title: [Value of (18)F-FDG dual head coincidence imaging in predicting the efficacy of radioiodine therapy for papillary thyroid carcinoma with cervical lymph node metastasis].
abstract: OBJECTIVE
  To assess the value of (18)F-FDG dual head coincidence imaging in the prediction of the efficacy of radioiodine therapy in patients with cervical lymph node (LN) metastasis of papillary thyroid carcinoma (PTC).
  
  
  METHODS
  Thirty-six patients undergoing thyroidectomy and radioiodine ablation of the residual normal thyroid tissue received (18)F-FDG dual head coincidence imaging and then therapeutic (131)I-whole body imaging ((131)I-WBI) in the same week. According to those imaging results, the patients were divided into group I with positive results of both imaging examinations and group II with positive results by (131)I-WBI but negative results by(18)F-FDG dual head coincidence imaging. All the patients were followed up for 6 months.
  
  
  RESULTS
  In group I (14 patients), a total of 49 lesions were diagnosed as cervical LN metastases, and the total sensitivity differed significantly between (18)F-FDG dual head coincidence imaging and (131)I- WBI (67.3% vs 89.8%, P=0.027). In both groups, the total sensitivity of (18)F-FDG dual head coincidence imaging and (131)I-WBI showed a significant difference (26.0% vs 94.5%, P<0.001). The target and non-target ratio (T/NT) was identified as one of the factors affecting the radioiodine efficacy (P<0.001). In group II (22 patients), 76 lesions were diagnosed as cervical LN metastases. The effective rates of groups I and II were 35.7% and 81.8%,  respectively, showing a significant difference between them (P=0.011).
  
  
  CONCLUSIONS
  (131)I-WBI is more sensitive than (18)F-FDG dual head coincidence imaging in detecting cervical LN metastasis in patients with PTC. Patients with cervical LN metastases who have positive results in both (131)I-WBI and (18)F-FDG dual head coincidence imaging tend to have a poorer response to the therapy than the patients with negative results in (18)F-FDG dual head coincidence imaging. The T/NT of the cervical LN metastases in (18)F-FDG dual head coincidence imaging is associated with the efficacy of radioiodine therapy.
authors.affiliation: Department of Nuclear Medicine, Southern Medical University, Guangzhou, China. yungangsun@sina.com
authors.forename: Yun-gang
authors.initials: YG
authors.lastname: Sun
authors.forename: Hui-juan
authors.initials: HJ
authors.lastname: Feng
authors.forename: Jin-hua
authors.initials: JH
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Hu
authors.forename: Wei
authors.initials: W
authors.lastname: Ouyang
mesh_terms: D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D002291:Carcinoma, Papillary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008297:Male; D009333:Neck / Q000000981:diagnostic imaging / Q000473:pathology; D011877:Radionuclide Imaging; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D016896:Treatment Outcome; D051598:Whole Body Imaging
chemical_list: D007457:Iodine Radioisotopes; D019788:Fluorodeoxyglucose F18