Yael Mardor, Presenter: Reseach consultant, Brainlab AG License agreement, Brainlab AG Research grant, The Kamin program of the Israeli Ministry of Industry & Commerce Research grant, Brainlab AG Donation, Roche Pharmaceuticals

David Guez, Abstract Co-Author: Nothing to Disclose

Galia Tsarfaty MPH, Abstract Co-Author: Nothing to Disclose

Gahl Greenberg, Abstract Co-Author: Nothing to Disclose

Dianne Daniels, Abstract Co-Author: Nothing to Disclose

Yuval Grober, Abstract Co-Author: Nothing to Disclose

Ouzi Nissim, Abstract Co-Author: Nothing to Disclose

Dvora Nass, Abstract Co-Author: Nothing to Disclose

Alisa Talianski, Abstract Co-Author: Nothing to Disclose

Roberto Spiegelmann, Abstract Co-Author: Nothing to Disclose

Sharona Salomon, Abstract Co-Author: Nothing to Disclose

Moshe Hadani, Abstract Co-Author: Nothing to Disclose

Andrew Kanner, Abstract Co-Author: Nothing to Disclose

Debora Blumenthal, Abstract Co-Author: Nothing to Disclose

Felix Bukstein, Abstract Co-Author: Nothing to Disclose

Michal Yalon, Abstract Co-Author: Nothing to Disclose

Jacob Zauberman, Abstract Co-Author: Nothing to Disclose

Jonathan Roth, Abstract Co-Author: Nothing to Disclose

Yigal Shoshan, Abstract Co-Author: Nothing to Disclose

Evgeniya Fridman, Abstract Co-Author: Nothing to Disclose

Marc Wygoda, Abstract Co-Author: Nothing to Disclose

Dror Limon, Abstract Co-Author: Nothing to Disclose

Tzahala Tzuk, Abstract Co-Author: Nothing to Disclose

Zvi R. Cohen, Abstract Co-Author: Nothing to Disclose

Leor Zach, Abstract Co-Author: Nothing to Disclose

Chen Chaim Hoffmann MD, Abstract Co-Author: Nothing to Disclose

David Last, Abstract Co-Author: Nothing to Disclose

Conventional MRI is unable to differentiate tumor/non-tumoral enhancing tissues on conventional T1-MRI (such as radionecrosis/pseudoprogression). We have applied delayed contrast MRI for calculating high resolution (1mm3) treatment response assessment maps (TRAMs) clearly differentiating tumor/non-tumoral tissues in brain tumor (BT) patients. The goal of the study was to validate the TRAMs histologically, to assess their application for patient management and to assess the added value of the TRAMs over rCBV and KTrans in differentiating tumor from treatment effects.

496 TRAMs were calculated for 151 patients with primary/metastatic BTs recruited/followed on study. The maps were validated by comparing pre-surgical maps of 51 resected patients with histology. Following initial validation, the maps were used for clinical decisions. The sensitivity and PPV of rCBV/KTranse (DSC/DCE MRI) to tumor regions in the TRAMs was studied in subgroups of 207/20 MRI exams.

Histological validation confirmed that regions of efficient clearance of the contrast agent >1hr post contrast injection represent morphologically active tumor while regions of contrast accumulation represent non-tumor tissues with 100% sensitivity and 92% PPV to active tumor regions. Following initial validation, the maps were used for making 232 clinical decisions. In 67 cases the decision was to continue follow-up and in 165 to change treatment (surgery, chemoradiation, radiation treatments, switch to Avastin, etc). The sensitivity and PPV of rCBV/KTrans to tumor regions in the TRAMs were found to be 23%/17% and 100%/90%, respectively.

Delayed MRI enables complete separation between tumor (negative signal) and treatment effects (positive signal) with high sensitivity and PPV and is currently being used for clinical decisions by 25 physicians referring patients to the study. In addition, the high resolution TRAMs may also be used for planning high precision treatments. The high PPV of rCBV/KTrans assures that high values of these parameters reflect tumor, but the low sensitivity suggests that most tumors (77%/83%) depicted in the TRAMs will result in false negative values.

Delayed contrast MRI provides high resolution differentiation between tumor/treatment-effects in brain tumor patients and therefore may be applied for decision making and treatment planning

Mardor, Y, Guez, D, Tsarfaty, G, Greenberg, G, Daniels, D, Grober, Y, Nissim, O, Nass, D, Talianski, A, Spiegelmann, R, Salomon, S, Hadani, M, Kanner, A, Blumenthal, D, Bukstein, F, Yalon, M, Zauberman, J, Roth, J, Shoshan, Y, Fridman, E, Wygoda, M, Limon, D, Tzuk, T, Cohen, Z, Zach, L, Hoffmann, C, Last, D, Delayed Contrast MRI for High Resolution Differentiation between Tumor/Non-tumor Tissue in Brain Tumor Patients – Comparison with DSC and DCE.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14006685.html