title: Underperformance of gallium-67 scan is greater in relapse than in initial staging, compared with FDG PET.
abstract: OBJECTIVE
  The purpose of this study is to evaluate the performance of gallium-67 scan (GS) and F-18 fluorodeoxyglucose (FDG) PET scan in lymphoma staging and recurrence detection by comparing the 2 imaging studies in the same patient.
  
  
  METHODS
  A total of 42 patients from the period between July 2002 and May 2006 were included in this study. Of the 42 patients, 6 had Hodgkin disease and 36 had non-Hodgkin lymphomas. All of them underwent one or more FDG PET scans and also underwent corresponding GS performed within 7 days of FDG PET, for staging or detection of lymphoma recurrence. Among the non-Hodgkin lymphoma cases, 18 were diffuse large B-cell lymphoma, 10 were follicular center cell lymphoma, and 8 were of other types. Of the total 46 pairs of imaging performed in these 42 patients, 27 were for staging, and 19 for restaging after recurrence.
  
  
  RESULTS
  In all these studies, FDG PET detected 230 lesion sites, whereas GS detected 85 lesion sites. All of the lesions detected by GS were noted on FDG PET, whereas GS detected only 37.0% of the lesions detected by FDG PET. Among the 27 studies for staging, FDG PET detected 120 lesions, whereas GS detected 68 lesions (56.7%). In the 19 images taken for relapse, FDG PET detected 110 lesions, whereas GS detected only 17 (15.5%).
  
  
  CONCLUSIONS
  FDG PET is superior to GS in staging and detecting all types of lymphoma. The difference is notably more significant in recurrence detection.
authors: Department of Nuclear Medicine, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan. yuyi@kfsyscc.org
authors: Yu-Yi
authors: YY
authors: Huang
authors: Dong-Ling
authors: DL
authors: You
authors: Mei-Ching
authors: MC
authors: Liu
authors: Tran-Der
authors: TD
authors: Tan
authors: Pei-Ing
authors: PI
authors: Lee
authors: Ming-Yuan
authors: MY
authors: Lee
mesh_terms: D005260:Female; D019788:Fluorodeoxyglucose F18; D005710:Gallium Radioisotopes; D006801:Humans; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D012008:Recurrence; D051598:Whole Body Imaging
chemical_list: D005710:Gallium Radioisotopes; D019788:Fluorodeoxyglucose F18