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False-positive I-131 Uptakes at Pulmonary Wedge-resection Site and Soft Tissue Lateral to the Femoral Heads in a Patient with Papillary Thyroid Carcinoma

10.4274/mirt.galenos.2018.09821

  • Bülent Yazıcı
  • Aylin Oral
  • Şeyma Alçiçek
  • İpek Tamsel
  • Ayşegül Akgün

Received Date: 01.06.2018 Accepted Date: 07.09.2018 Mol Imaging Radionucl Ther 2019;28(1):34-37

A hyper-metabolic pulmonary nodule was detected on 18F-FDG PET/CT in a 65-year-old woman who had been followed up for 12 years without any complaints following treatment for papillary thyroid cancer (PTC). Wedge resection was performed to the pulmonary nodule and the pathologic examination revealed PTC metastasis. On the post-therapeutic I-131 scan after radioiodine treatment, focal I-131 uptake was detected at the site of pulmonary wedge resection. At first, this finding was thought to be related to the residual lesion but diagnostic CT demonstrated only focal traction bronchiectasis at that region. In addition, a false-positive I-131 uptake was also detected at the soft tissue just lateral to the femoral heads probably due to inflammation.

Keywords: Thyroid, cancer, false-positive, iodine, I-131

Ethics

Informed Consent: Consent form was filled out by all participants.

Peer-review: Externally peer-reviewed.

Authorship Contributions

Medical Practices: B.Y., A.O., Ş.A., İ.T., A.A., Concept: B.Y., A.O., Ş.A., Design: B.Y., A.O., Ş.A., Data Collection or Processing: B.Y., Analysis or Interpretation: B.Y., A.O., İ.T., A.A., Literature Search: B.Y., Ş.A., Writing: B.Y.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.

Images

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