title: Clinical usefulness of ¹⁸F-fluorodeoxyglucose-positron emission tomography in patients with locally advanced pancreatic cancer planned to undergo concurrent chemoradiation therapy.
abstract: OBJECTIVE
  To assess the role of coregistered (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting radiographically occult distant metastasis (DM) at staging in patients with locally advanced pancreatic cancer (LAPC) and to study whether FDG-PET parameters can predict relatively long-term survival in patients who are more likely to benefit from chemoradiation therapy (CRT).
  
  
  METHODS
  From our institutional database, we identified 388 LAPC patients with M0 on conventional computed tomography (CT) who were planned to undergo CRT. Coregistered FDG-PET staging was offered to all patients, and follow-up FDG-PET was used at the clinical discretion of the physician.
  
  
  RESULTS
  FDG-PET detected unsuspected CT-occult DM in 33% of all 388 patients and allowed them to receive systemic therapy immediately. The remaining 260 patients (PET-M0) underwent CRT selectively as an initial treatment. Early DM arose in 13.1% of 260 patients, and the 1-year estimated locoregional recurrence rate was 5.4%. Median overall survival (OS) and progression-free survival (PFS) were 14.6 and 9.3 months, respectively, at a median follow-up time of 32.3 months (range, 10-99.1 months). Patients with a baseline standardized uptake value (SUV) <3.5 and/or SUV decline ≥60% had significantly better OS and PFS than those having none, even after adjustment for all potential confounding variables (all P<.001).
  
  
  CONCLUSIONS
  FDG-PET can detect radiographically occult DM at staging in one-third of patients and spare them from the potentially toxic therapy. Additionally, FDG-PET parameters including baseline SUV and SUV changes may serve as useful clinical markers for predicting the prognosis in LAPC patients.
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jee Suk
authors.initials: JS
authors.lastname: Chang
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seo Hee
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Youngin
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jeong Youp
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Si Young
authors.initials: SY
authors.lastname: Song
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Arthur
authors.initials: A
authors.lastname: Cho
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Mijin
authors.initials: M
authors.lastname: Yun
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jong Doo
authors.initials: JD
authors.lastname: Lee
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea. Electronic address: jsseong@yuhs.ac.
authors.forename: Jinsil
authors.initials: J
authors.lastname: Seong
mesh_terms: D000368:Aged; D059248:Chemoradiotherapy / Q000401:mortality; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000401:mortality; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18