title: The role of 18F-FDG PET/CT in the evaluation of gastric cancer recurrence after curative gastrectomy.
abstract: OBJECTIVE
  (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) scans are frequently performed for the screening or staging of malignant tumors. This study aimed to assess the usefulness of (18)F-FDG PET/CT in detection of gastric cancer recurrence after curative gastrectomy.
  
  
  METHODS
  Eighty nine patients who had undergone curative gastrectomy due to gastric cancer and had (18)F-FDG PET/CT and contrast CT scans within 2 weeks for surveillance in asymptomatic patients (n = 11) or to clarify suspected recurrence (n = 78) were consecutively collected and retrospectively analyzed. They had clinical follow-up for at least 12 months after PET/CT and CT scans.
  
  
  RESULTS
  Fifteen of the 89 patients (16.9%) were diagnosed with recurrent gastric cancer in 21 organs. Forty one organs showed an increase in FDG uptake, and only 9 of these organs were diagnosed with recurrent gastric cancer by (18)F-FDG PET/CT. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the (18)F-FDG PET/CT were 42.9%, 59.7%, 29.3%, 78.2%, and 57.3%, respectively. On the CT scan, 18 of 21 recurrent gastric cancers were detected, and 7 cases were in agreement with the (18)F-FDG PET/CT. The sensitivity and specificity of the CT scan were 85.8% and 87.3%, respectively, which are superior to the (18)F-FDG PET/CT. When we diagnosed a recurrence based on either (18)F-FDG PET/CT or CT scans, the sensitivity increased to 95.2% and the specificity decreased to 45.6%, when compared with the contrast CT scan alone.
  
  
  CONCLUSIONS
  (18)F-FDG PET/CT is an insufficient diagnostic method in detection of recurrence after curative gastrectomy, and even less accurate than contrast CT scan alone.
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Sung Pyo
authors.initials: SP
authors.lastname: Hong
authors.forename: Dae Ho
authors.initials: DH
authors.lastname: Ahn
authors.forename: Tae Joo
authors.initials: TJ
authors.lastname: Jeon
authors.forename: Min Kyung
authors.initials: MK
authors.lastname: Kang
authors.forename: Chang Il
authors.initials: CI
authors.lastname: Kwon
authors.forename: Kwang Hyun
authors.initials: KH
authors.lastname: Ko
authors.forename: Seong Gyu
authors.initials: SG
authors.lastname: Hwang
authors.forename: Pil Won
authors.initials: PW
authors.lastname: Park
authors.forename: Kyu Sung
authors.initials: KS
authors.lastname: Rim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D005743:Gastrectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D049268:Positron-Emission Tomography / Q000379:methods*; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019788:Fluorodeoxyglucose F18