title: 68Ga-DOTATOC Imaging of Neuroendocrine Tumors: A Systematic Review and Metaanalysis.
abstract: 68Ga-DOTATOC, a somatostatin receptor-targeted ligand, has been used clinically in Europe over the past decade for imaging neuroendocrine tumors (NETs). It appears to be quite sensitive and effective for clinical management decision making. This metaanalysis summarizes the efficacy of68Ga-DOTATOC for several distinct indications and is intended to support approval of this agent by the U.S. Food and Drug Administration.Methods:The major electronic medical databases were searched for relevant papers over the period from January 2001 to November 2015. Papers were selected for review in 3 categories: clinical trials that reported sensitivity and specificity, comparison studies with111In-octreotide, and change of management studies. All the eligible papers underwent Quality Assessment of Diagnostic Accuracy Studies (QUADAS) assessment, which was useful in the final selection of papers for review.Results:The initial search yielded 468 papers. After detailed evaluation, 17 papers were finally selected. Five types of studies emerged: workup of patients with symptoms and biomarker findings suggestive of NET, but with negative conventional imaging (3 papers, yield was only 13%); sensitivity (12 papers; sensitivity, 92%) and specificity (7 papers; specificity, 82%); identification of site of unknown primary in patients with metastatic NET (4 papers, yield was 44%); impact on subsequent NET patient management (4 papers, change in management in 51%); and comparison with111In-octreotide (2 papers, sensitivity of DOTATOC on a per-lesion basis was 100%, for111In-octreotide it was 78.2%; specificity was not available). Safety was not explicitly addressed in any study, but there were no reports of adverse events.Conclusion:68Ga-DOTATOC is useful for evaluating the presence and extent in disease for staging and restaging and for assisting in treatment decision making for patients with NET. It is also effective in locating the site of an unknown primary in NET patients who present with metastatic NET, but no known primary tumor. It also appears to be more accurate than111In-octreotide. Although68Ga-DOTATOC would seem to be useful in evaluating patients with suggestive symptoms and biomarker findings, it does not perform well in this setting and has low yield. Overall, it appears to be an excellent imaging agent to assess patients with known NET and frequently leads to a change in management.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Iowa, Iowa City, Iowa michael-graham@uiowa.edu.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Graham
authors.affiliation: Hardin Library for the Health Sciences, University of Iowa, Iowa City, Iowa; and.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Gu
authors.affiliation: Holden Comprehensive Cancer Center, University of Iowa, Iowa City, Iowa.
authors.forename: Timothy
authors.initials: T
authors.lastname: Ginader
authors.affiliation: Holden Comprehensive Cancer Center, University of Iowa, Iowa City, Iowa.
authors.forename: Patrick
authors.initials: P
authors.lastname: Breheny
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Iowa, Iowa City, Iowa.
authors.forename: John J
authors.initials: JJ
authors.lastname: Sunderland
mesh_terms: D003952:Diagnostic Imaging / Q000379:methods*; D006801:Humans; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging*; D015282:Octreotide / Q000031:analogs & derivatives*; D009942:Organometallic Compounds; D012680:Sensitivity and Specificity
chemical_list: C499142:Ga(III)-DOTATOC; D009942:Organometallic Compounds; D015282:Octreotide
keywords: DOTATOC; metaanalysis; neuroendocrine; octreotide; pentetreotide; systematic review