Robot-assisted Resection of an Infected Thymic Cyst: A Case Report

Abstract

Thymic cysts are rare benign lesions of the mediastinum that are often asymptomatic and incidentally discovered. However, infection can lead to inflammation, wall thickening, and adhesion to the surrounding structures, making surgical resection technically challenging. Herein, we report a case of a 33-year-old man with an infected unilocular thymic cyst that was successfully treated with robot-assisted resection following antibiotic therapy. Contrast-enhanced computed tomography showed a 36 × 28 mm cystic lesion in the anterior mediastinum with surrounding inflammation. After improvement in inflammatory markers, surgery was performed using a right thoracic approach with the da Vinci Xi system. Although dense adhesions were observed near the left brachiocephalic vein, successful and precise dissection was achieved without vascular injury. The patient was discharged uneventfully on postoperative day five. Pathological examination confirmed a unilocular thymic cyst lined with columnar and squamous epithelium, with histiocytic infiltration and fibrosis consistent with a chronic infection. This case highlights the successful application of robot-assisted surgery in the management of infected thymic cysts, particularly in anatomically complex or inflamed regions. Early intervention during the subacute phase may facilitate safer resection and help prevent complications such as mediastinitis or recurrence.