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Dive into the research topics where Richard Sposto is active.

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Featured researches published by Richard Sposto.


Journal of Clinical Oncology | 2006

Phase III Study of Craniospinal Radiation Therapy Followed by Adjuvant Chemotherapy for Newly Diagnosed Average-Risk Medulloblastoma

Roger J. Packer; Amar Gajjar; Gilbert Vezina; Lucy B. Rorke-Adams; Peter C. Burger; Patricia L. Robertson; Lisa Bayer; Deborah Lafond; Bernadine Donahue; Maryanne H. Marymont; Karin M. Muraszko; James Langston; Richard Sposto

PURPOSE To determine the event-free survival (EFS) and overall survival of children with average-risk medulloblastoma and treated with reduced-dose craniospinal radiotherapy (CSRT) and one of two postradiotherapy chemotherapies. METHODS Four hundred twenty-one patients between 3 years and 21 years of age with nondisseminated medulloblastoma (MB) were prospectively randomly assigned to treatment with 23.4 Gy of CSRT, 55.8 Gy of posterior fossa RT, plus one of two adjuvant chemotherapy regimens: lomustine (CCNU), cisplatin, and vincristine; or cyclophosphamide, cisplatin, and vincristine. Results Forty-two of 421 patients enrolled were excluded from analysis. Sixty-six of the remaining 379 patients had incompletely assessable postoperative studies. Five-year EFS and survival for the cohort of 379 patients was 81% +/- 2.1% and 86% +/- 9%, respectively (median follow-up over 5 years). EFS was unaffected by sex, race, age, treatment regimen, brainstem involvement, or excessive anaplasia. EFS was detrimentally affected by neuroradiographic unassessability. Patients with areas of frank dissemination had a 5-year EFS of 36% +/- 15%. Sixty-seven percent of progressions had some component of dissemination. There were seven second malignancies. Infections occurred more frequently on the cyclophosphamide arm and electrolyte abnormalities were more common on the CCNU regimen. CONCLUSION This study discloses an encouraging EFS rate for children with nondisseminated MB treated with reduced-dose craniospinal radiation and chemotherapy. Additional, careful, step-wise reductions in CSRT in adequately staged patients may be possible.


Nature Genetics | 2013

The genetic landscape of high-risk neuroblastoma

Trevor J. Pugh; Olena Morozova; Edward F. Attiyeh; Shahab Asgharzadeh; Jun S. Wei; Daniel Auclair; Scott L. Carter; Kristian Cibulskis; Megan Hanna; Adam Kiezun; Jaegil Kim; Michael S. Lawrence; Lee Lichenstein; Aaron McKenna; Chandra Sekhar Pedamallu; Alex H. Ramos; Erica Shefler; Andrey Sivachenko; Carrie Sougnez; Chip Stewart; Adrian Ally; Inanc Birol; Readman Chiu; Richard Corbett; Martin Hirst; Shaun D. Jackman; Baljit Kamoh; Alireza Hadj Khodabakshi; Martin Krzywinski; Allan Lo

Neuroblastoma is a malignancy of the developing sympathetic nervous system that often presents with widespread metastatic disease, resulting in survival rates of less than 50%. To determine the spectrum of somatic mutation in high-risk neuroblastoma, we studied 240 affected individuals (cases) using a combination of whole-exome, genome and transcriptome sequencing as part of the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. Here we report a low median exonic mutation frequency of 0.60 per Mb (0.48 nonsilent) and notably few recurrently mutated genes in these tumors. Genes with significant somatic mutation frequencies included ALK (9.2% of cases), PTPN11 (2.9%), ATRX (2.5%, and an additional 7.1% had focal deletions), MYCN (1.7%, causing a recurrent p.Pro44Leu alteration) and NRAS (0.83%). Rare, potentially pathogenic germline variants were significantly enriched in ALK, CHEK2, PINK1 and BARD1. The relative paucity of recurrent somatic mutations in neuroblastoma challenges current therapeutic strategies that rely on frequently altered oncogenic drivers.


Journal of Clinical Oncology | 2005

Multiagent Chemotherapy and Deferred Radiotherapy in Infants With Malignant Brain Tumors: A Report From the Children’s Cancer Group

J. Russell Geyer; Richard Sposto; Mark Jennings; James M. Boyett; Richard A. Axtell; David Breiger; Emmett Broxson; Bernadine Donahue; Jonathan L. Finlay; Joel W. Goldwein; Linda Heier; Dennis L. Johnson; Claire Mazewski; Douglas C. Miller; Roger J. Packer; Diane Puccetti; Jerilynn Radcliffe; May Lin Tao; Tania Shiminski-Maher

PURPOSE To evaluate response rate, event-free survival (EFS), and toxicity of two chemotherapeutic regimens for treatment of children younger than 36 months with malignant brain tumors and to estimate control intervals without irradiation in children with no residual tumor after initial surgery and induction chemotherapy and with delayed irradiation in patients with residual tumor or metastatic disease at diagnosis. PATIENTS AND METHODS Patients were randomly assigned to one of two regimens of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide v vincristine, carboplatin, ifosfamide, and etoposide). Maintenance chemotherapy began after induction in children without progressive disease. Children with no residual tumors after induction therapy and no metastatic disease at diagnosis were not to receive radiation therapy unless their tumors progressed. RESULTS Two hundred ninety-nine infants were enrolled. Forty-two percent of patients responded to induction chemotherapy. At 5 years from study entry, the EFS rate was 27% +/- 3%, and the survival rate was 43% +/- 3%. There was no significant difference between the two arms in terms of response rate or EFS. For medulloblastoma, supratentorial primitive neuroectodermal tumor, ependymoma, and rhabdoid tumors, 5-year EFS rates were 32% +/- 5%, 17% +/- 6%, and 32% +/- 6%, and 14% +/- 7%, respectively. Fifty-eight percent of patients who were alive 5 years after study entry had not received radiation therapy. CONCLUSION Intensified induction chemotherapy resulted in a high response rate of malignant brain tumors in infants. Survival was comparable to that of previous studies, and most patients who survived did not receive radiation therapy.


Journal of Clinical Investigation | 2009

Vα24-invariant NKT cells mediate antitumor activity via killing of tumor-associated macrophages

Liping Song; Shahab Asgharzadeh; Jill Salo; Kelly Engell; Hong-Wei Wu; Richard Sposto; Tasnim Ara; Ayaka M. Silverman; Yves A. DeClerck; Robert C. Seeger; Leonid S. Metelitsa

Tumor infiltration with Valpha24-invariant NKT cells (NKTs) associates with favorable outcome in neuroblastoma and other cancers. Although NKTs can be directly cytotoxic against CD1d+ cells, the majority of human tumors are CD1d-. Therefore, the role of NKTs in cancer remains largely unknown. Here, we demonstrate that CD68+ tumor-associated monocytes/macrophages (TAMs) represented the majority of CD1d-expressing cells in primary human neuroblastomas. TAMs stimulated neuroblastoma growth in human cell lines and their xenografts in NOD/SCID mice via IL-6 production. Indeed, TAMs produced IL-6 in primary tumors and in the BM of patients with metastatic neuroblastoma. Gene expression analysis using TaqMan low-density arrays of 129 primary human neuroblastomas without MYCN amplification revealed that high-level expression of TAM-specific genes (CD14, CD16, IL6, IL6R, and TGFB1) was associated with poor 5-year event-free survival. While NKTs were not cytotoxic against neuroblastoma cells, they effectively killed monocytes pulsed with tumor cell lysate. The killing of monocytes was CD1d restricted because it was inhibited by a CD1d-specific mAb. Cotransfer of human monocytes and NKTs to tumor-bearing NOD/SCID mice decreased monocyte number at the tumor site and suppressed tumor growth compared with mice transferred with monocytes alone. Thus, killing of TAMs reveals what we believe to be a novel mechanism of NKT antitumor activity that relates to the disease outcome.


Journal of Clinical Oncology | 2012

Randomized Study of Two Chemotherapy Regimens for Treatment of Low-Grade Glioma in Young Children: A Report From the Children's Oncology Group

Joann L. Ater; Tianni Zhou; Emiko J. Holmes; Claire Mazewski; Timothy N. Booth; David R. Freyer; Ken Lazarus; Roger J. Packer; Michael D. Prados; Richard Sposto; Gilbert Vezina; Jeffrey H. Wisoff; Ian F. Pollack

PURPOSE Surgery is curative therapy for pediatric low-grade gliomas (LGGs) in areas of the brain amenable to complete resection. However, LGGs located in areas where complete resection is not possible can threaten both function and life. The purpose of this study was to compare two chemotherapy regimens for LGGs in children younger than age 10 years for whom radiotherapy was felt by the practitioner to pose a high risk of neurodevelopmental injury. PATIENTS AND METHODS Previously untreated children younger than age 10 years with progressive or residual LGGs were eligible. Children were randomly assigned to receive carboplatin and vincristine (CV) or thioguanine, procarbazine, lomustine, and vincristine (TPCV). Children with neurofibromatosis are reported separately. Results Of 274 randomly assigned patients who met eligibility requirements, 137 received CV and 137 received TPCV. The 5-year event-free survival (EFS) and overall survival (OS) rates for all eligible patients were 45% ± 3.2% and 86% ± 2.2%, respectively. The 5-year EFS rates were 39% ± 4% for CV and 52% ± 5% for TPCV (stratified log-rank test P = .10; cure model analysis P = .007). On multivariate analysis, factors independently predictive of worse EFS and OS were younger age and tumor size greater than 3 cm(2). Tumor location in the thalamus was also associated with poor OS. CONCLUSION The difference in EFS between the regimens did not reach significance on the basis of the stratified log-rank test. The 5-year EFS was higher for TPCV on the basis of the cure model analysis. Differences in toxicity may influence physician choice of regimens.


Journal of Clinical Oncology | 1999

Treatment Outcome and Prognostic Factors for Infants With Acute Lymphoblastic Leukemia Treated on Two Consecutive Trials of the Children's Cancer Group

Gregory H. Reaman; Richard Sposto; Martha G. Sensel; Beverly J. Lange; James H. Feusner; Nyla A. Heerema; Marcia Leonard; Emiko J. Holmes; Harland N. Sather; Thomas W. Pendergrass; Helen S. Johnstone; R T O'Brien; Peter G. Steinherz; Paul S. Gaynon; Michael E. Trigg; Fatih M. Uckun

PURPOSE Infants represent a very poor risk group for acute lymphoblastic leukemia (ALL). We report treatment outcome for such patients treated with intensive therapy on consecutive Childrens Cancer Group (CCG) protocols. PATIENTS AND METHODS Between 1984 and 1993, infants with newly diagnosed ALL were enrolled onto CCG-107 (n = 99) and CCG-1883 (n = 135) protocols. Postconsolidation therapy was more intensive on CCG-1883. On both studies, prophylactic treatment of the CNS included both high-dose systemic chemotherapy and intrathecal therapy, in contrast to whole-brain radiotherapy, which was used in earlier studies. RESULTS Most patients (>95%) achieved remission with induction therapy. The most frequent event was a marrow relapse (46 patients on CCG-107 and 66 patients on CCG- 1883). Four-year event-free survival was 33% (SE = 4.7%) on CCG-107 and 39% (SE = 4.2%) on CCG- 1883. Both studies represent an improvement compared with a 22% (SE = 5.1%) event-free survival for historical controls. Four-year cumulative probabilities of any marrow relapse or an isolated CNS relapse were, respectively, 49% (SE = 5%) and 9% (SE = 3%) on CCG-107 and 50% (SE = 5%) and 3% (SE = 2%) on CCG-1883, compared with 63% (SE = 6%) and 5% (SE = 3%) for the historical controls. Independent adverse prognostic factors were age less than 3 months, WBC count of more than 50,000/microL, CD10 negativity, slow response to induction therapy, and presence of the translocation t(4;11). CONCLUSION Outcome for infants on CCG-107 and CCG- 1883 improved, compared with historical controls. Marrow relapse remains the primary mode of failure. Isolated CNS relapse rates are low, indicating that intrathecal chemotherapy combined with very-high-dose systemic therapy provides adequate protection of the CNS. The overall unsatisfactory outcome observed for the infant ALL population warrants the future use of novel alternative therapies.


British Journal of Haematology | 2003

Burkitt's and Burkitt‐like lymphoma in children and adolescents: a review of the Children's Cancer Group Experience

Mitchell S. Cairo; Richard Sposto; Sherrie L. Perkins; Anna T. Meadows; Margo L. Hoover-Regan; James R. Anderson; Stuart E. Siegel; Mark A. Lones; Nicole Tedeschi-Blok; Marshall E. Kadin; Carl R. Kjeldsberg; John F. Wilson; Warren G. Sanger; Erin Morris; Mark Krailo; Jonathan L. Finlay

Summary. Historically, the survival of children and adolescents with Burkitts and Burkitt‐like lymphoma had been poor. Recently, short and intensive chemotherapy appears to have improved disease outcome. We therefore reviewed the results of four successive Childrens Cancer Group trials conducted on 470 children with disseminated Burkitts and Burkitt‐like lymphoma. Of the patients studied, the median age was 8 years (0–21 years), the male:female ratio was 4:1, 58% had lactate dehydrogenase (LDH) ≥ 500 IU/l, 23% had M2 or M3 bone marrow (BM), and 12% demonstrated central nervous system involvement. In a multivariate analysis, the 4‐year event‐free survival (EFS) in patients ≥ 15‐years‐old compared with < 15‐year‐old was 34 ± 7 versus 59 ± 2% (P < 0·05), the 4‐year EFS of M2/M3 compared with M1 BM was 38 ± 5 versus 63 ± 3% (P < 0·001), and the 4‐year EFS with LDH ≥ 500 IU/l compared with LDH < 500 IU/l was 49 ± 3 versus 71 ± 4% (P < 0·001). Furthermore, patients treated on the most recent protocol, which was short and more intensive, had a significantly improved survival compared with those on previous trials (4‐year EFS 80 ± 6 versus 54 ± 2%, P < 0·001). In summary, the outcome for childhood Burkitts and Burkitt‐like lymphoma has recently improved with the use of short and intensive B‐cell non‐Hodgkins lymphoma‐directed therapy.


Journal of Clinical Oncology | 1993

Long-term follow-up of patients treated with COMP or LSA2L2 therapy for childhood non-Hodgkin's lymphoma: a report of CCG-551 from the Childrens Cancer Group

James R. Anderson; R D Jenkin; John F. Wilson; Carl R. Kjeldsberg; Richard Sposto; R R Chilcote; Peter F. Coccia; P R Exelby; Stuart E. Siegel; Anna T. Meadows

PURPOSE We analyzed the long-term results of a Childrens Cancer Group (CCG) randomized study comparing cyclophosphamide, vincristine, methotrexate, and prednisone (COMP) versus LSA2L2 as treatment for childhood non-Hodgkins lymphoma. The initial results were previously reported (N Engl J Med 308:559, 1983). PATIENTS AND METHODS A total of 429 patients are reported here, 68 with localized disease and 361 with disseminated disease. The distribution of disseminated-disease patients by histologic type was 164 lymphoblastic, 60 large-cell, and 137 undifferentiated lymphomas. Median follow-up duration of surviving patients is 8 years. RESULTS Event-free survival (EFS) of patients with localized disease was 84% at 5 years. No differences were seen between the two treatment regimens. Results for patients with disseminated disease was dependent on histologic subtype: patients with lymphoblastic lymphoma did better when treated with LSA2L2 (5-year EFS of 64% v 35% for COMP); COMP produced better results for patients with undifferentiated lymphoma (5-year EFS of 50% v 29% for LSA2L2). Results for large-cell lymphoma patients were similar (5-year EFS of 52% for COMP v 43% for LSA2L2). Five percent of patients died of treatment-related complications while on therapy (primarily infections). Only four deaths without progression have been observed off-therapy (two from restrictive lung disease, one from an acute asthma attack, one from colon cancer). Patient survival rates after recurrence were poor. CONCLUSION Treatment success can be expected in 84% of pediatric patients with localized non-Hodgkins lymphoma. For patients with disseminated disease, treatment success can be expected in 64% of those with lymphoblastic and 50% of those with undifferentiated or large-cell disease. To date, late adverse events are rare.


Journal of Clinical Oncology | 2010

Outcome of Patients Treated for Relapsed or Refractory Acute Lymphoblastic Leukemia: A Therapeutic Advances in Childhood Leukemia Consortium Study

Richard H. Ko; Lingyun Ji; Phillip Barnette; Bruce Bostrom; Raymond J. Hutchinson; Elizabeth A. Raetz; Nita L. Seibel; Clare J. Twist; Elena Eckroth; Richard Sposto; Paul S. Gaynon; Mignon L. Loh

PURPOSE Despite improvements in treatment, approximately 20% of patients with acute lymphoblastic leukemia (ALL) experience relapse and do poorly. The Therapeutic Advances in Childhood Leukemia (TACL) Consortium was assembled to assess novel drugs for children with resistant leukemia. We hypothesize that novel agents and combinations that fail to improve baseline complete remission rates in comparable populations are unlikely to contribute to better outcomes and should be abandoned. We sought to define response rates and disease-free survival (DFS) rates in patients treated at TACL institutions, which could serve as a comparator for future studies. PATIENTS AND METHODS We performed a retrospective cohort review of patients with relapsed and refractory ALL previously treated at TACL institutions between the years of 1995 and 2004. Data regarding initial and relapsed disease characteristics, disease response, and survival were collected and compared with those of published reports. RESULTS Complete remission (CR) rates (mean +/- SE) were 83% +/- 4% for early first marrow relapse, 93% +/- 3% for late first marrow relapse, 44% +/- 5% for second marrow relapse, and 27% +/- 6% for third marrow relapse. Five-year DFS rates in CR2 and CR3 were 27% +/- 4% and 15% +/- 7% respectively. CONCLUSION We generally confirm a 40% CR rate for second and subsequent relapse, but our remission rate for early first relapse seems better than that reported in the literature (83% v approximately 70%). Our data may allow useful modeling of an expected remission rate for any population of patients who experience relapse.


Pediatric Blood & Cancer | 2008

Outcome of children less than three years old at diagnosis with non-metastatic medulloblastoma treated with chemotherapy on the "Head Start" I and II protocols.

Girish Dhall; Howard Grodman; Lingyun Ji; Stephen A. Sands; Sharon Gardner; Ira J. Dunkel; Geoffrey McCowage; Blanca Diez; Jeffrey C. Allen; Anjali Gopalan; Albert S. Cornelius; Amanda M. Termuhlen; Minnie Abromowitch; Richard Sposto; Jonathan L. Finlay

To determine the survival of infants and young children with non‐metastatic medulloblastoma using intensive myeloablative chemotherapy and autologous hematopoietic progenitor cell rescue (AuHCR).

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Lingyun Ji

University of Southern California

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Jonathan L. Finlay

University of Southern California

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Jemily Malvar

Children's Hospital Los Angeles

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Shahab Asgharzadeh

Children's Hospital Los Angeles

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Paul S. Gaynon

University of Southern California

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Girish Dhall

Children's Hospital Los Angeles

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Robert C. Seeger

University of Southern California

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David R. Freyer

University of Southern California

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