title: Comparison of ⁶⁸Ga-DOTATATE PET-CT, ¹⁸F-FDG PET-CT and 99mTc-(V)DMSA scintigraphy in the detection of recurrent or metastatic medullary thyroid carcinoma.
abstract: OBJECTIVE
  We aimed to compare the efficacies of gallium-68 (68Ga) DOTATATE PET-computed tomography (CT), fluorine-18 fluorodeoxyglucose (18F-FDG) PET-CT and technetium-99m (99mTc)-(V)DMSA scintigraphy in the detection of residual/metastatic medullary thyroid carcinoma (MTC).
  
  
  METHODS
  We retrospectively evaluated DOTATATE PET-CT, 18F-FDG PET-CT and (V)DMSA scintigraphy of 22 MTC patients, all taken within a 6-month period in each patient, because of high levels of calcitonin (Ct) and carcinoembryonic antigen (CEA). We investigated the relationships between the results of the imaging modalities and tumour marker levels and the sporadic versus hereditary nature of the disease, as well as the effect of imaging results on patient management.
  
  
  RESULTS
  The ages of the patients at diagnosis were between 20 and 69 years. The median levels of Ct and CEA were 871.5 pg/ml and 11.2 ng/ml, respectively. In the patient-based analysis, we observed at least one focus of abnormal uptake in 15 of 22 DOTATATE PET-CT (68.2% sensitivity), eight of 18 18F-FDG PET-CT (44.4% sensitivity) and five of 15 (V)DMSA scans (33.3% sensitivity). These data showed a significant difference between DOTATATE PET-CT and (V)DMSA scintigraphy (P=0.016), whereas the relationships between DOTATATE PET-CT and 18F-FDG PET-CT and between 18F-FDG PET-CT and (V)DMSA scintigraphy showed no significant differences (P>0.05). In the lesion-based analysis, 134 lesions were detected with DOTATATE PET-CT, 76 lesions with 18F-FDG PET-CT and nine lesions with (V)DMSA scintigraphy.
  
  
  CONCLUSIONS
  DOTATATE PET-CT is an efficient imaging modality in MTC patients with increased Ct and CEA (especially >1000 pg/ml and 50 ng/ml, respectively) for localizing recurrent or metastatic disease. 18F-FDG PET-CT can be performed if DOTATATE PET-CT is not available, but (V)DMSA scintigraphy is not recommended.
authors.affiliation: Departments of aNuclear Medicine bInternal Medicine, Endocrinology and Metabolism Division cDepartment of Biostatistics and Medical Informatics, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Zeynep G
authors.initials: ZG
authors.lastname: Ozkan
authors.forename: Serkan
authors.initials: S
authors.lastname: Kuyumcu
authors.forename: Ayse Kubat
authors.initials: AK
authors.lastname: Uzum
authors.forename: Mehmet F
authors.initials: MF
authors.lastname: Gecer
authors.forename: Sevda
authors.initials: S
authors.lastname: Ozel
authors.forename: Ferihan
authors.initials: F
authors.lastname: Aral
authors.forename: Isik
authors.initials: I
authors.lastname: Adalet
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D018278:Carcinoma, Neuroendocrine; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009362:Neoplasm Metastasis; D018365:Neoplasm, Residual; D009942:Organometallic Compounds; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D009942:Organometallic Compounds; D019788:Fluorodeoxyglucose F18; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; C513399:gallium Ga 68 dotatate