Dataset Information

Dynamic contrast-enhanced magnetic resonance imaging as a prognostic factor in predicting event-free and overall survival in pediatric patients with osteosarcoma.

ABSTRACT: The objective of this study was to prospectively evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as an early imaging indicator of tumor histologic response to preoperative chemotherapy and as a possible prognostic factor for event-free survival (EFS) and overall survival in pediatric patients with newly diagnosed, nonmetastatic osteosarcoma who were treated on a single, multi-institutional phase 2 trial.Three serial DCE-MRI examinations at week 0 (before treatment), week 9, and week 12 (tumor resection) were performed in 69 patients with nonmetastatic osteosarcoma to monitor the response to preoperative chemotherapy. Four DCE-MRI kinetic parameters (the influx volume transfer constant [K(trans) ], the efflux rate constant [k(ep) ], the relative extravascular extracellular space [v(e) ], and the relative vascular plasma space [v(p) ]) and the corresponding differences (?K(trans) , ?k(ep) , ?v(e) , and ?v(p) ) of averaged kinetic parameters between the outer and inner halves of tumors were calculated to assess their associations with tumor histologic response, EFS, and overall survival.The parameters K(trans) , v(e) , v(p) , and k(ep) decreased significantly from week 0 to week 9 and week 12. The parameters K(trans) , v(p) , and ?k(ep) at week 9 were significantly different between responders and nonresponders (P = .046, P = .021, and P = .008, respectively). These 3 parameters were indicative of histologic response. The parameter ?v(e) at week 0 was a significant prognostic factor for both EFS (P = .02) and overall survival (P = .03).DCE-MRI was identified as a prognostic factor for EFS and overall survival before treatment on this trial and was indicative of a histologic response to neoadjuvant therapy. Further studies are needed to verify these findings with other treatment regimens and establish the potential role of DCE-MRI in the development of risk-adapted therapy for osteosarcoma.

SUBMITTER: Guo J

PROVIDER: S-EPMC3310962 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Dynamic contrast-enhanced magnetic resonance imaging as a prognostic factor in predicting event-free and overall survival in pediatric patients with osteosarcoma.

Guo Junyu J Reddick Wilburn E WE Glass John O JO Ji Qing Q Billups Catherine A CA Wu Jianrong J Hoffer Fredric A FA Kaste Sue C SC Jenkins Jesse J JJ Ortega Flores Ximena C XC Quintana Juan J Villarroel Milena M Daw Najat C NC

Cancer 20111216 15

<h4>Background</h4>The objective of this study was to prospectively evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as an early imaging indicator of tumor histologic response to preoperative chemotherapy and as a possible prognostic factor for event-free survival (EFS) and overall survival in pediatric patients with newly diagnosed, nonmetastatic osteosarcoma who were treated on a single, multi-institutional phase 2 trial.<h4>Methods</h4>Three serial DCE-MRI examinations ...[more]

PMID: 22180392

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Dataset Information

Dynamic contrast-enhanced magnetic resonance imaging as a prognostic factor in predicting event-free and overall survival in pediatric patients with osteosarcoma.

Publications

Dynamic contrast-enhanced magnetic resonance imaging as a prognostic factor in predicting event-free and overall survival in pediatric patients with osteosarcoma.

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