title: Diagnostic value of FDG PET and salivary gland scintigraphy for parotid tumors.
abstract: OBJECTIVE
  The purpose of this study was to examine the diagnostic value of the combination of F-18 fluorodeoxyglucose (FDG) PET and Tc-99m pertechnetate salivary gland scintigraphy in parotid tumors.
  
  
  METHODS
  Seventy-two patients with benign parotid gland tumors (n = 52), malignant parotid tumors (n = 12), and inflammation (n = 8) underwent both FDG PET and salivary gland scintigraphy within 1 week, and 66 of the patients also underwent gallium scintigraphy. All patients were negative on their first fine-needle aspiration (FNA).
  
  
  RESULTS
  Malignant parotid tumors showed significantly higher FDG uptake (standard uptake values [SUVs]) than both benign tumors and inflammation, except in Warthin's tumor (5.82 +/- 3.95 vs. 2.07 +/- 1.33; P <0.01). Although the SUV values of Warthin's tumor and malignant parotid tumors overlapped somewhat, Warthin's tumor did demonstrate increased radiotracer uptake, and it was reliably distinguished from other parotid gland tumors by the use of salivary gland scintigraphy. Considering a SUV value >3 as being positive for malignancy and excluding Warthin's tumor on the basis of salivary gland scintigraphy, sensitivity and specificity of FDG PET were 75% and 80%, respectively. These results were superior to those of gallium scintigraphy (58% and 72%, respectively).
  
  
  CONCLUSIONS
  Although the diagnostic value of FDG PET in the differentiation of malignant from benign parotid gland tumors was limited because of the high FDG uptake in some benign tumors, and particularly pleomorphic adenomas, combining salivary gland scintigraphy with FDG PET may help to negate this drawback, and this combination may be a more promising approach for differentiation of various parotid gland tumors in patients compared with nondiagnostic needle aspiration.
authors.affiliation: Department of Radiology, Chiba University School of Medicine, Chiba, Japan. uchiday@faculty.chiba-u.jp
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Uchida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Minoshima
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kawata
authors.forename: Ken
authors.initials: K
authors.lastname: Motoori
authors.forename: Koichi
authors.initials: K
authors.lastname: Nakano
authors.forename: Toshiki
authors.initials: T
authors.lastname: Kazama
authors.forename: Takashi
authors.initials: T
authors.lastname: Uno
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Hisao
authors.initials: H
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18