title: Clinical Utility of SPECT/CT Imaging Post-Radioiodine Therapy: Does It Enhance Patient Management in Thyroid Cancer?
abstract: BACKGROUND
  The aim of this study was to evaluate post-therapy iodine-131 single-photon emission computed tomography/computed tomography ((131)I-SPECT/CT) imaging in comparison to conventional planar (131)I whole-body imaging, and to assess its clinical impact on the management of patients.
  
  
  METHODS
  We retrospectively reviewed planar (131)I whole-body and (131)I-SPECT/CT imaging findings in 67 patients who underwent (131)I therapy for thyroid cancer. Two nuclear medicine physicians reviewed the scans independently. The foci of increased tracer uptake were identified in the neck, thorax and elsewhere. Within the neck, the foci of (131)I-increased uptake were graded qualitatively as probable or definite uptake in thyroid remnants and probable or definite uptake in the lymph nodes. Serum thyroglobulin level, histopathology and other imaging findings served as the reference standard.
  
  
  RESULTS
  Of the 67 patients, 57 (85%) had radioiodine avid disease and 10 (15%) demonstrated non-radioiodine avid disease. Overall, post-therapy (131)I-SPECT/CT downstaged lymph node staging in 10 patients and upstaged it in 4 patients. This translated into a change of management for 9/57 (16%) patients with radioiodine avid disease. A change of management was observed in 5/10 patients with non-radioiodine avid disease confirmed in the post-(131)I-SPECT/CT study. Additionally, clinically significant findings such as incidental lung cancer, symptomatic pleural effusion and consolidation were also diagnosed in both groups of patients.
  
  
  CONCLUSIONS
  In patients with thyroid cancer, (131)I-SPECT/CT is a valuable addition to standard post-therapy planar imaging. SPECT/CT also improved diagnostic confidence and provided crucial clinical information leading to change of management for a significant number of these patients.
authors.affiliation: Nuclear Medicine Department, Borough Wing, Guy's Hospital, London, UK.
authors.forename: Fahim U
authors.initials: FU
authors.lastname: Hassan
authors.affiliation: Nuclear Medicine Department, Borough Wing, Guy's Hospital, London, UK.
authors.forename: Hosahalli K
authors.initials: HK
authors.lastname: Mohan
keywords: Radioiodine; Single-photon emission computed tomography/computed tomography; Thyroid cancer
references.citation: Semin Nucl Med. 2011 Mar;41(2):121-38
references.pmid: 21272686
references.citation: AJR Am J Roentgenol. 2008 Dec;191(6):1785-94
references.pmid: 19020251
references.citation: JAMA. 2006 May 10;295(18):2164-7
references.pmid: 16684987
references.citation: Clin Nucl Med. 1995 Oct;20(10 ):869-75
references.pmid: 8616989
references.citation: AJR Am J Roentgenol. 2010 Sep;195(3):730-6
references.pmid: 20729453
references.citation: J Nucl Med. 2010 Sep;51(9):1361-7
references.pmid: 20720058
references.citation: Eur J Nucl Med Mol Imaging. 2010 Aug;37(8):1462-6
references.pmid: 20358197
references.citation: J Nucl Med. 2003 Dec;44(12 ):1905-10
references.pmid: 14660715
references.citation: Int J Cancer. 1991 Apr 22;48(1):28-33
references.pmid: 2019455
references.citation: Eur J Endocrinol. 2010 Jun;162(6):1131-9
references.pmid: 20212015
references.citation: Eur Radiol. 2001;11(10):1968-74
references.pmid: 11702130
references.citation: J Otolaryngol. 1994 Oct;23(5):360-5
references.pmid: 7807641
references.citation: J Nucl Med. 2008 Dec;49(12):1952-7
references.pmid: 18997044
references.citation: Br J Cancer. 1993 Feb;67(2):330-40
references.pmid: 8431362
references.citation: J Nucl Med. 2009 Jan;50(1):18-23
references.pmid: 19091884
references.citation: J Nucl Med. 2009 Feb;50(2):184-90
references.pmid: 19164225
references.citation: Int J Radiat Oncol Biol Phys. 2007;69(2 Suppl):S92-7
references.pmid: 17848306
references.citation: Eur J Nucl Med Mol Imaging. 2010 Apr;37(4):699-705
references.pmid: 19936746