Thymoma is a relatively common tumor type with unique clinicopathological characteristics among < positive > anterior mediastinal tumors. As a kind of thymic epithelial tumor, B3 thymoma has certain invasiveness, which can cause invasion to important surrounding tissues and organs, resulting in complex disease and increased treatment difficulty [1-2]. When the tumor invades the right upper lung, ascending aorta, superior vena cava and other key structures, not only the difficulty of surgical resection is greatly increased, but also the risk of bleeding is significantly increased. At the same time, it has a serious impact on the patients' cardiopulmonary function and general condition, which brings great challenges to clinical diagnosis and treatment [3].