Chest computed tomography (CT) of a 22-year-old man with a history of long-term low fever and nonproductive cough demonstrated lymphadenopathy in the superior, middle, and posterior mediastinum. Slight bilateral gynecomastia was also observed on the CT scan. Subsequent physical examination and ultrasonography revealed a left testicular mass, and abdominal CT showed retroperitoneal lymphadenopathy. Left orchiectomy was performed, with the histological examination confirming the diagnosis of seminoma.