Mediastinal Nonseminoma

Mediastinal nonseminomas have certain unique aspects. The tumors are more frequent in individuals with Klinefelter syndrome and are associated with a risk of subsequent development of hematologic neoplasia that is not treatment related.[9,10] Approximately 50% of patients with mediastinal nonseminomas will survive with appropriate management.[11] High risk is partially related to tumor bulk, chemotherapy resistance, and a predisposition to develop hematologic neoplasia and other nongerm cell malignancies. In an uncontrolled study, some patients with a postchemotherapy residual mediastinal mass achieved long-term disease-free survival after complete resection, even when serum tumor markers were elevated.[5][Level of evidence C2] Patient selection factors may play a role in these favorable outcomes.