A rare clinical case of malignant ectopic retrosternal goiter of a large size in a patient with aberrant right subclavian artery

Background. Ectopic goiter accounts for only 0.2 % to 1 % of all mediastinal goiters. The aberrant right subclavian artery (arteria lusoria) is an extremely rare anomaly of the major vessel, with a prevalence not exceeding 0.3 % in the general population. This paper presents the first case of malignant ectopic retrosternal goiter of a large size in combination with the aberrant right subclavian artery. Clinical Case Description. A 61-year-old male presented to the Thoracic Surgery Department of P. Herzen Moscow Oncology Research Institute with a large posterior mediastinal mass measuring 108×106×79 mm and adjacent to the right lobe of the thyroid gland. The tumor displaced the trachea and esophagus. Open biopsy through a thoracotomy incision revealed thyroid gland cells without signs of atypia. A detailed examination revealed mediastinal vascular anomaly - retrotracheal position of the right subclavian artery. A complete longitudinal sternotomy, complemented by a right-sided thoracotomy at the 3rd intercostal space, served as the surgical approach. The operation lasted 320 minutes, with a blood loss of 3500 ml. The postoperative period was uneventful. The morphological examination of the surgical specimen revealed nodular hyperplasia of the ectopic thyroid tissue with the growth of well-differentiated follicular carcinoma without metastatic involvement of removed lymph nodes. Considering the identified follicular carcinoma, total thyroidectomy was performed.