Inflammatory myofibroblastic tumor arising from the ascending aorta mimicking a thymoma.

An inflammatory myofibroblastic tumor originating from the aorta is extremely rare. Here, we report a case involving a 41-year-old female patient with an aortic inflammatory myofibroblastic tumor. Although preoperative imaging showed a mediastinal mass indicative of invasive thymoma, surgical findings revealed that this mass originated from the aorta. The patient underwent partial resection of the aorta, including the mass with patch angioplasty. Based on the postoperative histological findings, the patient was diagnosed with an aortic inflammatory myofibroblastic tumor and is currently under outpatient follow-up.