Surgical resection of a giant polycystic seminoma of the mediastinum

Mediastinal germ cell tumors consist of only 10–15% of all mediastinal tumors, while mediastinal seminomas account for approximately 25–40% of all primary malignant mediastinal germ cell tumors (1,2). These are slow-growing tumors that typically manifest as a solid, lobulated mass on a computed tomography (CT) scan (3); no specific serum tumor markers exist on mediastinal seminomas. Here, we describe a patient with a giant polycystic seminoma that was diagnosed on pathologic examination after surgical resection.