title: Predictive value of 18F-FDG PET and somatostatin receptor scintigraphy in patients with metastatic endocrine tumors.
abstract: The treatment of metastatic neuroendocrine tumors depends on the aggressiveness of the disease. We wanted to know whether (18)F-FDG PET and somatostatin receptor scintigraphy (SRS) can predict early disease progression and patient survival.
  
  
  METHODS
  We undertook a prospective study of patients with metastatic neuroendocrine tumor diagnosed between September 2003 and January 2006. After obtaining signed informed consent from the patients, we performed CT, SRS, and (18)F-FDG PET and reviewed histologic data. CT was repeated every 3 mo to assess the risk of early progressive disease (first 6 mo), progression-free survival, and overall survival.
  
  
  RESULTS
  Thirty-eight patients (mean age, 60 +/- 15 y) were included. Histologically, 4 patients had a high-grade and 34 a low-grade tumor. The results of (18)F-FDG PET and SRS were positive in 15 and 27 patients. The 2-y overall survival and progression-free survival were 73% and 45%; 16 patients had early progressive disease. Most (18)F-FDG PET-positive patients had early progressive disease (14/15, vs. 2/23 (18)F-FDG PET-negative patients), and most SRS-negative patients had early progressive disease (9/11, vs. 7/27 SRS-positive patients); (18)F-FDG PET gave excellent negative and positive predictive values of 91% and 93%; (18)F-FDG PET results correlated with progression-free survival (P < 0.001) and overall survival (P < 0.001) even when only low-grade tumors were considered. SRS was associated with progression-free survival (P < 0.001) and overall survival (P < 0.03). At multivariate analysis, only (18)F-FDG PET was predictive of progression-free survival.
  
  
  CONCLUSIONS
  (18)F-FDG PET exhibits excellent predictive values for early tumor progression. (18)F-FDG PET and SRS results correlate with progression-free survival and overall survival even for histologically low-grade tumors. These explorations could be included in the initial work-up for metastatic neuroendocrine tumor.
authors.affiliation: UPRESS EA 3890 and Department of Medical Imaging, Centre E. Marquis, Rennes, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Garin
authors.forename: Florence
authors.initials: F
authors.lastname: Le Jeune
authors.forename: Anne
authors.initials: A
authors.lastname: Devillers
authors.forename: Marc
authors.initials: M
authors.lastname: Cuggia
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: de Lajarte-Thirouard
authors.forename: Catherine
authors.initials: C
authors.lastname: Bouriel
authors.forename: Eveline
authors.initials: E
authors.lastname: Boucher
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Raoul
mesh_terms: D000328:Adult; D000368:Aged; D018450:Disease Progression; D004701:Endocrine Gland Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007205:Indium Radioisotopes; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin / Q000032:analysis*; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; D019788:Fluorodeoxyglucose F18; D013004:Somatostatin; C081788:pentetreotide