BACKGROUND: Primary mediastinal non-seminomatous germ cell tumors (NSGCTs) are aggressive and carry a poor five-year disease free survival rate even with aggressive treatment. We describe a young adult male with primary mediastinal NSGCT presenting with airway obstruction and superior vena cava syndrome (SVCS).

CASE REPORT: The patient presented with four weeks of nonproductive cough, weight loss, and right-sided pleuritic chest pain. Chest computed topography (CT) imaging demonstrated a right-sided mediastinal mass determined as a yolk sac tumor on biopsy. The patient underwent induction chemotherapy with etoposide and cisplatin for stage III NSGCT. In the interim, he developed SVCS warranting a second cycle of chemotherapy along with intravenous steroids, with notable improvement in symptoms. However, serial alpha-fetoprotein (AFP) measurements showed progressively increasing levels up to a maximum of 18,781 ng/mL indicating treatment failure. He is currently on salvage chemotherapy.

CONCLUSIONS: Obstruction of the SVC by external compression is often a manifestation of a malignant process in the thorax. SVCS is a medical emergency and occurs in 6% of patients with mediastinal GCTs. Historically, irradiation was initiated without a histologic diagnosis to relieve the life-threatening obstruction. However, newer data suggest that it is acceptable to defer therapy until a full diagnostic workup is completed. This case highlights the malignant nature of primary mediastinal NSGCTs. In addition, inasmuch as SVCS is dramatic in presentation, it is important to recognize that symptomatic obstruction often develops over weeks or longer. In a hemodynamically stable patient, an accurate histologic diagnosis prior to starting treatment is essential in guiding therapy.

Keywords: Endodermal Sinus Tumor, Mediastinal Neoplasms, Neoplasms, Germ Cell and Embryonal, Superior Vena Cava Syndrome, Yolk Sac