dc.contributor.author | Kim, Jana | |
dc.contributor.author | Moestue, Siver Andreas | |
dc.contributor.author | Bathen, Tone Frost | |
dc.contributor.author | Kim, Eugene | |
dc.date.accessioned | 2019-09-24T07:43:40Z | |
dc.date.available | 2019-09-24T07:43:40Z | |
dc.date.created | 2019-09-23T11:50:41Z | |
dc.date.issued | 2019 | |
dc.identifier.citation | Tomography. 2019, 5 (3), 308-319. | nb_NO |
dc.identifier.issn | 2379-1381 | |
dc.identifier.uri | http://hdl.handle.net/11250/2618367 | |
dc.description.abstract | Effective transverse relaxivity of gadolinium-based contrast agents is often neglected in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Here, we assess time and tissue dependence of R2* enhancement and its impact on pharmacokinetic parameter quantification and treatment monitoring. Multiecho DCE-MRI was performed at 7 T on mice bearing subcutaneous TOV-21G human ovarian cancer xenografts (n 8) and on the transgenic adenocarcinoma of the mouse prostate (TRAMP) model (n 7). Subsequently, the TOV-21G tumor-bearing mice were treated with bevacizumab and rescanned 2 days later. Pharmacokinetic analysis (extended Tofts model) was performed using either the first echo signal only (standard singleecho DCE-MRI) or the estimated signal at TE 0 derived from exponential fitting of R2* relaxation (R2*- corrected). Neglecting R2* enhancement causes underestimation of Gd-DOTA concentration (peak enhancement underestimated by 9.4%–16% in TOV-21G tumors and 13%–20% in TRAMP prostates). Median Ktrans and ve were underestimated in every mouse (TOV-21G Ktrans: 11%–19%, TOV-21G ve: 5.3%–8.9%; TRAMP Ktrans: 8.6%–19%, TRAMP ve: 12%–21%). Bevacizumab treatment reduced Ktrans in all TOV-21G tumors after 48 hours. Treatment effect was significantly greater in all tumors after R2* correction (median change of 0.050 min1 in R2*-corrected Ktrans vs. 0.037 min1 in uncorrected Ktrans). R2* enhancement in DCEMRI is both time- and tissue-dependent and may not be negligible at 7 T in tissue with high Ktrans. This has consequences for the use of Ktrans and other DCE-MRI parameters as biomarkers, because treatment effect size can be underestimated when R2* enhancement is neglected. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | Grapho Publications | nb_NO |
dc.rights | Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal | * |
dc.rights | Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal | * |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/deed.no | * |
dc.title | R2* Relaxation Affects Pharmacokinetic Analysis of Dynamic Contrast-Enhanced MRI in Cancer and Underestimates Treatment Response at 7 T | nb_NO |
dc.type | Journal article | nb_NO |
dc.description.version | publishedVersion | nb_NO |
dc.source.pagenumber | 308-319 | nb_NO |
dc.source.volume | 5 | nb_NO |
dc.source.journal | Tomography | nb_NO |
dc.source.issue | 3 | nb_NO |
dc.identifier.doi | https://doi.org/10.18383/j.tom.2019.00015 | |
dc.identifier.cristin | 1727740 | |
dc.description.localcode | © 2019 The Authors. Published by Grapho Publications, LLC This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) | nb_NO |
cristin.unitcode | 194,65,25,0 | |
cristin.unitcode | 194,65,15,0 | |
cristin.unitname | Institutt for sirkulasjon og bildediagnostikk | |
cristin.unitname | Institutt for klinisk og molekylær medisin | |
cristin.ispublished | true | |
cristin.fulltext | original | |