16:00 |
0912. |
Effect of pantethine on
ovarian tumor progression and choline metabolism
Marie-France Penet1, Delia Mezzanzanica2,
Franca Podo3, Max de Reggi4,
Bouchra Gharib4, and Zaver M. Bhujwalla1
1JHU ICMIC Program, Division of Cancer
Imaging Research, The Johns Hopkins University School of
Medicine, Baltimore, MD, United States, 2Unit
of Molecular Therapies, Department of Experimental
Oncology and Molecular Medicine, Fondazione IRCCS
Istituto Nazionale dei Tumori, Milan, Italy,3Department
of Cell Biology and Neurosciences, Section of Molecular
and Cellular Imaging, Istituto Superiore di Sanità,
Rome, Italy, 4Neurobiology
of Cellular Interactions and Neuropathophysiology, UMR
CNRS 7259, Aix-Marseille University, Marseille, France
Epithelial ovarian cancer remains the leading cause of
death from gynecologic malignancy among women in
developed countries. New therapeutic strategies
evaluated with relevant preclinical models are urgently
needed to improve survival rates. Here we have assessed
the effect of pantethine on tumor growth and metabolism
using MRI and high resolution MRS, respectively, in an
orthotopic model of ovarian cancer. We also investigated
effects on metastases and ascites formation. Pantethine
treatment resulted in slower tumor progression,
decreased levels of phosphocholine and
phosphatidylcholine, and reduced metastases and ascites
occurrence.
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16:12 |
0913. |
Acquired resistance to
sunitinib is not associated with rescue angiogenesis in
786-O renal cell carcinoma xenografts -
permission withheld
Simon P Robinson1, Naveen S Vasudev2,
and Andrew R Reynolds2
1Division of Radiotherapy & Imaging, The
Institute of Cancer Research, Sutton, Surrey, United
Kingdom, 2Breakthrough
Breast Cancer Research Centre, The Institute of Cancer
Research, London, United Kingdom
The response of 786-O RCC xenografts to sunitinib was
investigated using susceptibility contrast MRI with
USPIO particles. Fractional blood volume (fBV) was
significantly reduced after 2 weeks daily treatment in
the absence of any change in tumour volume. This reduced
fBV was maintained in 786-O xenografts exhibiting
acquired resistance to sunitinib.
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16:24 |
0914.
|
Assessment of the response
of colorectal tumours to imatinib mesylate therapy using
carbogen and hypercapnia gas challenges
Miguel R. Goncalves1, Simon Walker-Samuel1,
Rajiv Ramasawmy1,2, Sean P. Johnson2,
R. Barbara Pedley2, and Mark F. Lythgoe1
1UCL Centre for Advanced Biomedical Imaging,
Division of Medicine, London, United Kingdom, 2UCL
Cancer Institute, London, United Kingdom
We present the results of a tumour therapy study with
the antiangiogenic agent imatinib mesylate, which was
assessed using gradient-echo MRI alongside hyperoxia and
hypercapnia challenges. Median carbogen-ΔR2*,
carbogen-ΔR1 and hypercapnia-ΔGRE-SI did not change with
therapy. However, significant changes in the spatial
heterogeneity of carbogen-ΔR2* and hypercapnia-ΔSI were
observed. These results are possibly due to the combined
effect of a number of localised phenomena, given the
heterogeneous nature of the tumour vasculature.
|
16:36 |
0915.
|
Imaging biomarkers of cell
death: a comparison between viscoelasticity and ADC in an
orthotopic breast cancer xenograft model
Jin Li1, Yann Jamin1, Jessica K.R.
Boult1, John C. Waterton2, Ralph
Sinkus3, Michelle D. Garrett4, and
Simon P. Robinson1
1Division of Radiotherapy & Imaging, The
Institute of Cancer Research, Sutton, Surrey, United
Kingdom, 2Personalised
Healthcare and Biomarkers, AstraZeneca, Macclesfield,
Cheshire, United Kingdom, 3BHF
Centre of Excellence, Division of Imaging Sciences and
Biomedical Engineering, King's College London, King's
Health Partners, St Thomas' Hospital, London, United
Kingdom, 4Division
of Cancer Therapeutics, The Institute of Cancer
Research, Sutton, Surrey, United Kingdom
Comparison of MRE-derived imaging biomarkers of
viscoelasticity (|G*|) and ADC in orthotopically
propagated BT474 breast cancer xenografts revealed a
close spatial association and quantitative correlation
of reduced |G*| and elevated ADC with
pathologically-confirmed cell death. A stronger and more
significant correlation between |G*| and cell death
supports |G*| as a potentially more sensitive biomarker
of cell death than ADC.
|
16:48 |
0916. |
MRI Evaluation of a
Peptide-Coated Nanoparticle as a Potential Therapy Against
Preclinical Brain Metastatic Breast Cancer
Amanda M Hamilton1, Sallouha Aidoudi-Ahmed2,
Venkata R Kotamraju2, Shweta Sharma2,
Paula J Foster1, Kazuki N Sugahara2,
Erkki Ruoslahti2, and Brian K Rutt3
1Robarts Research Institute, London, Ontario,
Canada, 2Sanford-Burnham
Medical Research Institute, California, United States, 3Stanford
University, California, United States
MRI was used to evaluate the treatment efficacy of iRGD-NW,
a magnetic nanoparticle coated with a tumor-penetrating
peptide in a preclinical breast cancer brain metastasis
model. Mice received saline, iRGD-NW (tumor-homing) or
CRGDC-NW at day (td) 6 or 12 post-cell injection. Tumor
formation was evaluated by MRI at two time points after
treatment administration. Td6 iRGD-NW mice displayed
significantly lower tumor burden and signal void
retention than that of saline mice. There was no
observed treatment effect for td12 mice. Results showed
that iRGD-NW had a significant time-dependent effect on
tumor burden and suggest a potential use in metastasis
prevention.
|
17:00 |
0917. |
Early therapy evaluation of
sunitinib for gastrointestinal stromal tumors using
quantitative perfusion and diffusion weighted magnetic
resonance imaging: a pilot study
Hyunki Kim1, Desiree Morgan1,
David Sarver2, Kyle Lee1, T.
Beasley1, and James Posey1
1University of Alabama at Birmingham,
Birmingham, AL, United States, 2University
of Arkansas for Medical Sciences, AR, United States
Quantitative DCE-MRI and DWI were successfully utilized
in GIST patients to measure the perfusion and diffusion
parameters of tumors. Significant decreases of Ktrans
and kep values were observed in GISTs after sunitinib
therapy, while tumor ADC values were significantly
increased likely reflecting favorable anti-tumor
effects. Tumor Ktrans change was significantly
correlated with tumor-volume change, and therefore it
may serve as an effective surrogate biomarker,
especially when applied at earlier time points, to
assess the therapeutic efficacy of sunitinib.
|
17:12 |
0918. |
Evidence for Caution in
DCE-MRI Assessment of Response to Antiangiogenic Therapy
Using the Reference Tissue Method
Wei Huang1, Aneela Afzal1, Megan L
Holtorf1, and Christopher W Ryan1
1Oregon Health & Science University,
Portland, Oregon, United States
DCE-MRI studies were performed on eight soft-tissue
sarcoma patients to assess responses to treatment
regimen of antiangiogenic agent plus conventinal
chemoradiotherapy. Significant Ktrans and kep decreases
were found in normal muscle regions adjacent to the
tumor following initial 2 weeks of antiangiogenic
therapy only. The results suggest that caution must be
taken in DCE-MRI evaluation of response to
antiangiogenic treatment using the reference tissue
method.
|
17:24 |
0919.
|
Multiparametric MRI
detection and prediction of response to neoadjuvant
chemotherapy in breast cancer.
Elizabeth AM O'Flynn1, David Collins2,
James D'Arcy2, Maria Schmidt2,
Kabir Mohammed3, and Nandita M deSouza1
1Clinical Magnetic Resonance, Institute of
Cancer Research and Royal Marsden Hospital, Sutton,
Surrey, United Kingdom, 2Clinical
Magnetic Resonance, Insitute of Cancer Research, Sutton,
Surrey, United Kingdom, 3Statistics,
Royal Marsden Hospital, Sutton, Surrey, United Kingdom
We investigate the role of multiparametric MRI in the
prediction of response to neoadjuvant chemotherapy (NAC)
in breast cancer. 27 women underwent breast MRI at 3T
prior to and after two cycles of NAC. Values for ADC,
R2*, Ktrans, ve, kep and IAUGC were recorded
pixel-by-pixel. The enhancement fraction (EF) was
calculated for each patient. The percentage decrease in
EF after 2 cycles was the best predictor of complete
pathological response on discriminant analysis. EF
should be considered as a potential biomarker for
predicting response to NAC.
|
17:36 |
0920. |
Quantitative DCE-MRI
Assessment of Breast Cancer Response to Neoadjuvant
Chemotherapy
Alina Tudorica1, Karen Y Oh1,
Stephen Y-C Chui1, Nicole Roy1,
Megan L Troxell1, Yiyi Chen1,
Arpana Naik1, Megan L Holtorf1,
Aneela Afzal1, Zunqiu Chen1,
Charles S Springer1, Xin Li1, and
Wei Huang1
1Oregon Health & Science University,
Portland, Oregon, United States
Fifteen women with breast cancer underwent DCE-MRI
before, during, and after neoadjuvant chemotherapy.
Pharmacokinetic analysis of DCE-MRI data were performed
using Standard (Tofts) model (SM) and Shutter-Speed
model (SSM). After only one cycle of therapy, % changes
in SM and SSM Ktrans and kep, and SSM-unique Tau_i, as
well as absolute values of Ktrans and kep, provieded
excellent early predictions of pathologic complete
response. Following therapy completion, tumor Tau_i was
inversely, while Ktrans and tumor size were positively,
correlated with residual disease burden. In conclusion,
DCE-MRI functional parameters provided earlier
prediction of response and more accurate assessment of
residual disease compared to tumor size measurement.
|
17:48 |
0921. |
Variations in DCE-MRI
Assessment of Breast Cancer Therapy Response: A Multicenter
Data Analysis Challenge
Wei Huang1, Xin Li1, Xia Li2,
Ming-Ching Chang3, Matthew J Oborski4,
Dariya I Malyarenko5, Mark Muzi6,
Guido H Jajamovich7, Andriy Fedorov8,
Yiyi Chen1, Alina Tudorica1,
Sandeep N Gupta3, Charles M Laymon4,
Kenneth I Marro6, Hadrien A Dyvorne7,
James V Miller3, Thomas L Chenevert5,
Thomas E Yankeelov2, James M Mountz4,
Paul E Kinahan6, Ron Kikinis8,
Bachir Taouli7, Fiona Fennessy8,
and Jayashree Kalpathy-Cramer9
1Oregon Health & Science University,
Portland, Oregon, United States, 2Vanderbilt
University, Nashville, Tennessee, United States, 3General
Electric Global Research, Niskayuna, New York, United
States, 4University
of Pittsburgh, Pittsburgh, Pennsylvania, United States, 5University
of Michigan, Ann Arbor, Michigan, United States, 6University
of Washington, Seattle, Washington, United States, 7Icahn
School of Medicine at Mount Sinai, New York, New York,
United States, 8Brigham
and Women’s Hospital and Harvard Medical School, Boston,
Massachusetts, United States, 9Massachusetts
General Hospital and Harvard Medical School, Boston,
Massachusetts, United States
Seven institutions of the NCI-sponsored Quantitative
Imaging Network (QIN) participated in a DCE-MRI data
analysis challenge, in which 12 pharmacokinetic
models/algorithms (including Tofts model, extended Tofts
model, and Shutter-Speed model) were used to analyze
shared breast DCE-MRI data collected at one center
before and after one cycle of neoadjuvant chemotherapy,
from 10 breast cancer patients. Tumor ROI definition,
AIF, and precontrast T1 were fixed for analysis of each
data set across all algorithms. Considerable variations
in DCE-MRI parameters were found among the algoritms
with Ktrans wCV as high as 0.59. Encouragingly, Ktrans
and kep values after one therapy cyles and their %
changes (relative to baselin) obtained from all
algorithms provided good to excellent early prediction
of pathologic response.
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