title: 68Ga-DOTANOC PET/CT for baseline evaluation of patients with head and neck paraganglioma.
abstract: The purpose of this study was to evaluate the role of (68)Ga-labeled DOTANOC PET/CT for baseline evaluation of patients with head and neck paragangliomas (HNPs).
  
  
  METHODS
  The data for 26 patients (mean age ± SD, 34.3 ± 10.4 y; 50% men) with known or suspected HNPs who underwent (68)Ga-DOTANOC PET/CT for staging were retrospectively analyzed. PET/CT was performed after intravenous injection of 132-222 MBq of (68)Ga-DOTANOC. The images were evaluated by 2 experienced nuclear medicine physicians in consensus, both qualitatively and quantitatively. The PET/CT findings were grouped as HNPs, paraganglioma at other sites (non-HNPs), and metastatic disease. The size and maximum standardized uptake values (SUVmax) were measured for all lesions. All of the patients also underwent whole-body (131)I-metaiodobenzylgunanidine ((131)I-MIBG) scintigraphy and conventional imaging (CT/MR imaging) of the head and neck region. Their results were compared with those of (68)Ga-DOTANOC PET/CT.
  
  
  RESULTS
  (68)Ga-DOTANOC PET/CT findings were positive in all 26 patients, and 78 lesions were detected. PET/CT imaging demonstrated 45 HNPS, 10 non-HNPs, and 23 metastatic sites. Fifteen patients (57.6%) had more than one site of disease on PET/CT. Among 45 HNPs, 26 were carotid body tumors (CBTs), 15 glomus jugulare, 3 glomus tympanicum, and 1 laryngeal paraganglioma. A positive correlation was seen between size and SUVmax of HNPs (ρ = 0.323; P = 0.030). The SUVmax of the CBTs was higher than that of jugulotympanic paragangliomas (P = 0.026). No correlation was seen between size and SUVmax (ρ = 0.069; P = 0.854) of non-HNPs. The size and SUVmax of non-HNPs were significantly less than those of HNPs (P = 0.029 and 0.047, respectively). (131)I-MIBG scintigraphy showed only 30 of the 78 lesions and was inferior to PET/CT (P < 0.0001). Conventional imaging (CT/MR imaging) was positive for 42 of 49 head and neck lesions and was inferior to PET/CT on direct comparison (P = 0.015). A combination of CT/MR imaging and (131)I-MIBG scintigraphy detected only 53 of 78 (67.9%) lesions and was also inferior to PET/CT (P < 0.0001).
  
  
  CONCLUSIONS
  (68)Ga-DOTANOC PET/CT is useful for the baseline evaluation of patients with HNPs and can demonstrate synchronous paragangliomas at other sites and distant metastases. It is superior to (131)I-MIBG scintigraphy and conventional imaging (CT/MR imaging) for this purpose.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Punit
authors.initials: P
authors.lastname: Sharma
authors.forename: Alok
authors.initials: A
authors.lastname: Thakar
authors.forename: Sudhir
authors.initials: S
authors.lastname: Suman K C
authors.forename: Varun Singh
authors.initials: VS
authors.lastname: Dhull
authors.forename: Harmandeep
authors.initials: H
authors.lastname: Singh
authors.forename: Niraj
authors.initials: N
authors.lastname: Naswa
authors.forename: Rama Mohan
authors.initials: RM
authors.lastname: Reddy
authors.forename: Sellam
authors.initials: S
authors.lastname: Karunanithi
authors.forename: Rajeev
authors.initials: R
authors.lastname: Kumar
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kumar
authors.forename: Arun
authors.initials: A
authors.lastname: Malhotra
authors.forename: Chandrasekhar
authors.initials: C
authors.lastname: Bal
mesh_terms: D019797:3-Iodobenzylguanidine; D000293:Adolescent; D000328:Adult; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009942:Organometallic Compounds; D010235:Paraganglioma / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: C504894:68Ga-DOTANOC; D009942:Organometallic Compounds; D019797:3-Iodobenzylguanidine
keywords: 131I-MIBG; 68Ga-DOTANOC; PET/CT; head and neck paraganglioma; staging