title: 18F-FDG PET/CT rarely provides additional information other than primary tumor detection in patients with pulmonary carcinoid tumors.
abstract: OBJECTIVE
  The purpose of this study was to assess the contribution of (18)F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET)/Computed Tomography (CT) in detection and staging of pulmonary carcinoid tumors.
  
  
  METHODS
  A total of 22 patients with pulmonary carcinoid tumors (14 typical, 8 atypical) were reviewed in this retrospective study. PET/CT images of all patients were evaluated for primary tumor as well as metastatic regional lymph nodes, bone and other distant metastases. PET/CT positivity of primary tumors was determined by visual interpretation. Tumor size, SUVmax and Hounsfield Unit (HU) values of the tumors were used to test for differences between tumor groups (typical carcinoids and atypical carcinoids).
  
  
  RESULTS
  SUVmax of carcinoids ranged from 1.24 to 11.1 (mean, 5.0; median, 2.67). The mean largest diameter of primary tumors was 2.7 ± 1.3 cm, ranging from 1 to 5.5 cm. The overall sensitivity of FDG PET/CT for detection of pulmonary carcinoid tumors was 81.8%. Tumor size, SUVmax and Hounsfield Unit (HU) values of the atypical carcinoids were higher than those for typical carcinoids. However, the results were not statistically meaningful (P > 0.05). The sensitivity and specificity of FDG PET/CT in the detection of mediastinal and hilar lymph nodes metastases were 25% and 83% respectively. One patient had bone metastasis.
  
  
  CONCLUSIONS
  Although FDG PET/CT can be a useful tool for the detection of pulmonary carcinoid tumors and distant metastasis, it cannot discriminate typical carcinoids from atypical ones and absence of an FDG avid lesion cannot exclude pulmonary carcinoid tumors. Moreover, PET/CT is not a reliable tool in the staging of mediastinal and hilar lymph nodes especially for those patients with typical carcinoids.
authors.affiliation: Department of Nuclear Medicine, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Ebru
authors.initials: E
authors.lastname: Tatci
authors.affiliation: Department of Nuclear Medicine, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Ozlem
authors.initials: O
authors.lastname: Ozmen
authors.affiliation: Department of Radiology, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Atila
authors.initials: A
authors.lastname: Gokcek
authors.affiliation: Department of Nuclear Medicine, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Inci Uslu
authors.initials: IU
authors.lastname: Biner
authors.affiliation: Department of Pathology, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Esra
authors.initials: E
authors.lastname: Ozaydin
authors.affiliation: Department of Thoracic Surgery, Ataturk Chest Diseases and Thoracic Surgery Training and Research Hospital, Ankara, Turkey.
authors.forename: Sadi
authors.initials: S
authors.lastname: Kaya
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy and Medical Faculty, Ankara, Turkey.
authors.forename: Nuri
authors.initials: N
authors.lastname: Arslan
keywords: FDG PET/CT; pulmonary carcinoid tumor; synchronous pulmonary carcinoids