title: 3D MR angiography of intratumoral vasculature using a novel macromolecular MR contrast agent.
abstract: Noninvasive methods to visualize blood flow in the intratumoral vasculature have not previously been studied. In the present study, the use of a novel intravascular MR contrast agent with a generation-6 polyamidoamine dendrimer core (G6-(1B4M-Gd)192; MW: 175kD) was investigated, and the vasculature in experimental tumors was visualized using 3D MR angiography (MRA). Xenografted tumors in nude mice of two different histologies-KT005 (human osteogenic sarcoma) and LS180 (human colon carcinoma)-were used to obtain 3D MRA using G6-(1B4M-Gd)192 and Gd-DTPA. The contrast MR sectional images were correlated with the corresponding histological sections. The intratumoral vasculature in the KT005 tumor was clearly visualized by 3D MRA, which became more evident with the growth of the tumor xenograft. In contrast, the intratumoral vasculature in the LS180 tumor was sparser and much less developed than that in KT005 tumors. Blood vessels with a diameter as small as 100 microm based on histology were visualized using 0.033 mmol Gd/kg of G6-(1B4M-Gd)192. In conclusion, intratumoral vasculature with a 100-microm diameter was visualized better using 3D MRA with G6-(1B4M-Gd)192 than with Gd-DTPA.
authors.affiliation: Hitachi Medical Co. chair, Department of Diagnostic and Interventional Imagiology, Kyoto University, Kyoto, Japan. hisataka@kuhp.kyoto-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: N
authors.initials: N
authors.lastname: Sato
authors.forename: S
authors.initials: S
authors.lastname: Kawamoto
authors.forename: T
authors.initials: T
authors.lastname: Saga
authors.forename: A
authors.initials: A
authors.lastname: Hiraga
authors.forename: T
authors.initials: T
authors.lastname: Ishimori
authors.forename: J
authors.initials: J
authors.lastname: Konishi
authors.forename: K
authors.initials: K
authors.lastname: Togashi
authors.forename: M W
authors.initials: MW
authors.lastname: Brechbiel
mesh_terms: D000818:Animals; D003110:Colonic Neoplasms / Q000098:blood supply*; D003287:Contrast Media; D050091:Dendrimers; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000175:diagnosis*; D012516:Osteosarcoma / Q000098:blood supply*; D011073:Polyamines; D012039:Regional Blood Flow / Q000502:physiology; D012680:Sensitivity and Specificity; D014407:Tumor Cells, Cultured
chemical_list: D003287:Contrast Media; D050091:Dendrimers; C104700:PAMAM Starburst; D011073:Polyamines; D019786:Gadolinium DTPA