Risk-group-specific dose finding based on an average toxicity score.
Ontology highlight
ABSTRACT:
SUBMITTER: Bekele BN
PROVIDER: S-EPMC4570736 | biostudies-literature | 2010 Jun
REPOSITORIES: biostudies-literature
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2011-07-18 | E-GEOD-13861 | biostudies-arrayexpress
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Project description:Despite continual efforts to establish pre-operative prognostic model of gastric cancer by using clinical and pathological parameters, a staging system that reliably separates patients with early and advanced gastric cancer into homogeneous groups with respect to prognosis does not exist. With use of microarray and quantitative RT-PCR technologies, we exploited series of experiments in combination with complementary data analyses on tumor specimens from 161 gastric cancer patients. Various statistical analyses were applied to gene expression data to uncover subgroups of gastric cancer, to identify potential biomarkers associated with prognosis, and to construct molecular predictor of risk from identified prognostic biomarkers.Two subgroups of gastric cancer with strong association with prognosis were uncovered. The robustness of prognostic gene expression signature was validated in independent patient cohort with use of support vector machines prediction model. For easy translation of our finding to clinics, we develop scoring system based on expression of six genes that can predict the likelihood of recurrence after curative resection of tumors. In multivariate analysis, our novel risk score was an independent predictor of recurrence (P=0.004) in cohort of 96 patients, and its robustness was validated in two other independent cohorts. We identified novel prognostic subgroups of gastric cancer that are distinctive in gene expression patterns. Six-gene signature and risk score derived from them has been validated for predicting the likelihood of survival at diagnosis.
2011-07-19 | GSE13861 | GEO
Project description:Two useful strategies to speed up drug development are to increase the patient accrual rate and use novel adaptive designs. Unfortunately, these two strategies often conflict when the evaluation of the outcome cannot keep pace with the patient accrual rate and thus the interim data cannot be observed in time to make adaptive decisions. A similar logistic difficulty arises when the outcome is late-onset. Based on a novel formulation and approximation of the likelihood of the observed data, we propose a general methodology for model-assisted designs to handle toxicity data that are pending due to fast accrual or late-onset toxicity and facilitate seamless decision making in phase I dose-finding trials. The proposed time-to-event model-assisted designs consider each dose separately and the dose-escalation/de-escalation rules can be tabulated before the trial begins, which greatly simplifies trial conduct in practice compared to that under existing methods. We show that the proposed designs have desirable finite and large-sample properties and yield performance that is comparable to that of more complicated model-based designs. We provide user-friendly software for implementing the designs.
| S-EPMC8559898 | biostudies-literature
Project description:PurposeChildren with average-risk medulloblastoma (MB) experience survival rates of ≥ 80% at the expense of adverse consequences of treatment. Efforts to mitigate these effects include deintensification of craniospinal irradiation (CSI) dose and volume.MethodsACNS0331 (ClinicalTrials.gov identifier: NCT00085735) randomly assigned patients age 3-21 years with average-risk MB to receive posterior fossa radiation therapy (PFRT) or involved field radiation therapy (IFRT) following CSI. Young children (3-7 years) were also randomly assigned to receive standard-dose CSI (SDCSI; 23.4 Gy) or low-dose CSI (LDCSI; 18 Gy). Post hoc molecular classification and mutational analysis contextualized outcomes according to known biologic subgroups (Wingless, Sonic Hedgehog, group 3, and group 4) and genetic biomarkers. Neurocognitive changes and ototoxicity were monitored over time.ResultsFive hundred forty-nine patients were enrolled on study, of which 464 were eligible and evaluable to compare PFRT versus IFRT and 226 for SDCSI versus LDCSI. The five-year event-free survival (EFS) was 82.5% (95% CI, 77.2 to 87.8) and 80.5% (95% CI, 75.2 to 85.8) for the IFRT and PFRT regimens, respectively, and 71.4% (95% CI, 62.8 to 80) and 82.9% (95% CI, 75.6 to 90.2) for the LDCSI and SDCSI regimens, respectively. IFRT was not inferior to PFRT (hazard ratio, 0.97; 94% upper CI, 1.32). LDCSI was inferior to SDCSI (hazard ratio, 1.67%; 80% upper CI, 2.10). Improved EFS was observed in patients with Sonic Hedgehog MB who were randomly assigned to the IFRT arm (P = .018). Patients with group 4 MB receiving LDCSI exhibited inferior EFS (P = .047). Children receiving SDCSI exhibited greater late declines in IQ (estimate = 5.87; P = .021).ConclusionReducing the radiation boost volume in average-risk MB is safe and does not compromise survival. Reducing CSI dose in young children with average-risk MB results in inferior outcomes, possibly in a subgroup-dependent manner, but is associated with better neurocognitive outcome. Molecularly informed patient selection warrants further exploration for children with MB to be considered for late-effect sparing approaches.
| S-EPMC8376317 | biostudies-literature