title: The clinical usefulness of 18-fluorodeoxyglucose positron emission tomography in the differential diagnosis, staging, and response evaluation after concurrent chemoradiotherapy for pancreatic cancer.
abstract: OBJECTIVE
  The aims of this study were to determine the clinical use of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the differential diagnosis of patients with suspected pancreatic cancer and in the determination of tumor response after concurrent chemoradiotherapy for pancreatic cancer.
  
  
  BACKGROUND
  Despite advances in diagnostic tools for pancreatic cancer, it is difficult to differentiate pancreatic cancer from mass-forming pancreatitis. Even with current imaging modalities, it is also difficult to assess tumor response to therapeutic intervention.
  
  
  METHODS
  One hundred two patients with suspected pancreatic cancer were selected for this study. Dynamic computerized tomography (CT) scan and FDG-PET were used sequentially to diagnose pancreatic cancer. After diagnostic confirmation their diagnostic yields were compared. We also evaluated the treatment response in 15 patients who underwent chemoradiation therapy with dynamic CT scan and FDG-PET and compared their results.
  
  
  RESULTS
  In 93 out of 102 patients, pancreatic cancer was confirmed. FDG-PET showed higher diagnostic accuracy than CT scan (95.1% vs. 76.5%). FDG-PET was also superior to CT in the detection of liver metastasis. FDG-PET detected treatment response in 5 out of 15 cases after chemoradiation therapy, whereas CT could not detect any treatment response. Comparing responder and nonresponder, FDG-PET was able to predict significantly different prognosis (399 vs. 233 d, P<0.05).
  
  
  CONCLUSIONS
  FDG-PET is a very useful tool in diagnosing pancreatic cancer. FDG-PET may be also used as an adjunct for determining the treatment modality of pancreatic cancer and evaluating tumor response to chemoradiation therapy.
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology, Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seungmin
authors.initials: S
authors.lastname: Bang
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Chung
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Jae Bock
authors.initials: JB
authors.lastname: Chung
authors.forename: Mijin
authors.initials: M
authors.lastname: Yun
authors.forename: Jong Doo
authors.initials: JD
authors.lastname: Lee
authors.forename: Si Young
authors.initials: SY
authors.lastname: Song
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000097:blood; D018395:CA-19-9 Antigen / Q000097:blood; D021441:Carcinoma, Pancreatic Ductal / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D050500:Pancreatitis, Chronic / Q000000981:diagnostic imaging / Q000473:pathology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D018714:Radiotherapy, Adjuvant; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18