title: Value of preoperative diagnostic modalities in patients with recurrent thyroid carcinoma.
abstract: BACKGROUND
  Patients with well-differentiated thyroid cancer (WDTC) regularly have an excellent prognosis. However, tumor recurrence either involving the thyroid bed or the regional lymph nodes, or both, can be associated with significant morbidity and even mortality. The aim of the follow-up after primary surgery is to detect recurrent disease at its earliest stage. We assessed the value of different diagnostic methods in detecting locoregional recurrence in patients with WDTC.
  
  
  METHODS
  We prospectively identified 150 patients with WDTC. Of those, 43 (28.7%) presented with recurrent disease. Ultrasonography-guided fine needle biopsy (US-FNB), iodine 131 ((131)I) wholebody scintigraphy, thyroglobulin (Tg) measurement, and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) were carried out.
  
  
  RESULTS
  Ultrasonography detected malignant lesions in 95.3% of the patients. The true positive rate of US-FNB was 95.3%. (131)I scanning had true positive, false negative, and false positive results in 54.2%, 40.0%, and 5.7% of the cases, respectively. In 85.7% of the patients, Tg levels were within pathologic range. Among the 13 patients who underwent FDG-PET, 84.6% showed pathologic uptake indicating malignancy. US and US-FNB provided the highest specificity for detecting recurrence (P <.001).
  
  
  CONCLUSIONS
  In patients with WDTC and locoregional recurrence, US and US-FNB are the most sensitive methods in detecting local recurrence or regional lymph node metastases. FDG-PET is valuable in case of negative (131)I scanning results and elevated serum Tg levels. The method has limitations in finding minimal disease.
authors: Department of General and Transplantation Surgery, University Hospital Essen, Essen, Germany.
authors: A
authors: A
authors: Frilling
authors: R
authors: R
authors: Görges
authors: K
authors: K
authors: Tecklenborg
authors: P
authors: P
authors: Gassmann
authors: M
authors: M
authors: Bockhorn
authors: M
authors: M
authors: Clausen
authors: C E
authors: CE
authors: Broelsch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D011379:Prognosis; D011446:Prospective Studies; D013954:Thyroglobulin / Q000097:blood; D013964:Thyroid Neoplasms / Q000175:diagnosis*; D014055:Tomography, Emission-Computed
chemical_list: D019788:Fluorodeoxyglucose F18; D013954:Thyroglobulin