Retrosternal Multinodular Goiter With Extensive Mediastinal Extension Requiring Combined Cervical Thyroidectomy and Median Sternotomy: A Case Report.

Retrosternal goiter is a distinct clinical entity, characterized by extension of thyroid tissue into the mediastinum, often increasing surgical complexity and necessitating individualized operative planning. We report a 55-year-old female patient presenting with a gradually enlarging anterior neck swelling without compressive or thyrotoxic symptoms. Clinical examination suggested mediastinal extension, and imaging with contrast-enhanced computed tomography confirmed a large multinodular goiter extending retrosternally up to the level of the D7 vertebra, abutting major mediastinal vessels without encasement. Fine-needle aspiration cytology was benign (Bethesda Category II). In view of the significant intrathoracic extension and proximity to vital structures, the patient underwent total thyroidectomy with a combined cervical approach and median sternotomy. Histopathological examination confirmed multinodular goiter without evidence of malignancy. The postoperative course was uneventful, and the patient remained asymptomatic on follow-up. This case highlights the importance of preoperative imaging in defining mediastinal extent and guiding surgical approach, emphasizing that extensive retrosternal extension and vascular proximity may necessitate a combined cervicothoracic approach to ensure safe and complete excision with minimal complications.