title: Preliminary study of 11C-choline PET/CT for T staging of locally advanced nasopharyngeal carcinoma: comparison with 18F-FDG PET/CT.
abstract: Evaluation of nasopharyngeal carcinoma (NPC) using (18)F-FDG PET/CT is limited by the intense physiologic uptake of (18)F-FDG in the brain. We attempted to improve detection of intracranial tumor invasion (including better delineation of invasion near the skull base) in locally advanced NPC using(11)C-choline PET/CT.
  
  
  METHODS
  Fifteen patients with newly diagnosed or recurrent locally advanced NPC were enrolled in the study. (18)F-FDG and (11)C-choline PET/CT was performed on all patients. PET/CT images obtained using the 2 tracers were compared using both maximum standardized uptake value (SUVmax) and tumor-to-brain (T/B) ratios. All patients were followed up for more than 1 y.
  
  
  RESULTS
  The sensitivity of (18)F-FDG PET/CT in detecting locally advanced NPC was 86.6%, compared with a 100% sensitivity for (11)C-choline PET/CT (t = 2.143, P = 0.483). The SUVmax of lesions detected was higher using (18)F-FDG than using (11)C-choline (12.81 ± 5.00 vs. 6.84 ± 2.76, t = 6.416, P < 0.001), but the T/B ratio was much higher for (11)C-choline than for (18)F-FDG (18.62 ± 7.95 vs. 1.38 ± 0.59, t = 8.801, P < 0.001). Compared with (18)F-FDG PET/CT, (11)C-choline PET/CT improved the delineation of intracranial invasion in 6 of 12 patients (χ(2) = 8.00, P = 0.014), skull base invasion in 4 of 14 patients, and orbital invasion in 3 of 3 patients.
  
  
  CONCLUSIONS
  (11)C-choline can improve the quality of PET/CT in the T staging of NPC.
authors.affiliation: Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Hu-bing
authors.initials: HB
authors.lastname: Wu
authors.forename: Quan-shi
authors.initials: QS
authors.lastname: Wang
authors.forename: Ming-fang
authors.initials: MF
authors.lastname: Wang
authors.forename: Xiaokang
authors.initials: X
authors.lastname: Zhen
authors.forename: Wen-lan
authors.initials: WL
authors.lastname: Zhou
authors.forename: Hong-sheng
authors.initials: HS
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D002250:Carbon Radioisotopes; D002794:Choline; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging; D009367:Neoplasm Staging / Q000379:methods*; D010865:Pilot Projects; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D002794:Choline