title: Monitoring the Growth of an Orthotopic Tumour Xenograft Model: Multi-Modal Imaging Assessment with Benchtop MRI (1T), High-Field MRI (9.4T), Ultrasound and Bioluminescence.
abstract: Research using orthotopic and transgenic models of cancer requires imaging methods to non-invasively quantify tumour burden. As the choice of appropriate imaging modality is wide-ranging, this study aimed to compare low-field (1T) magnetic resonance imaging (MRI), a novel and relatively low-cost system, against established preclinical techniques: bioluminescence imaging (BLI), ultrasound imaging (US), and high-field (9.4T) MRI.
  
  
  
  A model of colorectal metastasis to the liver was established in eight mice, which were imaged with each modality over four weeks post-implantation. Tumour burden was assessed from manually segmented regions.
  
  
  
  All four imaging systems provided sufficient contrast to detect tumours in all of the mice after two weeks. No significant difference was detected between tumour doubling times estimated by low-field MRI, ultrasound imaging or high-field MRI. A strong correlation was measured between high-field MRI estimates of tumour burden and all the other modalities (p < 0.001, Pearson).
  
  
  
  These results suggest that both low-field MRI and ultrasound imaging are accurate modalities for characterising the growth of preclinical tumour models.
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.|UCL Cancer Institute, London, United Kingdom.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Ramasawmy
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.|UCL Cancer Institute, London, United Kingdom.
authors.forename: S Peter
authors.initials: SP
authors.lastname: Johnson
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Roberts
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Stuckey
authors.affiliation: UCL Institute for Women's Health, London, United Kingdom.
authors.forename: Anna L
authors.initials: AL
authors.lastname: David
authors.affiliation: UCL Cancer Institute, London, United Kingdom.
authors.forename: R Barbara
authors.initials: RB
authors.lastname: Pedley
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Lythgoe
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.
authors.forename: Bernard
authors.initials: B
authors.lastname: Siow
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, London, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Walker-Samuel
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000556:secondary*; D008279:Magnetic Resonance Imaging / Q000379:methods; D051379:Mice; D064847:Multimodal Imaging / Q000379:methods*; D009368:Neoplasm Transplantation; D014183:Transplantation, Heterologous; D047368:Tumor Burden; D014463:Ultrasonography / Q000379:methods