TY - JOUR
T1 - The magnetic resonance shutter speed discriminates vascular properties of malignant and benign breast tumors in vivo
AU - Huang, Wei
AU - Li, Xin
AU - Morris, Elizabeth A.
AU - Tudorica, Luminita A.
AU - Seshan, Venkatraman E.
AU - Rooney, William D.
AU - Tagge, Ian
AU - Wang, Ya
AU - Xu, Jingang
AU - Springer, Charles S.
PY - 2008/11/18
Y1 - 2008/11/18
N2 - The pharmacokinetic analysis of dynamic-contrast-enhanced (DCE) MRI data yields Ktrans and kep, two parameters independently measuring the capillary wall contrast reagent transfer rate. The almost universally used standard model (SM) embeds the implicit assumption that equilibrium transcytolemmal water exchange is effectively infinitely fast. In analyses of routine DCE-MRI data from 22 patients with suspicious breast lesions initially ruled positive by institutional screening protocols, the SM K trans values for benign and malignant lesions exhibit considerable overlap. A form of the shutter-speed model (SSM), which allows for finite exchange kinetics, agrees with the SM Ktrans value for each of the 15 benign lesions. However, it reveals that the SM underestimates K trans for each of the seven malignant tumors in this population. The fact that this phenomenon is unique to malignant tumors allows their complete discrimination from the benign lesions, as validated by comparison with gold-standard pathology analyses of subsequent biopsy tissue samples. Likewise, the SM overestimates kep, particularly for the benign tumors. Thus, incorporation of the SSM into the screening protocols would have precluded all 68% of the biopsy/pathology procedures that yielded benign findings. The SM/SSM difference is well understood from molecular first principles.
AB - The pharmacokinetic analysis of dynamic-contrast-enhanced (DCE) MRI data yields Ktrans and kep, two parameters independently measuring the capillary wall contrast reagent transfer rate. The almost universally used standard model (SM) embeds the implicit assumption that equilibrium transcytolemmal water exchange is effectively infinitely fast. In analyses of routine DCE-MRI data from 22 patients with suspicious breast lesions initially ruled positive by institutional screening protocols, the SM K trans values for benign and malignant lesions exhibit considerable overlap. A form of the shutter-speed model (SSM), which allows for finite exchange kinetics, agrees with the SM Ktrans value for each of the 15 benign lesions. However, it reveals that the SM underestimates K trans for each of the seven malignant tumors in this population. The fact that this phenomenon is unique to malignant tumors allows their complete discrimination from the benign lesions, as validated by comparison with gold-standard pathology analyses of subsequent biopsy tissue samples. Likewise, the SM overestimates kep, particularly for the benign tumors. Thus, incorporation of the SSM into the screening protocols would have precluded all 68% of the biopsy/pathology procedures that yielded benign findings. The SM/SSM difference is well understood from molecular first principles.
KW - Cancer
KW - DCE
KW - MRI
KW - Screening
KW - Water exchange
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U2 - 10.1073/pnas.0711226105
DO - 10.1073/pnas.0711226105
M3 - Article
C2 - 19004780
AN - SCOPUS:56649117585
SN - 0027-8424
VL - 105
SP - 17943
EP - 17948
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 46
ER -