title: Indirect magnetic resonance imaging lymphography identifies lymph node metastasis in rabbit pyriform sinus VX2 carcinoma using ultra-small super-paramagnetic iron oxide.
abstract: BACKGROUND
  USPIO is a contrast agent for MRI that can generate T2W images with low signal intensities. After subcutaneous or intravenous injection of USPIO, normal lymph node tissues uptake these nano-particles, but tumor cells do not. Thus, tumor metastasis can be detected using this contrast agent.
  
  
  OBJECTIVE
  The aim of this study was to access the feasibility of USPIO enhanced MRI for the detection of cervical lymph node metastasis in a pyriform sinus carcinoma animal model and to investigate the ability of USPIO to enhance images of cervical lymph node metastases.
  
  
  RESULTS
  Twenty New Zealand rabbits were randomly divided into tumor and inflammatory groups, and each group contained 10 rabbits. In the inflammatory group, a 0.5 ml egg yolk emulsion was injected into the sub-mandibular muscle of the rabbits to induce an inflammatory reaction in their cervical lymph nodes. In the tumor group, a VX2 tumor tissue suspension was transplanted into the pyriform sinus sub-mucosa of the rabbits using direct laryngoscope. Four weeks after the tumor or egg yolk injection, MRIs were performed before and after USPIO injection to observe the imaging enhancement features of USPIO. After that, a histo-pathological analysis was performed for all rabbits. We found the metastatic lymph nodes had no signal reduced intensity or irregular signal reduced intensity on T2-weighted image by using USPIO enhancement. In the tumor group,the sensitivity and specificity of plain MRI were 57.6% and 60.7%. The corresponding values of USPIO-enhanced MRl were 96.1% and 85.7%. (P<0.05).
  
  
  CONCLUSIONS
  The features and the extent of the lymph node metastases corresponded to those observed on USPIO-enhanced MR images. USPIO-enhanced MRI is useful for the detection and estimation of lymph node metastasis in this cervical carcinoma animal model.
authors.affiliation: Department of Otolaryngology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Na
authors.initials: N
authors.lastname: Shen
authors.affiliation: Department of Otolaryngology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tan
authors.affiliation: Department of Otolaryngology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Radiology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Pathology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Polymer Science, Fudan University, Shanghai, China.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Lv
authors.affiliation: Department of Otolaryngology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Xie
authors.affiliation: Department of Otolaryngology, ZhongShan Hospital, Fudan University, Shanghai, China.
authors.forename: Xinsheng
authors.initials: X
authors.lastname: Huang
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003911:Dextrans; D007249:Inflammation / Q000473:pathology; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008220:Lymphography / Q000379:methods*; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D056144:Pyriform Sinus / Q000000981:diagnostic imaging* / Q000473:pathology*; D011817:Rabbits
chemical_list: D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10
references.citation: Radiology. 2008 Mar;246(3):804-11
references.pmid: 18195379
references.citation: AJR Am J Roentgenol. 2001 Aug;177(2):343-8
references.pmid: 11461859
references.citation: Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2009 Apr;31(2):182-6
references.pmid: 19507597
references.citation: Adv Drug Deliv Rev. 1999 Apr 5;37(1-3):295-312
references.pmid: 10837741
references.citation: Surg Oncol Clin N Am. 2004 Jan;13(1):81-98
references.pmid: 15062363
references.citation: Clin Imaging. 2009 Jul-Aug;33(4):301-5
references.pmid: 19559353
references.citation: Anticancer Res. 2002 Nov-Dec;22(6A):3273-9
references.pmid: 12530075
references.citation: Magn Reson Imaging. 1998 Oct;16(8):917-23
references.pmid: 9814774
references.citation: Ann Anat. 2004 Aug;186(4):337-47
references.pmid: 15481841
references.citation: Eur J Radiol. 2006 Jun;58(3):367-74
references.pmid: 16472955
references.citation: Arch Otolaryngol Head Neck Surg. 1999 Dec;125(12):1322-8
references.pmid: 10604409
references.citation: Radiology. 2007 Jan;242(1):137-43
references.pmid: 17090719
references.citation: Lab Anim. 2003 Jan;37(1):37-43
references.pmid: 12626070
references.citation: Eur Radiol. 2001;11(11):2319-31
references.pmid: 11702180
references.citation: AJR Am J Roentgenol. 2000 Sep;175(3):759-66
references.pmid: 10954463
references.citation: Int J Radiat Oncol Biol Phys. 2012 Nov 1;84(3):712-8
references.pmid: 22417806
references.citation: Radiology. 1991 Feb;178(2):519-22
references.pmid: 1987619
references.citation: J Surg Oncol. 2001 Nov;78(3):151-6; discussion 157
references.pmid: 11745796
references.citation: Zhonghua Er Bi Yan Hou Ke Za Zhi. 2004 Dec;39(12):741-5
references.pmid: 15813018
references.citation: Cancer Imaging. 2009 Apr 06;9:19-28
references.pmid: 19414293
references.citation: Radiology. 1998 Jun;207(3):799-808
references.pmid: 9609907
references.citation: AJR Am J Roentgenol. 1993 Jul;161(1):193-200
references.pmid: 8517301
references.citation: N Engl J Med. 2003 Jun 19;348(25):2491-9
references.pmid: 12815134
references.citation: Eur Radiol. 2004 Jun;14(6):937-44
references.pmid: 14991323
references.citation: Head Neck. 2000 Jul;22(4):380-5
references.pmid: 10862022
references.citation: Breast Cancer. 2010 Oct;17(4):241-6
references.pmid: 19575282
references.citation: Acta Otolaryngol. 1989 Jul-Aug;108(1-2):152-60
references.pmid: 2763834
references.citation: Radiographics. 2004 May-Jun;24(3):867-78
references.pmid: 15143236
references.citation: Clin Radiol. 1994 Apr;49(4):241-5
references.pmid: 8162679
references.citation: ORL J Otorhinolaryngol Relat Spec. 2009;71(3):129-34
references.pmid: 19321975
references.citation: Radiology. 2004 Apr;231(1):91-9
references.pmid: 14976266
references.citation: Radiology. 2003 Sep;228(3):777-88
references.pmid: 12954896
references.citation: Gastric Cancer. 2009;12(1):6-22
references.pmid: 19390927
references.citation: J Vasc Res. 2007;44(2):119-28
references.pmid: 17215583
references.citation: Radiographics. 2003 Nov-Dec;23(6):1541-58; discussion 1559-60
references.pmid: 14615563