MicroCT for high‐resolution imaging of ectopic pheochromocytoma tumors in the liver of nude mice

Abstract

Successful outcomes for patients with cancer often depend on the early detection of tumor and the prompt initiation of active therapy. Despite major advances in the treatment of many cancers, early-stage lesions often go undetected due to the suboptimal resolution of current anatomical and functional imaging modalities. This limitation also applies to preclinical animal tumor models that are crucial for the evaluation and development of new therapeutic approaches to cancer. We report a new mouse model of metastatic pheochromocytoma, generated using tail vein injection of the mouse pheochromocytoma cell (MPC) line that reproducibly generated multiple liver tumors in the animals. Furthermore, we show that in vivo microCT imaging enhanced using a hepatobiliary-specific contrast agent, glyceryl-2-oleyl-1,3-di-7-(3-amino-2,4,6-triiodophenyl)-heptanoate (DHOG), detected tumors as small as 0.35 mm as early as 4 weeks after the injection of the tumor cells. This model may be useful for in vivo studies of tumor biology and for development of new strategies to treat metastatic pheochromocytoma. ' 2006 Wiley-Liss, Inc.

Time-Course of Contrast Enhancement in Spleen and Liver with Exia 160, Fenestra LC, and VC

“…Our results of Fenestra LC and VC support the findings of Ohta et al [26], Almajdub et al [27], Suckow and Stout [25], and Ford et al [13].…”

Contrast-Enhanced Microcomputed Tomography Using Intraperitoneal Contrast Injection for the Assessment of Tumor-Burden in Liver Metastasis Models

“…The total iodine dose of 25 mg is significantly below the reported values of 48 mg, 19 160 mg, 9 and 200 mg iodine 20 that have been administered previously to mice. In agreement with our preliminary dose finding study, which suggests that the contrast agents can be used simultaneously and are well tolerated, both iohexol 19 and Fenestra 5,21 have been used previously in longitudinal studies without apparent side effects. Specifically, Fenestra has been administered 4 times over a 5-week time period in a study of liver tumors in mice, 5 and in a study of myocardial remodeling postinfarction, 21 without any visible signs of toxicity.…”

“…1 It has been demonstrated that tumor cells lack the apolipoprotein E receptor and do not accumulate the lipid emulsion, leading to contrast between the unenhanced tumor and the enhanced liver parenchyma. 4,5 To achieve the full benefits of noninvasive imaging, the ability to identify and quantify tumor numbers, location and volume must be as simple, rapid and precise as possible. With a hepatocyte-selective contrast agent alone the vasculature is not enhanced in the micro-CT images, and resembles the equally unenhanced tumors, 5 which hampers efforts to use automated or semiautomated quantification methods.…”

“…4,5 To achieve the full benefits of noninvasive imaging, the ability to identify and quantify tumor numbers, location and volume must be as simple, rapid and precise as possible. With a hepatocyte-selective contrast agent alone the vasculature is not enhanced in the micro-CT images, and resembles the equally unenhanced tumors, 5 which hampers efforts to use automated or semiautomated quantification methods. A modified version of this hepatocyte-selective contrast agent 6 is retained in the blood stream while slowly being sequestered by the liver over a period of hours.…”

A microcomputed tomography guided fluorescence tomography system for small animal molecular imaging

“…A strong rationale for such a system is that microCT offers poor soft tissue contrast, limiting its in vivo tumor imaging abilities to a few anatomical sites, primarily the lungs and liver. [27][28][29] Contrast agents have been shown to improve results but very low x-ray tube voltages are still necessary to achieve adequate contrast, 30 often resulting in an unrealistically long acquisition times. As such, the incorporation of functional imaging capabilities from FT has the potential to enhance the information content in microCT images by providing increased sensitivity to detecting cancerous tissues.…”