title: Usefulness of fluoro-2-deoxyglucose positron emission tomography for investigating unexplained rising carcinoembryonic antigen levels that occur during the postoperative surveillance of lung cancer patients.
abstract: BACKGROUND
  Positron emission tomography with 18-fluorodeoxyglucose (FDG-PET) has been useful for the detection of recurrent lung cancer. However, such technology is expensive and is not always widely available. In this study, we evaluated the selected use of FDG-PET for lung cancer patients with re-elevated levels of serum carcinoembryonic antigen (CEA) after curative surgery.
  
  
  METHODS
  Among 327 patients who underwent curative resection for primary lung cancer from May 2002 through March 2007, 199 had adenocarcinoma, of whom 78 (39%) had elevated levels of serum CEA before treatment. After surgery, the level was monitored every 1 to 3 months. Re-elevation of CEA was recognized in 39 (50%) patients, 22 of whom underwent FDG-PET and were included in this study. FDG-PET images were visually inspected, and abnormally increased FDG uptake was interpreted as recurrence. The sensitivity, specificity, positive predictive value, and negative predictive value of PET in detecting recurrent lung cancer were determined.
  
  
  RESULTS
  FDG-PET correctly identified 14 out of 15 relapses and gave true negative results in six out of seven remissions, i.e., one false-negative and one false-positive were observed. The sensitivity, specificity, positive predictive value, and negative predictive value were 93%, 86%, 93%, and 86%, respectively.
  
  
  CONCLUSIONS
  In 64% of the patients with unexplained increased CEA levels, FDG-PET provided decisive diagnostic clues guiding further diagnostic and therapeutic interventions. The selected use of FDG-PET for patients with re-elevated serum CEA levels after surgery can be a practical and effective mode of surveillance for detecting recurrent lung cancer.
authors.affiliation: Department of Respiratory Medicine, Toho University Omori Medical Center, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan. kazutoshiisobe@aol.com
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Isobe
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Hata
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Takai
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Shibuya
authors.forename: Keigo
authors.initials: K
authors.lastname: Takagi
authors.forename: Sakae
authors.initials: S
authors.lastname: Homma
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002272:Carcinoembryonic Antigen / Q000097:blood*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011184:Postoperative Period; D019275:Radiopharmaceuticals
chemical_list: D002272:Carcinoembryonic Antigen; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18