Zeynep Gozde Ozkan1, Yasemin Sanli1, Berker Ozkan2, Artur Salmaslioglu3, Ferihan Aral4, Seher Nilgun Unal1

Keywords: Differentiated thyroid carcinoma, thyroglobulin, radioactive iodine treatment, mediastinal thyroid tissue


Thyroglobulin (Tg) which is used as a tumor marker in differentiated thyroid carcinoma (DTC) patients can be secreted from benign tissues, along with malignant tissues due to DTC. We present a young female patient with papillary microcarcinoma of thyroid who, after total thyroidectomy, had unexpectedly high level of Tg. After diagnostic work out, the source of Tg came out to be thyroid tissue, located in mediastinum instead of a malignant focus. After resection of this tissue, Tg level diminished which led to the decision of omitting radioactive iodine (RAI) treatment which would be an unnecessary treatment option for this patient.