Thymoma is the most common neoplasm of the anterior mediastinum and has malignant potential. Germ cell tumors (GCTs) found in the anterior mediastinum are usually benign, and malignant GCTs, such as seminomas, are rare. Histologically, mediastinal seminoma is indistinguishable from testicular seminoma except for site-associated morphological features such as lymphoid follicular hyperplasia. Therefore, excluding metastasis is very important. Recently, we treated a young adult patient with multiple thymic masses that occurred simultaneously. The patient underwent a thymectomy for the removal of the mediastinal masses, one of which was diagnosed as type B2 invasive thymoma, and two of which were diagnosed as primary mediastinal seminomas with massive follicular hyperplasia. The patient received adjuvant chemotherapy after surgical resection. To our knowledge, this is the first description of a thymoma and a mediastinal seminoma occurring simultaneously in the thymus. We present this case along with a literature review.

Rationale:Ruptured aneurysm originating from the left coronary sinus of Valsalva into the left ventricle (LV) is extremely rare. Imaging features of sinus aneurysm has been commonly reported using echocardiography or angiography. Here, we report multidetector computed tomography (MDCT) findings of left sinus of Valsalva aneurysm extending into the LV and caused severe aortic regurgitation (AR) in a 44-year-old male with latent infective endocarditis. The role of MDCT in preoperative surgical planning was also emphasized.Patient concerns:The patient visited our hospital due to worsening exertional dyspnea for 3 months.Diagnoses:On cardiac computed tomography (CT) using 320-MDCT, a saccular aneurysm arising from the left coronary sinus of Valsalva extending into the LV was diagnosed as the cause of severe AR.Interventions:The patient underwent resection of the aneurysm, aortic root reconstruction, and aortic valve replacement.Outcomes:The patient made an uneventful recovery. Follow-up echocardiography showed no paravalvular leakage with improved LV function.Lessons:MDCT with wide coverage and high temporal resolution can provide exact and comprehensive information about complicated conditions, leading to confident surgical planning and successful management.