The common causes of testicular swelling with a mediastinal mass include lymphoma, leukemia and germ cell tumors. His CBC does not show any signs of leukemia. Beta HCG and Alpha-fetoprotein, both markers for germ cell tumors, are normal. Testicular biopsy demonstrates the presence of a lymphoblastic lymphoma. Bone marrow examination does not show marrow involvement.
Mediastinal masses are the most common thoracic masses in children.
The diagnosis of lymphoma should be made expeditiously, as it can disseminate rapidly. Diagnostic studies should include complete blood count, sedimentation rate, serum LDH, Beta HCG, alpha-fetoprotein and a chest radiograph. Early involvement of an oncologist is essential in order to facilitate an appropriate work-up. Teaching points 1. Any patient with painless testicular swelling not associated with underlying inflammation, trauma or infection should have a chest radiograph to identify the presence of a mediastinal mass or parenchymal lung lesions.