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Robert J Wells

Publications and source records attributed to Robert J Wells.

11 recordsLinked to original sources
PubMed2007

Intensity of CNS treatment for pediatric cancer: prediction of social outcomes in survivors.

PURPOSE: To evaluate the association of central nervous system (CNS) treatment intensity and the social functioning of children who have completed treatment for leukemia, lymphoma, and solid tumors outside the CNS. Furthermore, we expected that these associations would be moderated by child age at diagnosis and gender. METHOD: Peer, teacher, and self-report data were obtained for 82 cancer survivors (age 9-17 years) using classroom rating and nomination procedures that are widely used in research on social development. Information regarding cranial radiation therapy (CRT), intrathecal chemotherapy (ITC), and systemic methotrexate were obtained from medical records and used to create a composite index of CNS treatment intensity. RESULTS: Higher scores on the index of CNS treatment intensity were associated with poorer peer acceptance, fewer friendships, greater social sensitivity-isolation, and diminished leadership-popularity based on peer-report. These associations were stronger for boys and children who were younger (<10 years old) at diagnosis. In contrast, CNS treatment intensity was only predictive of teacher-perceptions of aggressive-disruptive behavior and it was unrelated to social self-perceptions. CONCLUSION: These results suggest that children who receive CRT and ITC are at risk for problematic peer relations, particularly if they are male or younger at diagnosis. Given the stability of poor peer relationships and documented linkages between peer problems and subsequent academic and psychiatric difficulties, clinical services should address these issues. Research is needed to identify mechanisms that account for these outcomes and provide direction for prevention and treatment efforts.

Adolescent↗
PubMed2005

Clinical characteristics and outcome of children with Down syndrome and acute lymphoblastic leukemia: a Children's Cancer Group study.

We assessed the outcome of children with Down syndrome (DS) and acute lymphoblastic leukemia (ALL) receiving contemporary risk-based therapy by evaluating clinical and biologic features and outcome of children with ALL, with or without DS, enrolled in Children's Cancer Group (CCG) protocols between 1983 and 1995. Comparison of characteristics of children with ALL with (ALL-DS; n = 179) or without (ALL-NDS; n = 8268) DS showed no differences in initial white blood cell (WBC) count, central nervous system disease, and risk group. Children with ALL-DS did not present with unfavorable translocations and were older than 1 year of age at diagnosis with ALL. Event-free (56% vs 74%; P < .001) and disease-free (55% vs 73%; P < .001) survival at 10 years was significantly lower in the standard-risk ALL-DS population compared with ALL-NDS, but not in high-risk ALL-DS population (event-free survival, 62% vs 59%; P = .9; disease-free survival, 64% vs 59%; P = .9), and these differences persisted regardless of treatment era (early era [1983-1989] vs recent era [1989-1995]). Multivariate analysis revealed that presence of DS demonstrated an independent significant adverse prognostic effect for the standard-risk population, but not for the high-risk patients. These results suggest that intensification of therapy for patients with ALL-DS is needed to maintain outcome comparable with those of ALL-NDS patients.

Adolescent↗
PubMed2003

Mitoxantrone and cytarabine induction, high-dose cytarabine, and etoposide intensification for pediatric patients with relapsed or refractory acute myeloid leukemia: Children's Cancer Group Study 2951.

PURPOSE: To evaluate the response rate, survival, and toxicity of mitoxantrone and cytarabine induction, high-dose cytarabine and etoposide intensification, and further consolidation/maintenance therapies, including bone marrow transplantation, in children with relapsed, refractory, or secondary acute myeloid leukemia (AML). To evaluate response to 2-chlorodeoxyadenosine (2-CDA) and etoposide (VP-16) in patients who did not respond to mitoxantrone and cytarabine. PATIENTS AND METHODS: Patients with relapsed/refractory AML (n = 101) and secondary AML (n = 13) were entered. RESULTS: Mitoxantrone and cytarabine induction achieved a remission rate of 76% for relapsed/refractory patients and 77% for patients with secondary AML, with a 3% induction mortality rate. Cytarabine and etoposide intensification exceeded the acceptable toxic death rate of 10%. The response rate of 2-CDA/VP-16 was 8%. Two-year overall survival was estimated at 24% and was better than historical control data. Patients with secondary AML had similar outcomes to relapsed or refractory patients. Initial remission longer than 1 year was the most important prognostic factor for patients with primary AML (2-year survival rate, 75%), whereas for patients with primary AML, with less than 12 months of initial remission, survival was 13% and was similar to that of refractory patients (6%). CONCLUSION: Mitoxantrone and cytarabine induction is effective with reasonable toxicity in patients with relapsed/refractory or secondary AML. The cytarabine and etoposide intensification regimen should be abandoned because of toxicity. Patients with relapsed AML with initial remissions longer than 1 year have a relatively good prognosis.

Adolescent↗
PubMed2003

Extramedullary leukemia in children with newly diagnosed acute myeloid leukemia: a report from the Children's Cancer Group.

OBJECTIVES: To describe features of patients with acute myeloid leukemia presenting with extramedullary leukemic tumors (EML). METHODS: Among 1,832 patients entered on Children's Cancer Group's chemotherapy trials with acute myeloid leukemia, 199 patients had EML, defined as any leukemic collection outside the bone marrow cavity. Three patient groups were denoted: group 1 (n=109) with EML involving skin (with or without other sites of EML), group 2 (n=90) with EML in sites other than skin, and group 3 (n=1,633) without EML. RESULTS: The incidence of EML was 10.9%. Group 1 patients tended to be younger, had higher white blood cell counts, were more often CNS positive, had FAB M4 or M5 subtypes, and possessed more abnormalities of chromosome 11 than group 3 patients. Group 2 patients were younger, more often had the FAB M2 subtype, and had a higher incidence of t(8;21)(q22;q22) abnormality than group 3, but had similar white blood cell counts and incidence of CNS positivity at diagnosis. For group 1 the 5-year event-free survival was 26%, significantly worse than for group 3 at 29%. Event-free survival was better for group 2 patients (5-year estimate 46%), which remained a favorable prognostic factor by multivariate analysis. The authors retrospectively determined whether 118 (59%) of the EML patients received localized radiotherapy to the site of EML: 42 did and 76 did not. There were no differences in estimated event-free survival between patients who did and did not receive radiotherapy. CONCLUSIONS: Non-skin (group 2) EML appeared to be an independent favorable prognostic factor. Localized radiotherapy to the site of EML at the end of induction chemotherapy did not improve outcome.

Adolescent↗
PubMed2002

Quantitative nuclear magnetic resonance (QNMR) spectroscopy for assessing the purity of technical grade agrochemicals: 2,4-dichlorophenoxyacetic acid (2,4-D) and sodium 2,2-dichloropropionate (Dalapon sodium).

Comparison of quantitative NMR spectroscopy (QNMR) with chromatographic methods such as gas chromatography (GC) or high-pressure liquid chromatography (HPLC) for the determination of the purity of and impurities in technical grade agrochemicals, 2,4-dichlorophenoxyacetic acid (2,4-D), 1, and Dalapon sodium (sodium 2,2-dichloropropionate), 10, has revealed that QNMR is more precise and accurate than the chromatographic methods. Quantitative impurity profiling of technical grade 1 is rapid and accurate using 600 MHz (1)H NMR. Extra dispersion at the relatively high frequency allowed full assignment of the NMR spectrum of 1 and its related organic impurities in technical samples. The percentage purity of 1 was measured by the difference QNMR method, which involves summing the amounts of impurities and subtracting from 100%. Results are superior in consistency to those obtained by chromatographic methods. The percentage purity of Dalapon sodium, 10, in technical grade batches is readily obtained by (1)H QNMR, using either the difference method or the internal standard method, using dimethyl sulfone (DMSO2) internally as a reference material, that is chemically unrelated to the analyte. The latter method also allows the simultaneous identification and quantification of impurities, many of which are either not accessible to or detectable by the chromatographic methods. Uncertainty budgets for the QNMR method are presented and demonstrate that the major contributors to uncertainty lie in the weighing of the chemicals and in purity of the standard reference material prior to the QNMR experiment.

2,4-Dichlorophenoxyacetic Acid↗
PubMed2002

Phase I trial of cisplatin and topotecan in children with recurrent solid tumors: Children's Cancer Group Study 0942.

OBJECTIVES: To determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of cisplatin after a 72-hour continuous infusion of topotecan. PATIENTS AND METHODS: Thirty-six children younger than age 22 years (range 3-21) with recurrent solid tumors were treated with cisplatin 45 to 75 mg/m2 infused over the course of 6 hours, followed by a 72-hour continuous infusion of topotecan 0.75 or 1 mg/m2 per day, followed by granulocyte colony stimulating factor (G-CSF), either immediately after treatment or when neutropenia developed. Patients were stratified by the presence of bone marrow tumor involvement and previous radiation to the bone marrow. RESULTS: The DLT was neutropenia (absolute neutrophil count <500/microL for >7 days). The MTD was cisplatin 60 mg/m2 and topotecan 1 mg/m2 per day followed by G-CSF starting 24 hours after chemotherapy for patients without marrow involvement or previous radiation to the bone marrow. An acceptable MTD was not found for patients with previous radiation to the bone marrow or bone marrow involvement or without the use of G-CSF starting 24 hours after chemotherapy was completed. Topotecan clearance and steady-state levels were determined. Limited evidence for antitumor activity with this combination was found in rhabdomyosarcoma. CONCLUSIONS: The recommended dose for phase II trials is cisplatin 60 mg/m2 followed by a 72-hour infusion of topotecan 1 mg/m2 per day with G-CSF starting 24 hours after the completion of topotecan.

Adolescent↗