title: Detection of thyroid carcinoma in wall of a cystic lesion by FDG PET.
abstract: OBJECTIVE
  Three cases are described, in which positron emission tomography (PET) led to the diagnosis of carcinoma in solitary thyroid nodules (STN), which were considered benign by clinical assessment, ultrasonography, and fine needle aspiration cytology (FNAC).
  
  
  METHODS
  These 3 cases were from a group of 51 patients with solitary thyroid nodules that were nonfunctioning or "cold" on pertechnetate scans that were later studied with FDG PET scanning.
  
  
  RESULTS
  Of the entire group, 28 patients showed the nodule to be nonfunctioning on FDG scans. Of these, 3 showed one or more small foci of intense FDG uptake in the periphery. On histopathology, these sites were found to harbor carcinoma, papillary carcinoma in 2 patients and a follicular variant of papillary carcinoma in one.
  
  
  CONCLUSIONS
  These cases demonstrate the usefulness of FDG PET in detection of cancer that may lurk in the wall of a cystic thyroid nodule, often misinterpreted as benign by conventional methods.
authors.affiliation: Radiation Medicine Centre, Tata Memorial Hospital, Mumbai, India.
authors.forename: Narendra
authors.initials: N
authors.lastname: Nair
authors.forename: Archi
authors.initials: A
authors.lastname: Agrawal
authors.forename: U N
authors.initials: UN
authors.lastname: Nayak
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging*; D003560:Cysts / Q000175:diagnosis / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000175:diagnosis / Q000000981:diagnostic imaging*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18