Camouflaged Asymptomatic Mediastinal Thyroid Ectopia in a Patient with Toxic Goiter: A Case Report
Mohd Fazrin Mohd Rohani, Irfan Mohamad, Wan Mohd Nazlee Wan Zainon, Wan Faiziah Wan Abdul Rahman, Ahmad Adham Ali, Ahmad Zuhdi Mamat, Noorul Balqis Che Ibrahim, Aizat Sabri Ilias, Maya Mazuwin Yahya, Norazlina Mat Nawi
Citation Information :
Rohani MF, Mohamad I, Zainon WM, Rahman WF, Ali AA, Mamat AZ, Ibrahim NB, Ilias AS, Yahya MM, Nawi NM. Camouflaged Asymptomatic Mediastinal Thyroid Ectopia in a Patient with Toxic Goiter: A Case Report. World J Endoc Surg 2023; 15 (1):10-13.
Introduction: Ectopic mediastinal thyroid is uncommon, accounting for <1% of cases, and is often found incidentally on diagnostic imaging.
Case description: A 56-year-old female diagnosed with toxic multinodular goiter with incidental finding of a mediastinal mass during preoperative workup for total thyroidectomy. Differentials include enlarged metastatic lymph node, thymoma, ectopic parathyroid adenoma, ectopic thyroid tissue, dermoid cyst and lymphoma. A functional thyroid scan with technetium-99m (99mTc) pertechnetate was able to characterize the mediastinal mass as an ectopic thyroid tissue, obviating the need for an invasive presurgical biopsy. Subsequent total thyroidectomy and excision of the mediastinal mass later confirmed the presence of ectopic thyroid tissue in the mediastinum.
Conclusion: Although rare, mediastinal ectopic thyroid should be considered as one of the differentials in a mediastinal mass. 99mTc-pertechenetate SPECT/CT is a useful noninvasive tool to differentiate ectopic thyroid tissue from other mediastinal tumors and also assess its functional and anatomic characteristic. Surgical removal is advocated for treatment of mediastinal thyroid ectopia especially in symptomatic patients.
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