-sum test, Kruskal-Wallis test, Fisher's exact test, Kaplan-Meier analyses, and Cox regression analyses. P-value <0.05 was considered significant. RESULTS: Data from 50 patients with HRNB were analyzed. Patients were stratified by the number of cycles of chemotherapy received prior to surgery. Six patients received 2cycles of chemotherapy (12%), 20 patients received 3cycles (40%), 13 patients received 4cycles (26%), and 11 patients received 5cycles (22%) prior to surgical resection of the primary tumor. The 5-year OS was 33%, 45%, 83% and 36% in patients who received 2, 3, 4 and 5cycles of chemotherapy prior to surgery, respectively (p=0.07). Multivariate analysis revealed that patients who received 4cycles of chemotherapy had a significantly lower mortality (HR: 0.11, 95% CI: 0.01-0.87, p=0.04) compared to those with 2cycles of chemotherapy. Among the different cohorts, there were no differences with respect to MYCN status, MIBG score at diagnosis, incidence of bone marrow metastasis, extent of surgical resection, estimated blood loss, incidence of post-operative complications, or length of stay. CONCLUSION: HRNB patients who receive 4cycles of chemotherapy prior to surgical resection have a superior OS than patients who receive 2. Based on the superior survival of patients who received 4cycles of chemotherapy prior to surgery, further studies are warranted to elucidate these differences.

Cellular immunotherapy for pediatric solid tumors.

Substantial progress has been made in the treatment of pediatric solid tumors over the past 4 decades. However, children with metastatic and or recurrent disease continue to do poorly despite the aggressive multi-modality conventional therapies. The increasing understanding of the tumor biology and the interaction between the tumor and the immune system over the recent years have led to the development of novel immune-based therapies as alternative options for some of these high-risk malignancies. The safety and anti-tumor efficacy of various tumor vaccines and tumor-antigen specific immune cells are currently being investigated for various solid tumors. In early clinical trials, most of these cellular therapies have been well tolerated and have shown promising clinical responses. Although substantial work is being done in this field, the available knowledge for pediatric tumors remains limited. We review the contemporary early phase cell-based immunotherapy efforts for pediatric solid tumors and discuss the rationale and the challenges thereof.

Neuroblastoma: molecular pathogenesis and therapy.

Neuroblastoma is a developmental tumor of young children arising from the embryonic sympathoadrenal lineage of the neural crest. Neuroblastoma is the primary cause of death from pediatric cancer for children between the ages of one and five years and accounts for ∼13% of all pediatric cancer mortality. Its clinical impact and unique biology have made this aggressive malignancy the focus of a large concerted translational research effort. New insights into tumor biology are driving the development of new classification schemas. Novel targeted therapeutic approaches include small-molecule inhibitors as well as epigenetic, noncoding-RNA, and cell-based immunologic therapies. In this review, recent insights regarding the pathogenesis and biology of neuroblastoma are placed in context with the current understanding of tumor biology and tumor/host interactions. Systematic classification of patients coupled with therapeutic advances point to a future of improved clinical outcomes for this biologically distinct and highly aggressive pediatric malignancy.