Jeannine Missbach-Guentner, Abstract Co-Author: Nothing to Disclose

Christian Dullin, Presenter: Nothing to Disclose

Sarah Kimmina, Abstract Co-Author: Nothing to Disclose

Melanie Missbach, Abstract Co-Author: Nothing to Disclose

Friedrich D. Knollmann MD, PhD, Abstract Co-Author: Nothing to Disclose

Eckhardt H. Grabbe MD, Abstract Co-Author: Nothing to Disclose

Frauke Alves MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To detect and to quantify not only tumor growth but also other parameters of tumor progression such as necrosis and vascularization in a murine tumor model in vivo by using FP-VCT.

The CT system consists of a modified circular CT gantry and two amorphous silicon flat-panel X-ray detectors each of 20x20 cm2 with a matrix of 1024x1024 200 µm detector elements. Standard z-coverage is 4,21 cm per rotation at a rotation time of 8 sec. C57/BL6 mice at 3 months of age were injected subcutaneously (1 x 106 cells) with syngeneic B16F1 melanoma cells. Following tumor cell inoculation, scans of anesthetized mice were performed using Flat Panel Detector-Volume CT (FP-VCT) every third day. Contrast medium,150 l Isovist™300 (Schering, Berlin, Germany) was applied intravenously to each mouse before scan. Scanning parameters were 80 kVp and 100 mA. Axial images as well as multiplanar reconstruction (MPR) and volume rendering (VR) images were obtained and analyzed. At day 15 after tumor cell inoculation, mice were sacrificed and tumors were excised and embedded in paraffin for histological analysis. Sections were stained with hematoxylin-eosin.

In this murine melanoma model subcutaneous tumors could be clearly depicted and tumor growth could be evaluated over time. Moreover the system allows the presentation of density and density ratios within the tumors and thus delineating necrotic tissue, tumor tissue and blood vessels. This allows to detect reduction of tumor volume caused by induced necrosis within the tumor. Density and density ratios of tumors were confirmed by histological analysis.

Non-invasive imaging by Flat Panel Detector based VCT allows an accurate real time assessment of subcutaneously growing tumors by measuring tumor volumes. Furthermore, FP-VCT shows exactly structural changes within the tumors in longitudinal studies and their quantitative acquisition. By detecting alterations within the tumors, FP-VCT will be a useful tool to monitor tumor progression in vivo and to evaluate tumor response to anti-cancer therapies over the course of disease.

Missbach-Guentner, J, Dullin, C, Kimmina, S, Missbach, M, Knollmann, F, Grabbe, E, Alves, F, et al, , Detection of Morphological Changes of Subcutaneous Tumors in Mice Using Flat Panel Detector - Volume Computed Tomography.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4418332.html