title: Erratum to: Ungersma SE, Pacheco G, Ho C, Yee SF, Ross J, van Bruggen N, Peale FV Jr, Ross S, Carano RA. Vessel imaging with viable tumor analysis for quantification of tumor angiogenesis. Magn Reson Med 2010;63:1637–1647.
abstract: Imaging of tumor microvasculature has become an important tool for studying angiogenesis and monitoring antiangiogenic therapies. Ultrasmall paramagnetic iron oxide contrast agents for indirect imaging of vasculature offer a method for quantitative measurements of vascular biomarkers such as vessel size index, blood volume, and vessel density (Q). Here, this technique is validated with direct comparisons to ex vivo micro-computed tomography angiography and histologic vessel measurements, showing significant correlations between in vivo vascular MRI measurements and ex vivo structural vessel measurements. The sensitivity of the MRI vascular parameters is also demonstrated, in combination with a multispectral analysis technique for segmenting tumor tissue to restrict the analysis to viable tumor tissue and exclude regions of necrosis. It is shown that this viable tumor segmentation increases sensitivity for detection of significant effects on blood volume and Q by two antiangiogenic therapeutics [anti-vascular endothelial growth factor (anti-VEGF) and anti-neuropilin-1] on an HM7 colorectal tumor model. Anti-vascular endothelial growth factor reduced blood volume by 36±3% (p<0.0001) and Q by 52±3% (p<0.0001) at 48 h post-treatment; the effects of anti-neuropilin-1 were roughly half as strong with a reduction in blood volume of 18±6% (p<0.05) and a reduction in Q of 33±5% (p<0.05) at 48 h post-treatment.
authors: Department of Tumor Biology and Angiogenesis, South San Francisco, CA 94080, USA. sungersma@chla.usc.edu
authors: Sharon E
authors: SE
authors: Ungersma
authors: Glenn
authors: G
authors: Pacheco
authors: Calvin
authors: C
authors: Ho
authors: Sharon Fong
authors: SF
authors: Yee
authors: Jed
authors: J
authors: Ross
authors: Nicholas
authors: N
authors: van Bruggen
authors: Franklin V
authors: FV
authors: Peale
authors: Sarajane
authors: S
authors: Ross
authors: Richard A D
authors: RA
authors: Carano
mesh_terms: D000792:Angiography; D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy; D008279:Magnetic Resonance Imaging / Q000379:methods; D051379:Mice; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents