The ectopic thyroid gland is rare and can be found anywhere from the tongue to the diaphragm. Mediastinal ectopic thyroid is extremely rare (1% of mediastinal tumors), most commonly in the anterior mediastinum, and patients are usually euthyroid and asymptomatic. However, dyspnea, dysphagia, or superior vena cava syndrome are possible clinical presentations. Although a potential for malignant transformation exists in the ectopic thyroid, it is a rarity, with only five cases reported. As in the orthotopic thyroid, papillary carcinoma is the most frequent cancer found. Scintigraphy is the most valuable diagnostic tool, but Doppler US, CT scan, or MRI can help surgery planning (exact location, relationships with adjacent structures).
It is essential to differentiate the ectopic thyroid from the substernal extension of a cervical gland. Ectopic thyroid has no connection with the cervical gland and has an independent vascular supply from the intrathoracic vessels. The substernal extension is not uncommon and represents a growth of the cervical thyroid into the thorax. It has implications for the treatment since the substernal thyroid usually does not need a thoracic approach.
General Surgeons and Thoracic Surgeons from the Portuguese Oncology Institute of Coimbra (IPO Coimbra), Portugal, worked together to treat and publish in the International Journal of Surgery Case Reports (May 2023) the sixth case of mediastinal ectopic thyroid cancer. A male patient submitted to an uneventful total thyroidectomy (8 synchronous papillary carcinomas) was sent to IPO Coimbra because of persistent elevation of thyroglobulin. A mediastinal mass with 6x3 cm was diagnosed as being ectopic thyroid. According to Dr. Teresa Caroço et al., “no FNAC of the mediastinal mass was performed since surgical approach was immediately decided”. After a multidisciplinary discussion (Endocrinologist, Radiologist, General Surgeon, and Thoracic Surgeon) a Video-Assisted Thoracic Surgery (VATS) was conducted without complications (Dr. Ana Luis Garcia and Dr. Tiago Nogueira). The authors used three trocars, a 30º camera, and a LigaSure Maryland Thoracic Sealer®. The postoperative period was uneventful, and the patient was discharged home two days after. One month later the patient was doing fine, with thyroglobulin within normal range. Pathology concluded for hyperplasic nodules and papillary carcinoma (T1a). This was the first worldwide report of a mediastinal ectopic thyroid cancer treated by VATS.
As the authors' state, surgical resection is the only curative treatment. Nowadays, VATS is the best option with several advantages over open techniques. VATS allows for better visualization, has less morbidity and less mortality, and promotes faster recovery with less pain. Tumor size is the only limit. Want to know what it is? Read the paper for that and other precious information.
A multidisciplinary approach is constant in the Portuguese Oncology Institute of Coimbra (IPO Coimbra). This way of working promotes a productive discussion by converging ideas from different areas of medicine, making it possible to offer the patient the best treatment strategy. This is the way!
Do you enjoy adrenal surgery? Must have this new book!
Costa Almeida CE, editor. Posterior Retroperitoneoscopic Adrenalectomy. Indications, Technical Steps and Outcomes. Switzerland: Springer; 2023.
Link to article:
Dr. Carlos Eduardo Costa Almeida
General Surgeon