title: Bronchogenic carcinoid tumours that are 18F-fluorodeoxyglucose avid on positron emission tomography.
abstract: OBJECTIVE
  Bronchogenic carcinoid tumours are widely cited as non-fluorodeoxyglucose (FDG) avid. However, three case reports of FDG-avid bronchogenic carcinoid tumours have been published, leading to speculation as to which clinicopathological factors may be associated with increased activity on FDG-positron emission tomography. We reviewed a series of cases from our institution and compared them with the available reports in the literature, to attempt to identify the factors associated with FDG avidity in bronchogenic carcinoids.
  
  
  METHODS
  We performed a single-institution retrospective review.
  
  
  RESULTS
  One patient was identified at our institution who had a typical carcinoid tumour with a standardized uptake value (SUV) of 26, oncocytic features on histology and positive staining for glucose transporter 1 (GLUT1). Three additional patients were identified in the literature with typical bronchogenic carcinoids with SUVs of 39, 38 and 33. Two of these tumours stained positive for GLUT1, and the remaining patient was not tested. Two of these patients had oncocytic features on histology, and results on the remaining patient are not reported. Additionally, 4 patients at our institution were identified with bronchogenic carcinoids with average SUV of 2.6. All were GLUT1 negative, and none had oncocytic features. In the reported literature, excluding the four most FDG-avid tumours described above, atypical carcinoids had a higher mean SUV than typical carcinoids (5.7 vs 3.4, P = 0.02), but size was not correlated with SUV (r = 0.7, P = 0.3).
  
  
  CONCLUSIONS
  FDG uptake is commonly associated with worse prognosis in malignancy; however, bronchogenic carcinoids, particularly oncocytic typical carcinoids, are a possible source of extremely high SUVs on FDG-PET.
authors.affiliation: Swedish Medical Center and Cancer Institute, Seattle, WA, USA.
authors.forename: Ben M
authors.initials: BM
authors.lastname: Hunt
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Horton
authors.forename: Eric
authors.initials: E
authors.lastname: Vallières
mesh_terms: D002276:Carcinoid Tumor / Q000737:chemistry / Q000000981:diagnostic imaging* / Q000378:metabolism; D002283:Carcinoma, Bronchogenic / Q000737:chemistry / Q000000981:diagnostic imaging* / Q000378:metabolism; D019788:Fluorodeoxyglucose F18; D051272:Glucose Transporter Type 1 / Q000032:analysis / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods; D012189:Retrospective Studies
chemical_list: D051272:Glucose Transporter Type 1; D019788:Fluorodeoxyglucose F18
keywords: Bronchogenic carcinoid; FDG-PET; GLUT1; Oncocytic