Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Longitudinal dynamic contrast enhanced MRI studies were undertaken to monitor therapy induced volumetric and vascular changes. Three study components are presented in this work: one animal tumor chemotherapy study (R3230 AC adenocarcinoma treated with Taxotere), one patient with invasive lobular breast cancer undergoing neoadjuvant chemotherapy (AC regimen), and one patient with brain metastasis of primary breast cancer undergoing radiation therapy (40 Gray whole brain irradiation). In the animal study two contrast media with different molecular weights, Gadodiamide and Gadomer-17, were used. Only Gadomer-17 revealed significant changes in vascular properties. The responders showed decreased V(b) (vascular volume index) and K(2) (out-flux transport rate), which preceded tumor regression. The control tumors showed increased V(b) and K(2), before tumor growth became much faster. In the patient undergoing neoadjuvant therapy, the tumor was shrinking by 45% after 2 cycles of treatment, then again by 45% after 2 additional cycles. K(2) was decreasing over time with treatment. In the patient with brain metastasis, the 2 follow-up studies were much longer apart to monitor the regression and relapse of lesions. The pre-treatment volumes of lesions in the group without recurrence were significantly smaller compared to those with recurrence. In summary, the tumor volume was more sensitive than the vascular parameters measured by the small extracellular contrast medium for the assessment of therapy response and prediction of recurrence. The vascular properties measured by macromolecular contrast medium may have the potential to serve as early therapeutic efficacy indicators.
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PMID:Measurement of volumetric and vascular changes with dynamic contrast enhanced MRI for cancer therapy monitoring. 1262 75

It has been shown that magnetic resonance spectroscopy (MRS) can improve the specificity of the MR examination by the spectroscopic detection of choline (Cho). Commonly, the lesion is first visualized on postcontrast studies, and the MRS voxel is prescribed accordingly. The implicit assumption made in this approach is that the presence of gadolinium-based contrast agents will have a negligible effect on the MR spectra obtained from the lesion. In this work, we examined this assumption by determining the effects of six gadolinium-based contrast agents: Magnevist, Multihance, Omniscan, Optimark, ProHance, and Dotarem, on the Cho peak in phantoms and in a rat model for breast cancer. We found that only the three negatively-charged chelates: Magnevist, MultiHance, and Dotarem, broadened the Cho peak in phantoms and reduced the area of the Cho peak in vivo by an average of about 40%. The use of negatively-charged chelates may lead to an underestimation of the levels of Cho present in human breast cancers, since most studies use MRS postcontrast administration. Therefore, we recommend the use of the neutral chelates in MRI/MRS studies of the breast.
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PMID:Interaction of gadolinium-based MR contrast agents with choline: implications for MR spectroscopy (MRS) of the breast. 1936 55