Abstract #3184

McIntyre D, Waterton J, Robinson S, Worthington P, Griffiths J

Dynamic-contrast enhanced MRI is useful for assessing the affects of tumour vascular targeting agents. Two quantitative biomarkers have been recommended for clinical trials, both based on measuring the tissue [Gd] time course: integrated area under the [Gd]-time curve (IAUGC) and the pharmacokinetic transfer constant Ktrans. We have compared the statistical power of the methods in a retrospective analysis of pre-clinical studies of the vascular disrupting agent ZD6126 and the anti-angiogenic signalling inhibitor ZD6474. Neither method is consistently more sensitive at low dose, and we recommend IAUGC for its simplicity and robustness to fit failures.