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Dive into the research topics where Roger J. Packer is active.

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Featured researches published by Roger J. Packer.


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.


Journal of Clinical Oncology | 1999

Treatment of Children With Medulloblastomas With Reduced-Dose Craniospinal Radiation Therapy and Adjuvant Chemotherapy: A Children's Cancer Group Study

Roger J. Packer; Joel W. Goldwein; H. Stacy Nicholson; L. Gilbert Vezina; Jeffrey C. Allen; M. Douglas Ris; Karin M. Muraszko; Lucy B. Rorke; William M. Wara; Bruce H. Cohen; James M. Boyett

PURPOSE Medulloblastoma is the most common malignant brain tumor of childhood. After treatment with surgery and radiation therapy, approximately 60% of children with medulloblastoma are alive and free of progressive disease 5 years after diagnosis, but many have significant neurocognitive sequelae. This study was undertaken to determine the feasibility and efficacy of treating children with nondisseminated medulloblastoma with reduced-dose craniospinal radiotherapy plus adjuvant chemotherapy. PATIENTS AND METHODS Over a 3-year period, 65 children between 3 and 10 years of age with nondisseminated medulloblastoma were treated with postoperative, reduced-dose craniospinal radiation therapy (23.4 Gy) and 55.8 Gy of local radiation therapy. Adjuvant vincristine chemotherapy was administered during radiotherapy, and lomustine, vincristine, and cisplatin chemotherapy was administered during and after radiation. RESULTS Progression-free survival was 86% +/- 4% at 3 years and 79% +/- 7% at 5 years. Sites of relapse for the 14 patients who developed progressive disease included the local tumor site alone in two patients, local tumor site and disseminated disease in nine, and nonprimary sites in three. Brainstem involvement did not adversely affect outcome. Therapy was relatively well tolerated; however, the dose of cisplatin had to be modified in more than 50% of patients before the completion of treatment. One child died of pneumonitis and sepsis during treatment. CONCLUSION These overall survival rates compare favorably to those obtained in studies using full-dose radiation therapy alone or radiation therapy plus chemotherapy. The results suggest that reduced-dose craniospinal radiation therapy and adjuvant chemotherapy during and after radiation is a feasible approach for children with nondisseminated medulloblastoma.


Nature Genetics | 2001

Expression profiling of medulloblastoma : PDGFRA and the RAS/MAPK pathway as therapeutic targets for metastatic disease

Tobey J. MacDonald; Kevin M. Brown; Bonnie LaFleur; Katia M. Peterson; Christopher Lawlor; Yidong Chen; Roger J. Packer; Philip Cogen; Dietrich A. Stephan

Little is known about the genetic regulation of medulloblastoma dissemination, but metastatic medulloblastoma is highly associated with poor outcome. We obtained expression profiles of 23 primary medulloblastomas clinically designated as either metastatic (M+) or non-metastatic (M0) and identified 85 genes whose expression differed significantly between classes. Using a class prediction algorithm based on these genes and a leave-one-out approach, we assigned sample class to these tumors (M+ or M0) with 72% accuracy and to four additional independent tumors with 100% accuracy. We also assigned the metastatic medulloblastoma cell line Daoy to the metastatic class. Notably, platelet-derived growth factor receptor α (PDGFRA) and members of the downstream RAS/mitogen-activated protein kinase (MAPK) signal transduction pathway are upregulated in M+ tumors. Immunohistochemical validation on an independent set of tumors shows significant overexpression of PDGFRA in M+ tumors compared to M0 tumors. Using in vitro assays, we show that platelet-derived growth factor α (PDGFA) enhances medulloblastoma migration and increases downstream MAP2K1 (MEK1), MAP2K2 (MEK2), MAPK1 (p42 MAPK) and MAPK3 (p44 MAPK) phosphorylation in a dose-dependent manner. Neutralizing antibodies to PDGFRA blocks MAP2K1, MAP2K2 and MAPK1/3 phosphorylation, whereas U0126, a highly specific inhibitor of MAP2K1 and MAP2K2, also blocks MAPK1/3. Both inhibit migration and prevent PDGFA-stimulated migration. These results provide the first insight into the genetic regulation of medulloblastoma metastasis and are the first to suggest a role for PDGFRA and the RAS/MAPK signaling pathway in medulloblastoma metastasis. Inhibitors of PDGFRA and RAS proteins should therefore be considered for investigation as possible novel therapeutic strategies against medulloblastoma.


Journal of Clinical Oncology | 2001

Intellectual Outcome After Reduced-Dose Radiation Therapy Plus Adjuvant Chemotherapy for Medulloblastoma: A Children’s Cancer Group Study

M. Douglas Ris; Roger J. Packer; Joel W. Goldwein; Dana Jones-Wallace; James M. Boyett

PURPOSE To investigate the intellectual outcomes of children with medulloblastomas/primitive neuroectodermal tumors (MB/PNET) treated with reduced-dose craniospinal radiotherapy (RT) plus adjuvant chemotherapy. PATIENTS AND METHODS Forty-three children with average-risk posterior fossa MB/PNETs underwent longitudinal intelligence testing. All had been treated with a reduced-dose craniospinal RT regimen (23.4 Gy to the neuraxis, 32.4-Gy boost to the posterior fossa) and adjuvant chemotherapy. RESULTS The estimated rate of change from baseline was significant for Full Scale Intelligence Quotient (FSIQ), Verbal IQ (VIQ), and Nonverbal IQ (NVIQ) (P <.001 for all three outcomes). The rate of change was estimated to be -4.3 FSIQ points per year, -4.2 VIQ points per year, and -4.0 NVIQ points per year. Females were more subject to VIQ decline than were males (P =.008), and young children (< 7 years of age) were more negatively affected than were older children, with a significant decline in NVIQ (P =.016). Finally, patients with higher baseline evaluations suffered greater declines in IQ than did those with lower baseline scores. CONCLUSION This study represents the largest series of patients with average-risk MB/PNETs treated with a combination of reduced-dose RT and adjuvant chemotherapy whose intellectual development has been followed prospectively. Intellectual loss was substantial but suggestive of some degree of intellectual preservation compared with effects associated with conventional RT doses. However, this conclusion remains provisional, pending further research.


Journal of Clinical Oncology | 2009

The Childhood Cancer Survivor Study: A National Cancer Institute–Supported Resource for Outcome and Intervention Research

Leslie L. Robison; Gregory T. Armstrong; John D. Boice; Eric J. Chow; Stella M. Davies; Sarah S. Donaldson; Daniel M. Green; Sue Hammond; Anna T. Meadows; Ann C. Mertens; John J. Mulvihill; Paul C. Nathan; Joseph P. Neglia; Roger J. Packer; Preetha Rajaraman; Charles A. Sklar; Marilyn Stovall; Louise C. Strong; Yutaka Yasui; Lonnie K. Zeltzer

Survival for childhood cancer has increased dramatically over the last 40 years with 5-year survival rates now approaching 80%. For many diagnostic groups, rapid increases in survival began in the 1970s with the broader introduction of multimodality approaches, often including combination chemotherapy with or without radiation therapy. With this increase in rates of survivorship has come the recognition that survivors are at risk for adverse health and quality-of-life outcomes, with risk being influenced by host-, disease-, and treatment-related factors. In 1994, the US National Cancer Institute funded the Childhood Cancer Survivor Study, a multi-institutional research initiative designed to establish a large and extensively characterized cohort of more than 14,000 5-year survivors of childhood and adolescent cancer diagnosed between 1970 and 1986. This ongoing study, which reflects the single most comprehensive body of information ever assembled on childhood and adolescent cancer survivors, provides a dynamic framework and resource to investigate current and future questions about childhood cancer survivors.


Journal of the National Cancer Institute | 2009

Long-Term Outcomes Among Adult Survivors of Childhood Central Nervous System Malignancies in the Childhood Cancer Survivor Study

Gregory T. Armstrong; Qi Liu; Yutaka Yasui; Sujuan Huang; Kirsten K. Ness; Wendy Leisenring; Melissa M. Hudson; Sarah S. Donaldson; Allison King; Marilyn Stovall; Kevin R. Krull; Leslie L. Robison; Roger J. Packer

BACKGROUND Adult survivors of childhood central nervous system (CNS) malignancies are at high risk for long-term morbidity and late mortality. However, patterns of late mortality, the long-term risks of subsequent neoplasms and debilitating medical conditions, and sociodemographic outcomes have not been comprehensively characterized for individual diagnostic and treatment groups. METHODS We collected information on treatment, mortality, chronic medical conditions, and neurocognitive functioning of adult 5-year survivors of CNS malignancies diagnosed between 1970 and 1986 within the Childhood Cancer Survivor Study. Using competing risk framework, we calculated cumulative mortality according to cause of death and cumulative incidence of subsequent neoplasms according to exposure and dose of cranial radiation therapy (RT). Neurocognitive impairment and socioeconomic outcomes were assessed with respect to dose of CNS radiotherapy to specific brain regions. Cumulative incidence of chronic medical conditions was compared between survivors and siblings using Cox regression models. All tests of statistical significance were two-sided. RESULTS Among all eligible 5-year survivors (n = 2821), cumulative late mortality at 30 years was 25.8% (95% confidence interval [CI] = 23.4% to 28.3%), due primarily to recurrence and/or progression of primary disease. Patients who received cranial RT of 50 Gy or more (n = 813) had a cumulative incidence of a subsequent neoplasm within the CNS of 7.1% (95% CI = 4.5% to 9.6%) at 25 years from diagnosis compared with 1.0% (95% CI = 0% to 2.3%) for patients who had no RT. Survivors had higher risk than siblings of developing new endocrine, neurological, or sensory complications 5 or more years after diagnosis. Neurocognitive impairment was high and proportional to radiation dose for specific tumor types. There was a dose-dependent association between RT to the frontal and/or temporal lobes and lower rates of employment, and marriage. CONCLUSIONS Survivors of childhood CNS malignancies are at high risk for late mortality and for developing subsequent neoplasms and chronic medical conditions. Care providers should be informed of these risks so they can provide risk-directed care and develop screening guidelines.


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 Oncology | 2003

Long-Term Neurologic and Neurosensory Sequelae in Adult Survivors of a Childhood Brain Tumor: Childhood Cancer Survivor Study

Roger J. Packer; James G. Gurney; Judy A. Punyko; Sarah S. Donaldson; Peter D. Inskip; Marilyn Stovall; Yutaka Yasui; Ann C. Mertens; Charles A. Sklar; H. Stacy Nicholson; Lonnie K. Zeltzer; Joseph P. Neglia; Leslie L. Robison

PURPOSE To describe the neurologic and neurosensory deficits in children with brain tumors (BTs), compare incidence of these deficits with that of a sibling control group, and evaluate the factors associated with the development of these deficits. PATIENTS AND METHODS Detailed questionnaires were completed on 1,607 patients diagnosed between 1970 and 1986 with a primary CNS tumor. Neurosensory and neurologic dysfunctions were assessed and results compared with those of a sibling control group. Medical records on all patients were abstracted, including radiotherapy dose and volume. RESULTS Seventeen percent of patients developed neurosensory impairment. Relative to the sibling comparison group, patients surviving BTs were at elevated risk for hearing impairments (relative risk [RR], 17.3; P = <.0001), legal blindness in one or both eyes (RR, 14.8; P = <.0001), cataracts (RR, 11.9; P = <.0001), and double vision (RR, 8.8; P = <.0001). Radiation exposure greater than 50 Gy to the posterior fossa was associated with a higher likelihood of developing any hearing impairment. Coordination and motor control problems were reported in 49% and 26%, respectively, of survivors. Children receiving at least 50 Gy to the frontal brain regions had a moderately elevated risk for motor problems (RR, 2.0; P <.05). Seizure disorders were reported in 25% of patients, including 6.5% who had a late first occurrence. Radiation dose of 30 Gy or more to any cortical segment of the brain was associated with a two-fold elevated risk for a late seizure disorder. CONCLUSION Children surviving BTs are at significant risk for both early and late neurologic or neurosensory sequelae. These sequelae need to be prospectively monitored.


Journal of Clinical Oncology | 1993

Carboplatin and vincristine for recurrent and newly diagnosed low-grade gliomas of childhood.

Roger J. Packer; B Lange; J Ater; H S Nicholson; Jeffrey C. Allen; R Walker; Michael D. Prados; Regina I. Jakacki; Gregory H. Reaman; M N Needles

PURPOSE This study investigates the response rate to and toxicity of carboplatin and vincristine in children with recurrent low-grade gliomas (LGGs) or patients younger than 60 months with newly diagnosed LGGs. PATIENTS AND METHODS Twenty-three children with recurrent and 37 children with newly diagnosed LGGs were treated with a 10-week induction cycle of carboplatin and vincristine, followed by maintenance treatment with the same drugs. Patients were evaluated for response to treatment and toxicity. RESULTS Twelve of 23 (52% +/- 10%; 95% confidence interval [CI], 0.32 to 0.72) assessable children with recurrent disease had an objective response to treatment, which included a greater than 50% reduction in tumor size in seven of 23 (30% +/- 10%; 95% CI, 0.10 to 0.50). Twenty-three of 37 (62% +/- .08; 95% CI, 0.46 to 0.78) of newly diagnosed patients had an objective response, 16 of 37 (43% +/- 0.08%; 95% CI, 0.27 to 0.59) with greater than 50% reduction in tumor size. The majority of those with an objective response had diencephalic tumors (n = 29), but children with thalamic (n = 2), cortical (n = 1), and brain stem (n = 2) LGGs also responded to treatment. Of the 35 patients with objective response to treatment, the maximum response was seen in 25 after completion of induction and in the remaining 10 after two to six cycles of maintenance treatment. Forty-nine of 53 (92% +/- .04%) patients who were stable or improved after induction remain without progressive disease (PD). Hematologic toxicity was common, but resulted in cessation of therapy in only one patient. Six children have been removed from the study because of allergic reactions, which were considered to be carboplatin-associated. CONCLUSION Carboplatin and vincristine have activity in children with recurrent and newly diagnosed progressive LGGs. Objective responses to treatment after chemotherapy can be seen. This drug regimen is relatively well tolerated, and further studies are indicated to define the role of this combination of drugs in children with newly diagnosed LGGs.


Neurosurgery | 1993

Magnetic resonance scans should replace biopsies for the diagnosis of diffuse brain stem gliomas: a report from the Children's Cancer Group.

A. Leland Albright; Roger J. Packer; Robert A. Zimmerman; Lucy B. Rorke; James M. Boyett; G. Denman Hammond

Childrens Cancer Group Protocol CCG-9882 was designed to determine the effectiveness of hyperfractionated radiation for the treatment of children and young adults with brain stem gliomas. The study opened for the accrual of patients on September 21, 1988, and was closed on June 30, 1991. The first 54 children in the study were treated with irradiation doses of 100 cGy given twice daily to a total dosage of 7200 cGy. The next 66 children were treated with a similar daily regimens to a total of 7800 cGy. Tumors were diagnosed by clinical and radiographic criteria. Decisions about the need for surgery were left to the discretion of the treating neurosurgeon; tissue diagnosis did not alter the therapy in patients with diffuse infiltrating tumors. We reviewed the neuroradiology and neurosurgery reports as well as the pathological specimens of children entered on the study. By magnetic resonance (MR) imaging criteria, tumors involved the majority of the brain stem in 76% of cases; only three patients had tumors localized to the midbrain or medulla. Operations were performed on 56 of 120 patients (47%). Cerebrospinal fluid shunts were inserted in 27 (23%) of the children; insertion of a shunt was the only operation in 11, and a shunt was inserted in conjunction with a tumor operation in 16. Tumor operations were performed in 45 (38%) of the patients; 24 had stereotactic biopsies, and 21 had craniotomies. Of the 21 patients who had craniotomies, only biopsies were performed in 11; partial tumor resections were performed in 5 patients and subtotal resection in 5.(ABSTRACT TRUNCATED AT 250 WORDS)

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Robert F. Keating

Children's National Medical Center

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James Tait Goodrich

Albert Einstein College of Medicine

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Leslie N. Sutton

University of Pennsylvania

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James M. Boyett

St. Jude Children's Research Hospital

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Lucy B. Rorke

Children's Hospital of Philadelphia

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Javad Nazarian

Children's National Medical Center

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Stewart Goldman

Children's Memorial Hospital

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Luis Schut

Children's Hospital of Philadelphia

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Ian F. Pollack

Boston Children's Hospital

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Gilbert Vezina

Children's National Medical Center

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