title: Columnar cell thyroid carcinoma - diagnostic dilemmas and pitfalls.
abstract: BACKGROUND
  Columnar cell carcinoma is a rare variant of papillary thyroid carcinoma associated with aggressive clinical behaviour.
  
  
  METHODS
  of a 34-year-old male patient, who presented with the rapidly growing mass in the neck, extending to the anterior and middle mediastinum, tightly closing the upper thoracic apperture and causing tracheal and oesophageal deviation, with minimal compression and stenosis. A diagnosis of columnar cell carcinoma, arising from the ectopic thyroid tissue just adjacent to the left thyroid lobe was based on histological and intraoperative findings. Near total thyroidectomy and lymph-node dissection were followed by external beam radiotherapy of the neck and mediastinum, chemotherapy and radioiodine ablation of the remaining functional thyroid tissue. Pre-and post-operative radionuclide imaging (99mTc(V)-DMSA, 99mTc-MIBI, 123-I-mIBG and Octreoscan findings are discussed, with a special emphasis given to the dilemmas in histological characterisation of the tumor, the problems in therapeutic approach and the dilemmas and pitfalls in the interpretation of radionuclide findings in this patient, especially the ones performed post radiotherapy of the neck and mediastinum.
authors.affiliation: Department of Nuclear Medicine, Institute of Oncology, Ljubljana, Slovenia. izagar@onko-i.si
authors.forename: Ivana
authors.initials: I
authors.lastname: Zagar
authors.forename: Barbara
authors.initials: B
authors.lastname: Vidergar-Kralj
authors.forename: Andreja A
authors.initials: AA
authors.lastname: Schwarzbartl-Pevec
authors.forename: Franc
authors.initials: F
authors.lastname: Pompe
mesh_terms: D000328:Adult; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000556:secondary / Q000628:therapy; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D006801:Humans; D008297:Male; D011877:Radionuclide Imaging; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000628:therapy